Can a decision be both + and - EV?

Question: Is there ever a situation that in a short-term a certain decision might be + or - EV but in the long-term the EV actually change?
Answer: My interpretation is that mathematically, the expectation in EV is taken across the probability distribution of poker cards that are yet to be dealt in a particular hand as well as the randomness in opponents' play, and it is assumed that every other piece of information (including situation, position, etc) you can have is already taken into account when you calculate your EV in a hand. Under this definition, there is only one EV for each decision you make, as Lee says.
More generally, what you should really care about is not only your EV for one particular hand, but the EV of your future decisions. e.g. Calling the river with a moderate hand against a hyper-aggressive player will discourage bluffs in the future, and may be +EV even if you lose the pot. This is called investing in a reputation. Conversely, occasionally bluffing may also affect your future hands' EV positively if it reduces the image that you're tight and balances out your real hands. If you include these considerations in your EV calculation, then you might well make a distinction between "short EV" and "long EV", but this reduces the clarity and thus helpfulness of the term. I prefer to use "EV" simply to judge correct play in a hand (taking into consideration the table history and current situation, but not the future), and use additional terms to describe other considerations, like being in a bubble or when you're building an image.
Answer: In this case "short term" implies that you may have specific situational context that might be relevant to this narrow class of decisions. Say you're in a NLHE game and you have aces pre-flop and you know that you're sitting immediately to the right of a a big-stacked aggressive opponent who will very often punish your limp with a big raise. Since he's been drinking a lot, he's less likely to interpret your limp as a trap, so you might be more likely to limp here so you can reraise him when it comes back to you. In this case, the +EV play might be to limp, given your situational awareness of your relative position, his tendencies, and his lack of sobriety that you're extremely likely to get him to risk his stack. In the bigger picture, though, with more player types and more possible scenarios, pre-flop limping with aces is usually a bad idea. So, I'd say that this is one place where a certain "decision" -- limping aces pre-flop in holdem -- might be -EV in some cases but +EV in others.
Another example might be in a tournament where there are 10 players remaining and the last 9 players get equal prize money, while the 10th gets nothing. You're the short stack and have aces pre-flop. There is action ahead of you among the smaller stacks. What's the right move?  Of course you need to fold here. In this case, folding aces pre-flop is the +EV decision.
Of course, you could also certainly argue that these examples are really distinct types of decision because the context is different in each.
Answer: No, the EV is the EV. But probability is a function of knowledge. Your estimate of the likelihood of the various events that go into your calculation of EV will change over time with new information, so that what may seem like the "same situation" to you at different times might actually be a very different situation when you take into account your added knowledge.
Answer: EV is pure math and is based on cards. Although there are cases as @Chris Farmer said where the EV may be positive but even the slight chance that you have to lose should ignore the EV. Such case are the satellite tournaments where a number of players get exact prize and another number of players get exact nothing.
In such cases a 80+% winning chance (or say a sky high EV or easier, aces) doesn't mean much if there are, say, tiny stacks out there to take the risk as they're closer to elimination than you. EV situations are good when you actually win something in return than nothing.
If, for example, a big stack got all-in and you have aces and a similar stack (big) and call, while there are tiny stacks out there and 1 place before actually win something, then you're doing it wrong. In such cases, big stacks should only play the tiny stacks and ignore the EV of their cards and the other big stacks as well.
Another example is single table tournaments or STT as @Chris said. You have 10 players, 3 are getting a prize. The catch here is that the prizes have not so big of a difference as MTT top places but like 20% to 3rd, 30% to second and 50% to first (or something like that). The 4th player does get a honorary nothing while the 3rd player gets quite big prize. In such case, where the prize of 3rd player doesn't really have a colossal difference from 2nd and the 1st prize is really a double prize, your EV situation as well change. You now have to play mostly AA, KK and the likes, regardless the fact you are huge favorite in most hands, although one step from the honorary 4th position and the nothing prize. All this provided if there is at least one smaller stack out there and not you.
Answer: EV is a mathematical term that only makes sense on the long run.
In probability theory, the expected value of a random variable is intuitively the long-run average value of repetitions of the experiment it represents
Thus there's just one value of EV which more or less translate to "the expected total value if we were to repeat this draw an infinite (or in practice very big) number of times.
Statistically a sample size of one hand means nothing (you can't extract a value from one coin flip), as you increase the sample size you can draw more conclusions. With a big enough sample size you can express statistical truths with a given confidence interval.
That level of confidence is important. When we talk about EV in poker we simplify part of the information to be able to use math to make a decision. Thus, you can compare the odds of getting there against the pot size and calculate what we normally call EV.
In reality, even though we don't say it, what your are calculating is "if I was to repeat this exact same situation 10000 times with this cards and this flops I'm 98% confident I would make around 100$"
This is just a simpification as, obviously you're not going to be on the same exact situation that many times but the simplification lousy translate to "if I play this kind of situation (I.e. Flush draw) all in every time, in the long run given enough times I'd expect to gain this much value" that is the EV, is always in the long run.
Answer: Going by probabilities where the expected value is the average of the sums of all possible outcomes in the set, the standard application of EV in poker is for hand analysis, meaning did I make the right decision based on the current pot, cards, and previous play.  In this sense we are dealing with constant values and your best estimation of the opponent and the EV is exactly one value which you can only guess based on your evaluation of the possible range of hands your opponent might have.
In reality, the future is variable, so when we look at the possibility of repeating this exact situation against the exact same opponent, the next time will likely not have the same set of outcomes for the sample set of possible plays, which means your EV will likely be different next time.  In this case it seems reasonable that maximizing your EV this time might make your play more obvious if you use the same reasoning, and hurt your long turn profits.  This is one of the reasons that Mason Malmuth and David Sklansky make a distinction between "perfect poker" and "excellent poker."  To truly maximize your EV, both situations might have to be played differently, and you're definitely going to have to think about more than just the combinatorics.
Think about the information you give someone when you make a bet sizing decision.  Maybe a tiny sucker bet on the river will get you a call when you lose only a little now, but might induce a bluff raise where you can gain alot next time.  There is a specific case where you can go -EV immediately to go +EV in the long run.
Answer: Note that EV is usually not a precise value, but an estimate.  Because it is an estimate, the true expected value of an action can span a range which includes both positive and negative values.  For example, calling might have an estimated EV of 0.05 bets, but the standard deviation for that estimate might be 0.15 bets, leading to a 95% confidence interval of [-0.10, 0.20] bets.
See also: http://en.wikipedia.org/wiki/Standard_error#Standard_error_of_the_mean
Comment: I disagree. Expectation is, by definition, a weighted average. The realized value might have a range and variance, but there is only one EV ex-ante (conditional on your information and beliefs). http://en.wikipedia.org/wiki/Expected_value
Comment: You are confusing the standard deviation of the outcome with the standard deviation of the EV estimate.  Any construction of EV (in poker) can only be an estimate.  As such, that estimate has an associated standard error (the standard deviation of the estimate).
Comment: Your point is technically true; for every estimate, we can always incorporate uncertainty about that estimate, up to infinite order. So if you want to estimate the "population" mean of EV, there is indeed variance from not having enough information about a player. However, I fail to see how this additional qualification is in any way useful to your decision-making, since you'll still play the action that has the best EV estimate with as little estimated variance in the action as possible, while variance in the mean *estimate* doesn't affect your choice at all, unlike actual variance.
Comment: Of course it will affect your decision making process.  For example, you have two choices, with EV intervals of [0.1,0.2] and [-100,101].  The EV estimate of the second is higher than the first, but you might choose to take the more certain action over the higher EV action.
Comment: Again, you're conflating estimated variance [of an action] vs variance in the mean estimate. Expected value is useful, variance in useful, variance in estimated EV isn't.
Comment: While it may not be useful to you, it is most certainly a useful thing: http://en.wikipedia.org/wiki/Standard_error#Standard_error_of_the_mean
Comment: Only in scientific settings when we are inferring population characteristics. Not in decision-making. You seem to have been misled by how we teach undergraduate statistics courses.
Comment: As it turns out, you can use statistics to estimate expected value.

Can a decision be both + and - EV?


How do I replace a 'serverName' parameter in a log. xml file

Question: How do I replace a 'serverName' parameter in a log. xml file of a .war application with the Ibm websphere server name on deployment time (by command ile on linux env).
I mean what is the syntax for it in the log.xml file and in the command line.
Can I do this also with the wasadmin app ?
Answer: As far as I am aware, you don't - depending on which commons-logging method you're using it's different, but in general the external Log4j/JSR configs only dictate the logging levels, patterns and filenames (as well as the base factory used, etc.). You need to actually edit your Java code to pull that out (getProperty) and insert it into the log.INFO() (sic) calls when writing. To my knowledge there's no way to do it at the configuration (XML) level.
Comment: In my  log.xml file I point to the log file (full path). The directory name where the file locate should be the server name . I need it as a parameter


How can I move my PSP game saves onto my PS Vita?

Question: I have an old PSP and a PS3 and PC. I have a bunch of PSP game saves for PSN games (patapon ect) that I would like to move over to my Vita because they work on the Vita.
How can I move my PSP's save files onto my Vita?
Comment: I found [this possible solution](http://www.gameblurb.net/more/editorials/how-to-transfer-psp-save-files-to-vita-pc-instructions/) but I'm redownloading my PSP games so I can try it out.
Answer: Copying your PSP save data
Plug your PSP into your PC with a Mini USB cable (the kind that fits into the top of your PSP) and select the USB Connection option in the PSP System menu.
The PSP should show up as a connected drive in your My Computer menu. It's probably called "Removable Disk" if you're on Windows. Open that drive and navigate to the PSP folder.
Copy the SAVEDATA folder onto your PC somewhere like you Desktop. That folder has all your PSP saves and we'll copy them to the PS Vita soon. If you're concerned about how much space the data will take up on your PS Vita, check how large this SAVEDATA folder is, you're about to copy that much data onto your Vita. If it's too large, we can only copy the specific games you want the data for later.
Prepare your PS Vita to copy the files
Download any one PSP game onto your Vita and play it enough to generate a save file. Any game will do, it doesn't have to be a game you want to copy the save data for.
Install the PS Vita Content Manager Assistant for Windows or Mac OSX.
Connect your Vita to your PC with the USB cable and open up the content manager. Pick Copy Content: PS Vita System -> PC -> Applications -> Save Data (PSP/Other).
You should see the game you played earlier in a list; tap the PSP game to select it and hit copy. Click Okay to copy it onto your PC.
Find the folder on your PC the Vita copied to; it should be in your Documents folder in a folder named PS Vita, in that folder there's a folder called PSAVEDATA. In that should be a single folder named with random letters and numbers. Open that folder; this is where we're going to copy the PSP Save Data.
Copy the files onto your Vita
Open up the SAVEDATA folder from earlier, those are your PSP saves. Also open the PS Vita  folder we mentioned before that has your PS Vita's copy of the save files (you want to be inside the folder with the name that's random letters/numbers). Copy and past ALL folders from the SAVEDATA folder into the folder named with random letters. Say Yes to any dialogs that ask if you want to merge/copy files; this means you're overwriting the Vita's copy of the save file with the PSP one.
Now just open Content Manager on the Vita again and pick Copy Content: PC -> PS Vita System. Pick Applications -> Saved Data again. You should now see all of your PSP save data. I recommend hitting Select All and just copying all of this data over. You can also pick and choose just the games' data you want to copy over if you want to save yourself some space.
Pick Copy and hit Okay again, it will ask you if you want to overwrite any data you have on the PS Vita for the PSP games; you want to do this, so click Apply to All and tap Overwrite.
Your PS Vita now has all save data from your PSP and you can keep it there forever, and it's also stored with your PS Vita backup. Any time you download a PSP game onto that Vita, it will start with the save data you copied from your old PSP, no need to repeat this for each game!
Comment: "Your PS Vita now has all save data from your PSP" - except for the device-locked save files, as far as I know.
Comment: will the games still remain in the psp?
Comment: @Moiz yes, it's just copying data, not removing it. Plus you can just redownload the games to the PSP later anyway, activating games on PS Vita doesn't remove your ability to play them on a PSP (you get to activate on 2 of each console, IIRC)
Answer: Here how I did it with my Final Fantasy Tactics (FFT) save files:
I can't guarantee it'll work for you.
Your PSP save games are accessible in the memory stick you used to save your files. Find a way to read the memory stick in a PC with a memory card reader (I don't know if you can backup your files from your PSP direclty to a computer...). The memory stick will have a folder structure like (GAMES, SAVEDATA, etc.) In the SAVEDATA directory you'll find a bunch of subfolders for each of your games that had a saved data on this memory stick. Locate the folder/s you want to import into your PSVita (for me it was a folder named ULUS10297FFT0000).
Download the PSP games you want to play to your PSVita system. Optionally, to facilitate the transfert, play your game until it create a save game. Then plug your PSVita to your PC and install the Content Manager. Once installed you will be able to save games and files to your PC. Open the Content Manager App inside your PSVita system and select the "PS Vita System to PC" option, then "Applications", then "Saved Data (PSP(tm)/Other)". Check all the game you want to import the save game for and press "Copy". This will copy the data to your PC.
Go to the locations of the save files in your PC. (by default it should be inside your "My Documents" folder in a folder named "PS Vita") There'll be a folder named PSAVEDATA. Inside of it there'll be another folder with a random name that is, I think, a reference for your PS Vita system (In case you have multiple systems saved to the same PC). Open it and you'll find a list of folders with names that looks just like the folder in your PSP memory stick SAVEDATA folder. Copy the whole game save folders (ULUS10297FFT0000 for my FFT) into the your PS Vita save game folder ("My Documents/PS Vita/PSAVEDATA//") to replace the folders your games created.
Now return to your Content Manager app in your PS Vita. If your are still at the previous copy screen then press "Cancel" and the back arrow until you can choose "PC to PS Vita System" option, then "Applications", "Saved Data...". Check the save game you want to import, press "Copy" and it should be done. You can now go verify into each of your game to make sure your save games have been imported correctly.
Answer: One other thing to note. First, if you find the Content Manager icon in the system tray (by the Clock on the task bar), you can right-click on that and pick Settings.  On the settings screen toward the bottom there is a hot-link that takes you directly to the folder where you should copy your save files.  There are even directions on screen telling you how to move your PSP save files.
I was able to move PSOne classic saves such as FFVII, FFIX as well as PSP saves (Lemmings) and PSP minis (Tetris) by following the on-screen directions.  Before trading my PSP Go in to Best Buy, I copied all of my saves files to a NAS drive from my Mac.  Then I copied them from the NAS to the PC where I have content manager installed today. Point being, if you have the files saved somewhere, even if you no longer have a PSP this will still work.
Answer: Plug your PSP into your PS3 with a USB cable and select the USB Connection option in the PSP System menu. Copy the PSP games into your PS3, then unplug your PSP and plug your PS Vita to your PS3 and it will automatically copy the PSP games into your PS Vita.
Answer: Plug your PSP into your PS3 with a USB cable and select the USB Connection option in the PSP System menu. Copy the PSP games into your PS3, then unplug your PSP and plug your PS Vita to your PS3 and it will automatically copy the PSP games into your PS Vita


Unable to RDP into a Hyper-V VM

Question: For several months now I have been using Hyper-V (2008 R2) to host a Win 7 VM. For most of that time I was able to RDP into it, recently I have not been able to. I am not aware of having changed anything, but it has stopped working.
Any suggestions?
Answer: Is the VM's NIC still 'ping'able (if you allow that of course)? if that works then try telnet'ing to that box's port 3389? if that works then it's an OS issue, if not then you probably have switching/routing/firewall issues.
Answer: You need to know where in the stack you're looking for problems. If you're sure that all of the basic network settings are correct and verified that other network connectivity is working, check the firewall settings first, then run a WireShark dump on port 3389 as you make connections to the box to make sure that RDP traffic is actually making it over to the machine. Once you've verified that, you can start looking into issues in Remote Desktop Services (make sure Remote Desktop access is still enabled!).

Unable to RDP into a Hyper-V VM


Why Limit of $0/x$ is $0$, if $x$ approaches $0$?

Question: It might be a silly question, but to me it is not obvious why the following expression holds:
$$
\lim\limits_{x\rightarrow 0}\frac{0}{x}=0 ?
$$
Answer: A limit $L$ of a function $f(x)$ evaluated at a point $x = a$ is not necessarily the value $f(a)$ itself.  It is a value for which $f(x)$ approaches $L$ "as close as we like" if we make $x$ "sufficiently close" but not equal to $a$.  The subtlety is in how we mathematically formalize the language in quotation marks, which is how we arrived at the Cauchy definition of limit:

We say that $\displaystyle \lim_{x \to a} f(x) = L$ if, for any $\epsilon > 0$, there exists a $\delta > 0$ such that $|f(x) - L| < \epsilon$ whenever $0 < |x - a| < \delta$.

Of course, we do not need to appeal to such a definition in this case because as others have pointed out, $f(x) = 0/x = 0$ whenever $x \ne 0$; hence $$\lim_{x \to 0} \frac{0}{x} = \lim_{x \to 0} 0 = 0$$ directly, because again, the limit is evaluated by considering the behavior of $f(x)$ in a neighborhood of $a = 0$, not the value of $f(0)$.
Answer: $$\frac0{1}=0$$
$$\frac0{0.1}=0$$
$$\frac0{0.01}=0$$
$$\frac0{0.001}=0$$
$$\frac0{0.0001}=0$$
$$\frac0{0.00001}=0$$
$$\frac0{0.000001}=0$$
$$...$$
Answer: It's simple:
The limit is the value that the function approaches at that point, simply put, it depends on the neighboring values the function takes.
Take  a graph of the function $f(x)=\frac{0}{x}$:

You see that from any possible angle, the only value the function approaches when $x\rightarrow0$ (or wherever in the known universe) is $0$.
A different scenario would appear with, for example, $f(x)=\frac{sin(x)}{x}$. Here, you can see in the plot that the line approaches $1$ as it gets close to $x=0$, that's why this limit is equal to 1.

And in both cases, $f(0) = \frac{0}{0}$. The function is, in both cases, undefined at that value of $x$, but the limit tells you toward which value it approaches.
Answer: You've received great answers thus far, so there's no need to repeat what's already been stated, and stated well.
I'll simply add this, for a different take, given that you've already encountered integrals and double integrals, I take it you've encountered L'Hospital for limits:
Even if you to try to evaluate at the limit at $x = 0,$ we get the indeterminate form $\dfrac 00$. By L'Hospital's rule, then, $$\lim_{x\to 0} \frac 0x = \lim_{x \to 0}\frac{(0)'}{(x)'} = \lim_{x\to 0} \frac 01 = 0.$$
Answer: This is true simply because as you take $x \to 0$ (for $x\ne 0$), we have $0/x=0$. (Think about the convergence of the sequence $0,0,0,0,\ldots$.) When you take the limit, you don't care about what happens when $x=0$; you only care about what happens around it.


The Landscaping tag with Gardening and Landscaping needs much BROADER knowledge bases

Question: Landscaping is a HUGE title.  Garden walls for example are perfectly within our scope.  Grading, drainage, soils, climate, weather, chemistry, siting buildings are all so very much part of landscaping.  This should probably be a site unto itself.  Possibly with more than asking simple questions.  Plants or 'soft scapes' are but a SMALL part of landscaping.  This title has got to change or we need more landscape PROFESSIONALS involved.  Period.
Comment: What are some suggestions for a better title?
Comment: Landscaping needs a separate site.  This will probably cross over with DIY, homeimprovement and design as well as gardening.  Exterior home design...maybe a better title for a new site would be Landscape Design or Integration of Home and Garden?  To encompass soil, weather, zones, architecture, hardscapes for sure, hiring contractors/subcontractors, irrigation, lighting (out of doors), grading/drainage, how to select plant material, how to lay out for planting, how to plant B&B, bareroot and different sized plants, how much is too much or where devaluation of landscaping occurs, MULCH...
Answer: It's like going upriver when you try and move away from the SO question and answer format.  The focus for all SO sites is questions that are focused and have one correct answer.
That is not an easy fit.  See this question here which has been closed as too broad.  This would be a great exam question for a landscape design course. You could get a different answer from every student and they could all be right.
Landscape design does have a technical basis.  Hardscaping in particular has a limited range of techniques to build something that will not fall down.  This type of question fits.  Design is more of an art and subject to interpretation. That's why we read about gardens designed by individuals or done in a particular style.  The range of correct answers to many landscape design questions is large and not a good fit for a web site.
Comment: Yes and no...good landscape design is low maintenance and follows rules all artists use.  Truly NOT subjective.  Beauty is really not in the eye of the beholder.  To make beautiful things they need to fullfill certain rules such as limiting stimulation, being functional, abiding by environmental and legal rules and my favorite 'test' is LOW maintenance.  Non-artists and laymen won't know WHY a design is great but normal humans will always sense the 'beauty'.  Landscape Architects aren't 'artists' more akin to 'problem solvers'....then there are the weird humans who think astro-turf as beesknee
Comment: I realize this is a tough...problem.  I don't know how I would change things at the moment.  I am working on a second design via this site and the internet.  Soon, you'll be able to see results from the first design 'help'...getting ready to actually install this next month.  Perhaps that will highlight ways to make changes, fewer the better.  Scoring and grading landscape design has shown me that there are different graphics, ideas but a good design is more universal than you think.  Each project however is totally unique as are the clients and environments.
Comment: I would not call Versailles or the gardens of the Italian nobility to be low maintenance but they are called good design and written about in every garden history book.  Would you call the Gardens of Bomarzo https://en.wikipedia.org/wiki/Gardens_of_Bomarzo that look better with a few centuries of neglect to "follow the rules"?
Comment: Grin...one of the parameters of design IS 'how much maintenance can you afford'?  That is always factored in...lots of clients have personal full-time gardeners.  Changes the design a bit...but I don't get those kinds of clients that often.  To allow a garden to go neglected truly proves whether or not it was a great design...I think it DOES get subjective when people don't care about money necessary for maintenance.  Those Italian gardens to me AREN'T great design.  I wouldn't do that to anyone!  Maybe a taste of hedge plants and they are satisfied/humbled.
Comment: Gotta understand the mentality of these...nobility.  Very into CONTROL.  Man OVER nature not Man WITH nature.  We understand a heck of a lot more than they ever did.  Hopefully we've evolved!!  Grins!!


What is a good mathematical description of the Non-renormalizability of gravity?

Question: By now everybody knows that gravity is non-renormalizable, what is often lacking is a simplified mathematical description of what that means.  Can anybody provide such a description?
Comment: The CGHS model in 1+1D is renormalizable.
Comment: Now I understand the interest in extreme black holes a little better http://media.physics.harvard.edu/video/index.php?id=COLLOQ_STROMINGER_091310.flv&width=640&height=360
Comment: Related: http://physics.stackexchange.com/q/61243/2451
Answer: How about a description in words instead? I think the mathematics is not the point so much. Other answers lay out the mechanics in detail. The short answer is that the theory has infinitely many divergences which cannot be absorbed by fixing finitely many couplings to their observed values. This means it is not predictive, or in more fancy words does not provide algorithmic compression: the amount of input it requires equals the amount of output it produces.
But the talk about divergences masks the physics of the situation, which I'll try to describe:
Any theory has couplings which describe the possible interactions of the system. When you probe the system at different length scales, or energy scales, those couplings change in a calculable way. This is the process of renormalization, which fundamentally has nothing to do with infinities.
Renormalizable theory is one that can be continued to high energies, or short distances, without encountering any difficulties. This means all couplings remain small, and all calculations are reliable. In non-renormalizable theories, the higher energies you probe the system, the stronger the couplings become, at some stage they become infinite. This means that you cannot do reliable calculations, which is normally an indication that there are some physical effects that you are missing. There are many examples where such physical effects are well-understood, for example new degrees of freedom (which are not visible at low energies) become important at those energy scales.
In gravity, when you calculate in perturbation theory, for small perturbations around flat space, it looks like the coupling becomes strong and something is missing. The mechanics of seeing this is straightforward and not that illuminating. Perhaps one intuitive way to understand this is that in gravity the interaction coupling is governed by the energy, so almost by definition it grows with energy...Most likely scenario is that we need new degrees of freedom to complete the theory at short distances. One suggestion for "UV completion" is string theory.
There is another scenario which may apply to gravity. Once the couplings become strong, you cannot any more reliably calculate anything, and that includes their scale dependence. So it is a logical possibility that they will stabilize at some finite value, and don't go all the way to infinity. This scenario is called asymptotic safety. In my mind this is very unlikely, and there is no indication* this scenario applies to gravity, but it remains a logical possibility.
(*I know about the various claims, this is a statement of my personal opinion.)
Comment: For future readers, be sure to look at answers provided by space_cadet and Lawrence B Crowell, I would say that its the totality of the three that answer the question.
Answer: One of the simplest ways I know of to see the non-renormalizability of gravity is to note that the coupling constant in this case (Newton's constant $G$) is dimension-full with dimensions of $L^2$.
The action for GR is of the form:
$$ S_{EH} = \frac{1}{8\pi G} \int d^4 x \sqrt{-g} R $$
When we try to expand this action as a power series in $1/G$ we see that each additional term has an extra power of $1/L^2 \sim k^2$, rendering the integration over momenta divergent in each term.
This is in contrast to QED where the coupling constant is the fine structure constant $\alpha = e^2/\hbar c \sim 1/137$ which is a dimensionless number.
Edit: For a more comprehensive and informed account see @Lawrence's answer below.
Answer: The number of divergences is not finite.  In QED and other YM theories the divergences are finite and may be absorbed into the renormalization of mass or gauge charge.  The rules for anomaly cancellations may be established in a finite description as well.
With quantum gravity in a QFT setting has a quadratic momentum dependence on the graviton vertex $V[k]~\sim~k^2$.  This is due to the form the action takes in an expansion of the metric density ${\tilde g}_{\mu\nu}~=~g^{1/2}g_{\mu\nu}$ with
$$
{\tilde g}_{\mu\nu}~=~\eta_{\mu\nu}~+~\kappa^2{\phi^\alpha}_\mu\phi_{\alpha\nu}.
$$
The action $L~\sim~\kappa^{-2}\phi^{\alpha\mu;\alpha}{\phi_{\alpha\mu}}^{;\alpha}$ gives a three point vertex function which is quadratic in the momentum.
A general Feynman diagram will also have internal lines $I[k]~\sim~1/k^2$ and loops with $L[k]~\sim~\int^kd^4p$.  So the internal portion of a Feynman diagram will have internal lines, vertices and loops.  The Euler characteristic for a graph
$$
1~=~V[k]~-~I[k]~+~L[k]
$$
is used in conjunction with the degree of divergence of these parts of the graph $D_V~=~2$ $D_I~=~-2$ $D_L~=~4$ with a total divergence $D~=~4L[k]~-~2I[k]~+~2V[k]$, so that
$$
D~=~2(L[k]~+~1).
$$
Consequently the divergence has an unbounded growth with the order of each Feynman diagram.
As pointed out above the gravitational constant has units of $[G]~=~Area$, which differs from the fine structure constant $\alpha~=~e^2/\hbar c$  and other gauge couplings which are unitless.  The dimensional content of the gravitational constant is related to the problem of quadratic vertices.  The interest in holography and AdS/CFT correspondence is with how gravity in an AdS space with negative Gaussian curvature may be replaced by quantum field on the boundary.  So the divergence in a naïve QFT theory of gravity may be substituted with a stringy theory on the boundary of a space where these divergences do not exist.
Comment: i have a question.. whenever you say that the nunmber of divergence are not 'finite' you say that there are many divergent integrals of the form $ \int d^{4}k. k^{n} $ with n=0,1,2,3,... and so on. when you say that the number of divergences is 'finite' you are referring to the fact that you have only 2 or 3 different types of divergent integrals i am right ??
Comment: Can you explain why G has units of area $m^2$. A quick search reveals that the units of G are $6.674×10^{−11} m^3 kg^{−1} s^{−2}$. Is G here not the gravitational constant?
Answer: The simplified way to understand gravity's non-renormalizability is to realize that one needs to make an infinite number of infinite scaling which is not possible. In general, if the number of counterterms in the Lagrangian, required to cancel the divergences is infinite then the process of renormalization fails.
Answer: Often infinite perturbative corrections are a sign of a "bad start" in the perturbation theory (providing the exact equations are correct). In Physics one often starts from incorrect equations too and "repairs" the wrong solutions "on go", for example, by discarding infinite corrections to the fundamental constants. It "works" only in case of very simple "perturbation" Hamiltonians. In GR it is not the case (as in many other non-renormalizable QFT).


Easy way to earn money on Pokemon Omega Ruby/Alpha Sapphire?

Question: I've recently been attempting to complete the Hoenn pokedex. I need a lot of pokéballs and ultra balls to catch em' all. If anyone knows an easy way to do this please simply explain it. I believe that repeatedly challenging the Elite Four may work, but I don't really want to do that.
Comment: Though this doesn't increase money, what you could do is save before trying to capture a particular pokemon, then try to capture it. If you fail, simply choose a previous save and try again. This doesn't help if you spam many ultrballs just to try to capture one pokemon.
Comment: Go to the Elite 4 with a Pokemon holding a Amulet coin. Then you would have an increased amount of money earned.
Comment: The fastest way I know of to make money is to battle. The Elite 4 should award you with quite a pretty sum of money. If it's just Ultra Balls you need to buy, then money shouldn't be much trouble, even without beating the Elite 4. I've just beaten the Team Aqua base and have over 50 Ultra Balls in my inventory and enough money to buy 50 more of them.
Answer: You should give Amulet Coin or Luck Incense to your lead Pokemon.
O-Powers can help you, too. Prize Money Power that raises the money gained from a trainer battle, and Bargain Power that decreases the amount of money you have to spend on items.
Comment: If you prefer, the Luck Incense has the same effect.
Comment: @pinckerman I've just started the game and came across this beauty of an item :) spent all my money buying it but boy does it build back up! definite investment!
Comment: As Bulbapedia, you receive it from mom after obtaining 5th Badge.
Comment: I don't know where to find the Amulet coin. Yes I have the O-powers but the *Amulet Coin* sounds more interesting
Comment: @SaturnsEye I'm glad it was useful :)
Answer: Earning Money:
You can use these to earn more money:

Amulet Coin* or Luck Incense** (Make your lead Pokemon hold them, they do not stack)
Prize Money O-Power***

You can make the best use of them by re-challenging:

Trainers (Check the AreaNav's 'People' function to find them)
The Elite Four (also unlocks other goodies)
The Food Court in Mauville City.
Secret Base Trainers (AreaNav 'Bases')

Saving Money:
Having more money is all well and good, but what about spending less as well?

Use Bargain O-Power for discounts (half-price at level 3)
Buy Balls in groups of 10 each, to get the bonus Premier Ball as well.
Pickup Pokemon will occasionally find a Great or Ultra Ball, depending on their level.

Catching Pokemon
Now, onto the crux of the issue, catching Pokemon efficiently, so as to waste less Pokeballs:

Use a Catcher Pokemon. Sleep + False Swipe will make a lot of Pokemon easy to catch, even with regular Pokeballs.
Use Catching O-Power.
Make use of Quick Balls and Timer Balls****.

Quick Balls have a greatly boosted catch rate if thrown as the first move. Good for Pokemon that tend to flee.
Timer Balls have a greatly boosted catch rate if the battle has gone for 10 turns or longer. Good for Pokemon that don't want to stay in their Pokeball/Stay asleep

* You get Amulet Coin from your Mum after the 5th Gym Badge.
** You can purchase Luck Incense in Slateport City
*** O-Powers are unlocked through the 'Strange Men' in Mauville Pokemon Center. Keep interacting with them, exiting and returning to the Center as they leave.
**** Quick and Timer Balls can be purchased from Fallabor and Rustboro Marts respectively.
Comment: the formula for timer balls [was changed in gen V](http://gaming.stackexchange.com/questions/269640/what-is-the-correct-formula-for-timer-balls) so they're better than ultra balls from turn 4, and cheaper!
Answer: The best method is:

Get a Level 100 Pokemon, (Preferably one with a ton of attack, I usually use Dragonite)
Get an amulet coin
Give Dragonite the Amulet Coin
Max out the prize money O-Power
Go to the elites with your Dragonite holding the amulet coin and before each battle use the maximum Prize Money O-Power, After each battle you will get a ton of money.
Answer: I normally go the the E4 for money, with an amulet coin, but I recently found out about the move Payday. All you need is a level 30 Mewoth and teach it payday. Every time you use payday you get 10x the level of the pokemon using payday. For example: If  a level 30 mewoth uses payday once you will get 300 Pokedollars. And Every time you use Payday in one battle it will add up. So if a level 30 Mewoth uses payday 10 times in one battle, you would get 3000 poke dollars. Hope I helped!
Answer: Use Level 1 Prize Money O-Power with Amulet Coin or Luck Incense fighting the E4 and Champion--as long as your Pokémon are strong enough, you can do it multiple times (~48600 Poke).
Also, utilize people with all-Chansey secret bases. Chansey gives more prize money, and if you couple it with the above strategy, it should up your return.
Answer: I suggest looking for the same trainers that battle repeatedly. I used the Bargain O-Power to get myself some good bargains, and I suggest you do so unless you don't have the O-Power.
Answer: Battling the rich boys over and over usually helps. Although if you battle them too many times, they start to get tough. The elite four are BIG money earners, so take every chance you get to beat them. Luck incense and amulet coins always work, especially at the pokemon league. Mauville food court is a place I recommend, you meet lots of trainers there and they always earn you lots. Good luck!
Answer: Get a strong, maybe level 100 Pokémon. Give it the amulet coin and go to route 104, where there is both the lass and the rich boy. Activate prize money O-Power before each battle, and you can speed through the battle. I prefer my Aegislash using Sacred Sword, but any quick animation, powerful fighting type move works fine. At level one prize money, I could get 3 battles in. You do have to wait a bit for both the trainers to be ready and for the O-Power to charge. I got 17,640 per battle, and there's only 2 Pokémon per battle, so I guess it would be around 100k in under 10min, but like 5 min after that for the trainers to get ready, and a few more for the O-Power to charge.


Are Gamma Ray Bursts of galactic or extragalactic origin?

Question: I read about the 1995 Lamb-Paczynski debate on whether GRBs are galactic or extragalactic in origin.  With our current experimental evidence, have we found whether GRBs are galactic or extragalactic?
Answer: Based on our understanding of what might be possible causes for GRB, there's nothing to suggest that this phenomena is isolated to other galaxies alone, but we have so far only detected GRB originating from outside of the Milky Way. Good that we did too, because if any of them happened in our cosmic neighborhood and was pointing towards us, it would be the last thing we'd ever see and would effectively sterilize our planet. More information is available on Wikipedia on Gamma-ray burst, it's actually a pretty good article presenting extensive information on GRB (I guess that's why it's featured there).
Answer: Shortly after their discovery, astronomers realized there were at least two classes of GRB: short events (<2 seconds) and long events (>2 seconds). The long GRB are widely believed to by hypernova, the explosions of massive black holes in very distant galaxies. In fact, they are much further away than even Paczynski and his followers believed at the time of the debate. Consensus on short GRB has yet to be reached, though the neutron star-neutron star merger theory, no longer applicable to long GRB, is still in play for the short ones. Also, some small percentage of short GRB are certainly magnetar flares (such as the famous March 7, 1979 event) but in other nearby galaxies.


Why is my child so scared?

Question: My 5 year old will not go into a room alone by herself... She won't go to the bathroom alone or even play in the next room alone... She freaks out if you leave the room.... It's so bad she will follow me in the bathroom... Has to sleep in my room... Will scream n cry she is scared if I ask her to go do something in the other room... She will make her younger sister go with her.. Recently she has taken up bed wetting because she is so scared to leave the room and go alone to the bathroom... Even if I leave lights on... Whats going on? What could be the problem?
Comment: What types of TV or movies or Youtube type videos does your child have access to? It is possible that your child has seen a scene from a movie/tv show that is super scary, or even an advertisement on the beginning of a youtube video. That happend to my kiddos. There is some scary stuff that pops up for no reason.
Comment: Have you asked her what scares her about the room, and did she give any answer beyond "I don't know"?
Comment: Are there any factors in her life that are causing this and that you feel comfortable to talk about? Your child definitely sounds stressed. Can you do anything to alleviate those factors?
Comment: Did this start suddenly, or gradually, or was it always there and built up recently?
Comment: Possibly you have a mouse or a rat and your child is afraid of encountering it alone.
Comment: My 6 year old son is doing this too. He doesn't scream or cry, but he won't be anywhere in the house alone. He hasn't had any kind of traumatic experience or other kind of "stress" that would trigger this behavior. It gradually worsened from a fear of the dark (normal) to being afraid to go upstairs/downstairs alone, to not even wanting to be in his own room getting dressed while I am in the next room dressing his brother. It's really frustrating. I can't wait for some insight from others who have gotten their kid(s) over this.
Comment: +1 @Jeff.Clark. I had this happen (more mildly) on a few occasions, and it was generally after watching or hearing about something spooky (e.g. ghosts/aliens on *Unsolved Mysteries*), and it happened when I was much older. Heck, I suppose even nowadays I could probably still make myself freak out if I think about ghosts and monsters long and hard enough, but I'm obviously it's not something I really try. =P However, one thing that *does* scare the hell out of me nowadays is earthquakes. It's not the fear of being alone though, it's the fear of being vulnerable when it happens (e.g. asleep).
Answer: Sometimes, if we try too hard to soothe and ease all their emotional reactions, we wind up reinforcing them.  Having your undivided attention and energy, as a child, is obviously preferable to not, and if kicking up a fuss makes you go to great lengths to "fix" that, then they get rewarded for it.
Not to say it's an intentional thing.  Maybe they don't like the idea of being alone, but, as with all unknown or new things, they will resist at first, but acclimate if they have to.  If they are able to get you to acquiesce instead of having to deal with that new experience, then they'll keep doing so, or even escalate.
Parents sometimes just need to develop a thicker skin about the kids being upset.  They're kids, they get upset quite easily, but they also get over stuff very quickly.  It's the upside to having the attention span of a child.  We just have to fight our protective instincts when we know it's just about being upset vs protecting them from harm.
Answer: I would like to add the perspective of one who was once a child who was very scared for what must have seemed like no reason at all. I don't know whether it will help, but my situation was similar (although to some extent less severe, I would sleep in my own room although I was actually afraid to do so) to that described by the OP. I would not willingly go upstairs by myself even during the day, once in bed I would not get out again until morning unless someone was with me etc
As a child I had a recurring nightmare about monsters which lived under my bed. This I believe is not unusual for small children. What made mine somewhat different is that I have also always suffered from very occasional episodes of sleep paralysis https://en.wikipedia.org/wiki/Sleep_paralysis, usually when very overtired or ill. When I say very occasional, I mean it has happened maybe 5 or 6 times in my life, but even now that I understand what it is, it's terrifying. As a child, I believed it was the monsters "visiting" me, and as a consequence nothing my parents could say or do would convince me they weren't real. I KNEW there were monsters under my bed, they had spoken to me and I had felt one put its hand on my chest while I was "awake" (this is a common halucination associated with sleep paralysis) they were just always hiding when my Daddy looked for them.
In my case I eventually grew out of my nightmares (there was a defined last dream where the presence of the monster made me realise I was dreaming, turning the nightmare into a lucid dream in which I drove them away, never to return) and convinced myself that the monsters probably weren't real after all, or at least had left or not followed us to our new house when we moved. It was years later when I saw a documentary on sleep paralysis that I realised exactly what I had experienced.
I'm not saying that this is the cause for every child who has this kind of phase, but just consider that what may seem rather silly to you as an adult, may seem very very real and utterly terrifying to a child who does not understand and lacks the words and confidence to express what they have experienced.
Answer: Oh poor thing. Its so hard to see your child frightened like that -and frustrating to :). All of our kids around that age became SUPER imaginative. Which can be good, but depending on what your kids are watching, what's happening in the home, and how they are feeling about themselves - this wild imagination can invent some pretty scary scenarios.
Our son, as a 4 year old, unfortunately saw "Home Alone" while playing at a friends house and he was never the same. Seems silly, but for him the idea that robbers would come into the house and try to get him became VERY real. So maybe keep an eye on what your 5 year old is watching.
Our daughter around the same age witnessed her grandfather die and it made her very scared to leave our side. She worried that if she did it might be the last time she saw us. It took her a LONG time to get over that fear and it was VERY difficult to even leave her at school, or dance, or to play at a friends. One thing we did that seemed to help was giving her something to hold on to that she knew we would have to come back for. To a child security is everything. So maybe try leaving a personal item with her - your watch, for instance, or a piece of jewelry and tell her you'll be back for it in the morning. Supposedly this helps them develop a sense of continuity throughout the night and establish a feeling of direct connection with you.
There are likely dozens of other things that could be going on in her little head. This is a difficult scenario for sure. You do definitely want her to learn to face her fear and work through it. So I wouldn't pander to it, but you must also have loads of patience and offer encouragement like you never have before. Build her up so that she thinks she is the queen of the world and capable of everything. You obviously already done the potty training bit, so you know that a little encouragement goes a long ways. Encourage her in everything and reward her for the small progress she makes as she gains her bravery back. Breaking a cycle of fear is difficult even for adults so be loving and celebrate her progress.
Good luck!
Answer: My daughter (now 10) had this same problem and still does to a lesser extent. I can only speak from my own experience, but I believe it had to do with stuff going on inside her own head. She has a great imagination, like all kids and scares herself with thinking there are ghosts in the closet or under the bed.
My husband and I never permitted sleeping in our bed, so this wasn't even considered. But she did cry sometimes. We would just soothe her and then leave her alone with a hallway light on dim.
She is still scared sometimes, but nothing major or often. I think your child will grow out of it. But I think if you let her sleep in your bed it will take longer. I may be wrong, just a gut feeling that kids will get away with what you let them get away with. Good luck with it.
Answer: I don't why she's behaving this way, but I tend to think it's readily solvable with the help of a child psychologist. I think a licensed professional would be able to get to the root of the problem and resolve it pretty quickly.
Answer: You know, children are really in tune to us as parents. My suggestion would be to try as hard as you can to simply normalize the situation.
I would tell my child " I know you are afraid of certain things. I don't think you need to be, but these are your thoughts and I respect them. You can always talk to me about anything! I won't tell you that you are wrong about your fears."
Then show respect.  Example "Susan, I am going to the bathroom to brush my hair, if you need to go and would like company, now's a good time."  "Susan it's bedtime. I would prefer you to sleep in your own bed.  Are you ready to tonight?"
If not, then " A compromise then, you can fall asleep in my bed, but yours is for you to sleep in.  I will bring you there and be sure to leave the light on for you"
My 10 y/o, adopted girl slept with a light on till she was 8. She still climbs into my bed.  She has had many fears that I simply cannot reconcile, but the less I make of them, give her respect and avoid over thinking things, the happier she is.  I always tell her, you can talk to me, and I promise to listen with my face (no phone or computer).  She can also let me know if she would like a response or if she just needs to vent.
Lights are out now, she goes to the basement alone, and more.
When we make their deals BIG deals, they get scared.  Been raising kids for 32 years.  Still learning..
Whatever you choose to do... Good luck!  And yes, it will pass.
Comment: Hi Donna - welcome. Can you please read [answer] and edit your post to be in line with the guidance there. Without reformatting and some spelling and grammar updates it is very hard to read.
Comment: Hello.  I have read, and am not sure what I am missing.
Comment: Currently your post is a big wall of text that is difficult to read. I tried to parse it to try and edit it myself, but wasn't sure exactly what you were saying.

Why is my child so scared?


Can I cause a Melacha to happen in a place where Shabbat has already started?

Question: Can I cause a Melacha to happen in a place where Shabbat has already started? For example, if I live in New York, could I send a fax (causing the machine to print a document) to Israel on Friday afternoon, before it is Shabbat for me, but after Shabbat has started there?
Comment: @WAF The line of sunset moves at around 1,000 miles per hour, so doing that would be virtually impossible without sophisticated equipment to detect the moment of sunset to within 10 milliseconds.
Comment: Related: http://judaism.stackexchange.com/questions/11070/am-i-allowed-to-view-a-kotel-cam-on-shabbos
Comment: Is this any different from a case where I throw a stone from a time zone where it is not yet _shabas_ into a time zone where _shabas_ has already started?
Comment: @Ariel Nobody said it would be easy. . . My question was just whether a theoretical analog exists.
Comment: I'd just like to note the possibility that while you didn't do a Melakha (which is pretty obviously true), Shabbat might still be Mechullal, which would be at the very least, sad.
Answer: The Shut Ohr Yizchak (Ohr Hachaim 157) says that not only it is OK, but the question not even starts ("he did nothing"). The example he gives is to call from Israel to the States on Motzei Shabat. In Israel it is after Shabat and in the States the Shabat is still on. He adds that it is even permissible to phone a non Jew and ask him to do work for you.
I read a shiur that discusses whether the commandment to rest on Shabat is for the Jew or for Creation (World?). For those who are of the opinion that the commandment is for Creation to rest, this will not be permissible. The Grm"o Fraind is brought as a posek that follows this opinion, but the majority of the poskim permit it.
Comment: It should be noted that although it is permitted to send it, it is questionable whether the receiver may read it. I believe it involves an issue of molad...
Comment: What work are you referencing as the source here? Can you give some information about it or a link?
Answer: Rav Hershel Schacter discusses a Kasav yad of the Rambam which could assur such ideas.  http://www.ou.org/torah/article/let_my_people_know inyun starts at 8:50 where he discusses this peirush HaRambam and Rav Moshe on setting up something that causes a melacha on Shabbas and he comes out that l'chumra it should not be done and the OU tries to avoid sending emails where it is shabbas somewhere else.
Answer: If you send a fax on Friday (before sunset in your timezone) to Israel, or anywhere else in the world, such that it is after the Sabbath has commenced in that time zone, then you are causing the same amount of work to be done as setting electronic timers to turn off and on the lights during the Sabbath. So like @rony says, if you find that degree of activity to be acceptable, the electromagnetic activity generated by transmission of a fax, and the electro-mechanical activity of the fax machine applying heat or ink to paper and producing the fax, then it is acceptable. It means that you are of the opinion that the Sabbath is not for all Creation to rest.
As another said, the fax will certainly not be read by an observant Jew who receives that fax during the 24 hour interval of the Sabbath. It will just sit on the fax machine untouched. Once the recipient is able to read the fax, he or she will not  contact you until after the Sabbath wherever you are. So there seems little point in sending the fax until after the Sabbath in your time zone, if it is regarding a matter for which you want to transact business with the recipient.
The reverse scenario would be equally applicable. You are in some part of the world after the Sabbath has ended. You then telephone, or fax, or send an email, to someone in a timezone where it is still Sabbath. The action is not an issue, a wrong action in its own right. But there should be no expectation of any response, neither answering the phone, nor reading of the fax or email and acting on it, until the Sabbath has ended for the recipient in their time zone, however many hours it is behind your time.
Final scenario: Let us assume that the recipient needs the fax to transact business with a third party. In that case, sending the fax so that either the recipient can act on it after sunset on Saturday, or a non-Jewish employee of the recipient can act on it during the Sabbath (and transact business with other non-Jews, on the Sabbath) is acceptable.
Comment: I recall the term Shabbos goy, but am not sure if that is a pejorative expression. The Shabbos goy is the equivalent of the non-Jewish employee who does work on the Sabbath while the Jewish person doesn't. I don't see it as pejorative, because the Jewish person would be doing work on Sunday while the Shabbos goy had his day of rest (or any day that the non-Jewish i.e. Shabbos goy person wanted as a day of rest, other than Shabbat).
Answer: Shmiras Shabbos Kehilchasa chapter 31 siff 28 quotes Rabbi S.Z. Aurbach as saying this is allowed.
He also quotes him as saying the Jew who recieves the fax may not read it.
I asked Rabbi Dovid Feinstein about this once and he said one may not send a fax from America to Israel once it is shabbos for them.
Comment: Sounds from this answer (and a couple of others) that you had a significant shaychus with R' Dovid Feinstein ztz"l. Are there any divrei zikaron and/or lessons that you would consider sharing with us on Chat?
Comment: He was seemingly one of the most uncomfortable people in his own skin who would've much rather hidden inside his gemera, away from the world. Any interaction he had with anyone, whether saying a shiur or answering a shaila, was literally him doing it out of kindness because he realized people wanted that interaction with him. I honestly felt bad talking to him sometimes, but Torah hee vililmod ani tzarich. He was kind and cordial, of course, but this aspect of his personality was just something that I picked up on and some family members of his mentioned by the shiva as well.


Help to recover accidently deleted calendar data

Question: OK so I have a lot of appointments in an outlook calendar (about 12 each day). It was synced to my Galaxy 3G. I wanted to delete all of them for one day, so deleted multiple appointments but I didn't get the option to specify whether I wanted to delete a single event or a recurring event - and as a default it deleted all recurring events (hence all of my future appointments .. lots!).
I decided to sync with my outlook calendar thinking that it would replace all of the deleted appointments, however it synced in the other direction and has wiped them all from my outlook calender as well as my phone calender.
Really could do with some advice how to 'undo' the delete on the phone or where else I may find the original data to recover it (I have looked at the outlook calendar and the data is not in the trash as it would be if I had deleted the data via outlook itself).
Answer: This question is related more to Outlook than Android. Android syncs with google calendar and even if that case, deleted calendar events cannot be recovered (Google Support -
Can I recover a deleted Calendar event?  You can try to:

Go to your deleted folder in Outlook (yes I mean deleted mail) and check if deleted events are there. After deleting they go to this place.
Check if you have any Outlook backups
Check if you have any android backups, maybe you use Titanium Backup or similar software?

Other than that I can't think of any other way of restoring your calendar events


How am I anonymous and safe with my config?

Question: I have got ThinkPad T400 with coreboot and minimal OpenBSD installation with full-disk encryption. All non-Tor traffic is dropped by pf. Only allowed traffic on the host is torified traffic from package manager, gpg, git and traffic from virtual machines. I set up Whonix-Workstation inside virtual machine and Whonix-Gateway on separate device. ThinkPad works without battery on AC power. I use open-hardware router. Is it a good setup for anonymous using internet?
Answer: As far as it goes it sound good.
Make sure that you follow the projects recommendations for browser settings.  There are also various add-ons that can both increase anonymity and make the browser more useful.
If you install any other software, make sure that you have done a search on the "make and model" to verify that it has not been hacked.  To be truthful I would not add any software that has not been vetted by the project in some manner.
Comment: i strongly advise against installing addons in Tor Browser on your own: https://tor.stackexchange.com/q/8832/5234


How would an artist be able to sell their own music for Bitcoin?

Question: What options are there for artists to market their Music in exchange for Bitcoin? How would an artist be able to directly sell his work to his fans?
Comment: This is a fantastic question. I've got a client who is a well known artist and I've yet to push the Bitcoin integration because Coinbase essentially handles the whole situation. I'd love to know if being the *middle man* in setting up BTC payments was worthwhile or if Coinbase/Bitpay is the only real option.
Comment: It rather depends on if you are a signed artist or not. Signed artists have to go through the various processes of collecting and distribution, unsigned artists are free to set up a simple Bitpay account for example, and generate direct sales online. If not you could print a QR on your merchandise or something like that.
Answer: Regarding this question, its probably worthwhile to check out Bittunes. The company was started in May 2013 with the mission to enable the monetization of file sharing with Bitcoin. The significance of this is that it is not about just using Bitcoin as a way to buy music, but actually incentivising buys (fans) to serve as a new kind of distribution channel for music. ~ In other words, its an 'earning platform' for both artists and fans. It is early days for the system, with many aspects still to roll out. see:  www.bittunes.com and www.bittunes.org for more detail.
Answer: Liberty Music Store is a place to buy and sell music with Bitcoin. It is geared towards simple user experience. The artist can keep 100%.
(disclaimer: I am the author)
Answer: If I was an artist, I would have bitpay integrated to my Website, or direct people to an online store like Cryptothrift where my song would be listed and they can purchase it there with bitcoins.


Comparison of Octave, Spyder, Freemat and Scilab as alternatives to MATLAB

Question: I am trying to find an alternative for MATLAB and have so far found:

GNU Octave
Spyder
FreeMat
Scilab

I'm trying to find which is the best alternative to MATLAB. I'm particularly concerned with performance and the integrity of the results.
Comment: You should also consider R. [This question on StackOverflow](http://stackoverflow.com/questions/1738087/what-can-matlab-do-that-r-cannot-do) probably has the best comparison
Comment: [IPython](http://ipython.org) is missing
Answer: Well you're in for a treat I have used all the programming languages/software you mentioned. FreeMat and Spyder I do not have too much experience with, but I have some. The others I am experienced in.
GNU Octave by far beets the competition. Its syntax has an extreme compatibility with that of MATLAB. The only differences, I'm aware of at least, aside from the odd toolbox, which you can attempt to replace by the packages here is that GNU Octave can define functions from the command line.
I don't know if you're aware of QtOctave. QtOctave is a frontend (GUI) for the GNU Octave programming language. QtOctave comes with an editor too.
Scilab is an adequate replacement for MATLAB too. It has some differences in terms of syntax but nothing you can't get your head around if you search the documentation that comes with it.
FreeMat is the worst, in my opinion at least, of software that's syntax is heavily based on MATLAB. My evidence for this is three part: firstly, in the software centre it receive the lowest star rating of the four software in question. Second, it isn't frequently updated, the latest version in the software centre, was last updated in 2008. Third as a result of my second piece of evidence its functions are somewhat lagging. The plus side, however, is that its syntax is highly compatible with MATLAB's.
I have used Spyder, but only briefly I'm afraid. It seems top-quality. The problem with it is that it has only limited compatibility with MATLAB, syntax wise. It requires you to learn some of the Python programming language, that is, if you plan to do well at it.
I would also recommend SageMath as it includes GNU Octave, (if its already installed on your system) Scilab, (if you already have it installed) NumPy, [NumPy and the rest mentioned unless otherwise specified come with Sage and therefore no installation is necessary] Scipy, Matplotlib, maxima, Fortran among many others. SageMath may be downloaded by going to the website http://www.sagemath.org/download-linux.html and selecting a suitable mirror, based on where you are and then installing the relevant .tar.lzma file. After this copy and paste the following commands into terminal (Ctrl+Alt+T):
cd ~/Downloads
sudo mv sage-linux-xbit-ubuntu_y-z-Linux.tar.lzma /home/username
cd ~
tar --lzma -xvf sage-linux-xbit-ubuntu_y-z-Linux.tar.lzma
cd ~/sage-linux-xbit-ubuntu_y-z-Linux
make
sudo ln -s /home/username/sage-linux-xbit-ubuntu_y-z-Linux/sage /usr/local/bin/sage

Where 'x' refers to the bits of your OS; 'y' refers to the version of Ubuntu the sage is designed for (e.g. 10.04_lts; 12.04_lts (the _lts is required in 'y'), etc.); 'z' refers to the architecture of your OS. (i386, amd64, etc.)
Answer: Of all the ones you have listed Octave is the most syntax compatible.  In fact, apart from some of the expensive Matlab toolboxes, Octave should run 98% (a number I just made up) of your code.  I use Matlab at work and Octave at home.
Octave will not run (natively) some of the inbuilt GUIs like inputdlg etc, if you install Qtoctave (an IDE for Octave, sudo apt-get install qtoctave) you can use xmlwidget and a wrapper to get that functionality (I can post code if you are interested).
As far as performance is concerned, Octave is not as fast (google for benchmarks).  However, you can get all modern versions of Matlab running on Linux (if you have a licence) and they are included on the install disk by default now, and performance of Linux version of Matlab is as good and often better on Linux when compared to Windows.
If you want performance and you wan't to use free software best to look at scipy.  But the syntax is less compatible.  You will need to rewrite you code.  Spyder is an ide that uses python and scipy, scilab is a mash of octave and maxima and a few others.  Not sure about performance of freemat but I don't think it is as developed as Octave.
Good luck.
A few benchmarks
speed
http://www.osc.edu/research/cse/projects/octave_python.pdf
http://www.wseas.us/e-library/conferences/2010/Corfu/COMPUTERS/COMPUTERS2-56.pdf
Remember benchmarks are subjective.  There are many variables.  The only true way to know is to test them all on your rig using your processing code.
Comment: If someone does google and find good benchmarks for Octave vs. Matlab, perhaps more detailed information or links could be edited into this answer.
Answer: Just for clarification: Why do you want an alternative for Matlab? The answer of prasadkumar013 suggests you can't use Matlab on Ubuntu, but you can (at least I am running it on Ubuntu ;) ). There is a community documentation on the page https://help.ubuntu.com/community/MATLAB.
In case you want a free alternative go with octave, most of the matlab code will work directly in octave. Try to work in the terminal though, the qtoctave GUI was not so user friendly in my opinion.
Answer: Most similar to MATLAB = Octave, (link to gui  )
An awesome up-and-coming high-level computation language = julia
But my favorite and IMHO most useful all around language, PYTHON (scipy, sage, cython...)
Answer: This is nice paper.
It has brief explanation and various tests done.
BTW I don't use MATLAB or anything like that.
Answer: http://pdl.perl.org/
PDL ("Perl Data Language") gives standard Perl the ability to compactly store and speedily manipulate the large N-dimensional data arrays which are the bread and butter of scientific computing.
Answer: Have you already tried Sage (www.sagemath.org)? It's a container for different mathematics software and it can do symbolic and numerical calculations. The latter ones are done using numpy and scipy.
It has a very active community and it's an open source project written in python.
Since you're interested in performances, here there are some benchmarks (at the end of the page also comparisons with Matlab).
Answer: I have not done a real comparison but in my experience purely form a performance perspective octave is better than MATLAB.
You should note that "it is all relative" different toolboxes have different performances.
If you have limited RAM on your machine I would say anything would work better than MATLAB.
Answer: My college uses MATLAB on their Windows PCs. But for using MATLAB on Ubuntu I had been left with two choices

Install MATLAB over wine or any virtualization software
Find a Linux Equivallent

As virtualization is very heavy on my laptop, I searched for an alternative. After many software trials, I finally settled for OCTAVE. It can run most of the standard MATLAB codes. Instead of GNU Octave, it is better to go for qt Octave. While the former is terminal based, the later is GUI based.
My choice is to go for qt Octave
sudo apt-get install qtoctave
Comment: A third choice would be to [**install the Linux version of Matlab**](http://askubuntu.com/a/152426/22949).


Best way to reheat pizza

Question: Whats the best way to reheat leftover pizza? We usually use Boboli Crust with our own toppings, or sometimes we have frozen pizza.
Comment: Oh you're missing out -- cold leftover pizza is quite the treat! In fact, I look forward to having leftover pizza just so I can eat it cold the next day.
Answer: @Cos is right, a pizza stone is great - so is a pizza screen in the oven.
If I don't want to heat up the oven (big oven, little piece of pizza aways seems like a waste), then a cast iron pan over medium heat on the stove with a lid does pretty well.
Comment: definitely like this idea for small jobs (1-2 pieces)
Answer: I have always had the most satisfactory results from preheating the oven to 400F with a pizza stone and then setting the cold pizza on the hot stone for 8 to 10 minutes?
Answer: If you just want to reheat a slice or two, you can warm it in the microwave for 30 seconds to a minute and then put it in a toaster oven on toast or a hot oven setting for a few minutes. It's best in the toaster oven if you put the slice(s) on the broiling rack on top of the baking sheet.
Comment: @philosodad: the toaster oven more or less cancels out the chewiness that the microwave would add. The microwave/toaster oven approach is definitely about balancing convenience with quality. The toaster oven alone gives a somewhat better overall result but takes longer.
Comment: I'm going to heartily recommend *against* the microwave. Seems to make the crust chewy.
Comment: @amcnabb You are right. The combo of both the toaster oven and the microwave is key (microwave alone means it comes out chewy and soggy, toaster alone is either burnt or not heated all the way through) - together the microwave quickly warms it and the toaster oven undoes the sogginess created by the microwave - making it golden brown and delicious.
Answer: Since I prefer thin crust pizzas, oven re-heating often results in something resembling a burnt cracker with some half-cold toppings on it.
To avoid this, I "fry" leftover pizza to reheat it: I place a tiny bit of oil or butter into the bottom of a non-stick skillet, add slices of pizza, cover, and place over very low heat until the cheese is re-melted.
This method allows the pizza to warm and steam gently, while also ever-so-slightly frying the bottom of the crust, so one ends up with something very near the consistency of a fresh slice rather than a dried-out, inconsistently-warmed leftover.
This technique works with everything from thin crust to deep-dish pizza; only the reheating times are different.
Answer: I like to put a heavy sheet pan in the oven and preheat it to 350°F. Then I just slide my leftover slices onto the hot pan and bake for 5 minutes. The hot pan crisps up the bottom of the crust and the hot oven does the rest. Does a nice job of bringing a good slice of pizza back to life.
Answer: I found that a short burst in the microwave heats up up the whole piece. Then, you have to  immediately put it into a very hot oven to get it crispy on the outside. (You said "the best way", not the most energy efficient.)
Answer: I use an oven at 250°F for a longer period of time--usually about 15 minutes, with the pizza either in or on tin foil. This seems to work well, it heats the pizza but doesn't toast the crust.
Comment: I hope you mean 250 F, not C.
Answer: Pizza stone on 350 for 10 minutes. Or if your lazy and don't own a pizza stone, like me, toaster oven on toast for however long it takes too heat, crisp up and not burn.
Comment: Welcome to the site! It seems your answer doesn't contain a new suggestion - if you agree with what others wrote, you would upvote their answer(s), not repeat it. On the other hand, if you can *explain* in your answer *why* your approach is the best, it might be interesting.
Answer: With a waffle iron!!!
Leftover Pizza + Waffle Iron = Delicious Crispy, Gooey, Cheese-Stuffed Snack
Answer: For larger amounts of leftover frozen thin crust pizza- Line a medium/large baking pan/sheet that has at least 1/4 inch vertical sides on it with tin foil. Use middle rack. If two baking pans are used, use rack positions 1 and 4. 1 being the lowest rack, 4 being the higher one. Preheat oven on Convection/Bake at 425F to 450F. After preheating oven,  place frozen thin crust pizza on baking pan/s. Put pan/s in oven and heat for approx 30 minutes. Check at 20 minutes to make sure not to over cook. Enjoy!

Best way to reheat pizza


Does the drying out of vegetables affect the taste after cooking?

Question: If I cut the onions and vegetables in the morning, they dry up till evening. Is there a taste change when you eat cooked vegetables, which dried out over 8 hours (before cooking)?
Comment: Since it sounded unlikely that you were dehydrating thevegetables (to my ears anyway), I edited to reflect drying out over the course of the day; feel free to hit roll-back if that is not what you were talking about.
Answer: 8 hours in still air is probably not going to be enough to thoroughly dry your vegetables.
If you live in a very dry climate and the veggies were sitting uncovered in front of a fan the entire time then you might have actually dried them.
So your title is asking a different question than your description.
Description:
If you live in a very humid climate then you might be more concerned about spoiling than drying. They may have become a little limp so it makes a difference how you plan to cook them. If the veggies are going to be diced and sauteed and used in something else then they will probably be fine. If they are going to be their own side- like steamed asparagus- then the texture may be decidedly un-fresh.
Either way- the flavor will be normal or close to it.
Title:
Actual dehydrated veggies are different altogether. They have had most of their water removed. This concentrates flavors and changes them. They are sweeter and more intense. Their texture is also firmer and ranges from crisp to rubbery to almost normal depending on how much they are rehydrated.
Answer: I don't think the water change will be very significant. If you were to lay them out flat so the surfaces dried a bit, they might sear and brown more easily (because that effect depends on moisture reduction in the first millimeter or so of the vegetable so that it can go above 212 F). The other thing that can be a factor is that once a vegetable is cut, some enzymes are released from the cells that can cause changes. Whether that effect will make any substantial difference depends a lot on which vegetables you are talking about.
Comment: Some vegetables do quite well stored in water after cutting. It reduces oxidation and drying out, but it can also cause flavor and vitamins to leach out, so it is a bit of a mixed bag.
Comment: Thanks, if I put those vegetables in water will that help? Or water is not helpful for some certain type of veggies?
Comment: I'll use that water in cooking, so vitamins loss is not a problem. I want to try it with spanich.
Answer: If you're eating them raw, or if they tend to oxidize (like avocado, for example) then yes, you may notice a difference.
Otherwise, you're just losing a bit of water. No big deal.
Comment: @anisha: Yea, when they turn brown? If you were cutting up potatoes, I'd definitely tell you to put 'em in water. Avocado, I'd just tell you not to cut up (lemon juice works, but it changes the taste, obviously). Onions and peppers would be fine.
Comment: @I know about potatoes, but should I put the lady fingers too in the water for keeping them fresh?


How can we implement controlled-T gate using CNOT and H, S and T gates?

Question: In general, is there any way to implement a controlled version of an arbitrary gate U if we are given only CNOT and U gate?
Comment: An observation that might be helpful: any arbitrary controlled-U gate on two qubits can be written as: $\text{controlled-}U = |0 \rangle \langle 0 | \otimes \mathbb{I} + |1 \rangle \langle 1 | \otimes U$. But that doesn't automatically tell us how to express the full controlled-U gate in terms of elementary gates...but I'd start by writing U in terms of basic gates and then go from there.
Answer: We can implement $CT$ using the following circuit:

This solutions uses an extra gate which isn't available above $R_I(\pi/8) = \sqrt{T}$
Explanation:
We know that $T = \sqrt{S} = Z^{\frac{1}{4}}$.
Since $S,T,Z$ are all diagonal matrices hence their controlled versions will also be diagonal matrices $CZ,CS,CT$. Thus $CT=CZ^{\frac{1}{4}}$.
If we can implement the fourth root of $CZ$ using the above gates we will have a $Controlled-T$ gate.
We can implement a Controlled $Z$ gate using $CNOT$ and $H$ gates
$$CZ = |0\rangle\langle 0|\otimes I + |1\rangle\langle 1|\otimes Z \\
= |0\rangle\langle 0|\otimes HIH + |1\rangle\langle 1|\otimes HXH \\
= (I\otimes H)(|0\rangle\langle 0|\otimes I + |1\rangle\langle 1|\otimes X)(I\otimes H)\\
= (I\otimes H)CNOT(I\otimes H)$$
We can implement $CNOT^{2t}$ gates using the circuit show in Craig Gidney's Answer

We need $CNOT^{1/4}$ hence $t=\frac{1}{8}$. This requires $Z^{\frac{1}{8}}$ i.e $R_{I}(\pi/8)$ and its Adjoint gate.
Let $U = (I\otimes H)CNOT^{\frac{1}{4}}(I\otimes H)$, then
$$U^4= UUUU \\
= (I\otimes H)CNOT^{\frac{1}{4}}(I\otimes H) \times (I\otimes H)CNOT^{\frac{1}{4}}(I\otimes H) \times (I\otimes H)CNOT^{\frac{1}{4}}(I\otimes H) \times (I\otimes H)CNOT^{\frac{1}{4}}(I\otimes H) \\
= (I\otimes H)CNOT^{\frac{1}{4}}CNOT^{\frac{1}{4}}CNOT^{\frac{1}{4}}CNOT^{\frac{1}{4}}(I\otimes H) \\
= (I\otimes H)CNOT(I\otimes H) \\
= CZ$$
Thus $U = CZ^{\frac{1}{4}} = CT$
In general for implementing $Controlled-Z^{\frac{1}{2^n}}$ gate we would need $H$, $CNOT$ and $Z^{\frac{1}{2^{n+1}}}$(along with its adjoint version) gate.
Answer: You can use Toffolis and an ancilla to remove the need for the control on the T, then decompose the Toffolis into T+H+CNOT. Since the second Toffoli is uncomputing the ancilla, it can be replaced by a measurement based uncomputation.
Answer: In general you need more than $U$ and CNOT to implement a controlled-$U$.  One approach to constructing a controlled-$U$ gate, for arbitrary $U \in \mathbf{U}(2)$, from single qubit and CNOT gates begins by parameterizing $U$ in terms of $U(\alpha,\beta,\gamma,\delta)$ according to
$$U = e^{i\alpha}\begin{bmatrix} \exp\left({-i\frac{\beta+\delta}{2}}\right)\cos \frac{\gamma}{2} & -\exp\left({-i\frac{\beta-\delta}{2}}\right)\sin \frac{\gamma}{2} \\ \exp\left({i \frac{\beta-\delta}{2}}\right)\sin \frac{\gamma}{2} & \exp\left({i\frac{\beta+\delta}{2}}\right)\cos \frac{\gamma}{2} \end{bmatrix}.$$
With this parameterization, $U$ can be decomposed in terms of the Pauli matrices $\sigma_x, \, \sigma_y, \, \sigma_z$ as
$$U=e^{i\alpha}A \, \sigma_x B \, \sigma_x C, \;\;\; A \equiv e^{-\frac{i}{2}\beta \sigma_z}e^{-\frac{i}{4}\gamma \sigma_y}$$
$$B \equiv e^{\frac{i}{4}\gamma \sigma_y}e^{\frac{i}{4}(\beta+\delta) \sigma_z}, \;\;\; C\equiv e^{\frac{i}{4}(\beta-\delta) \sigma_z}.$$
The usefulness of this decomposition is that $U$ can be expressed as above, while $ABC=I$.  Defining one additional gate $$D=\begin{bmatrix} 1 & 0 \\ 0 & e^{i \alpha} \end{bmatrix}$$ allows circuit implementation of an arbitrary controlled-$U$ using four single qubit gates and two CNOT gates as

In the specific case noted in the title, $U=T$, the parameterization is $\alpha=\beta=\delta=\frac{\pi}{8}$, and $\gamma=0$.  This gives $A=e^{-\frac{i \pi}{16} \sigma_z} \cong \sqrt{T} $, $B=e^{\frac{i \pi}{16} \sigma_z} \cong \sqrt{T^\dagger}$, $C=I$, $D=\sqrt{T}$ (where $\cong$ indicates equivalence up to global phase).  It seems that you need access to $\sqrt{T}$ gates to implement the desired controlled-$T$.


Change Request to change scope

Question: We're running a project and we come to conclusion that the approach used in the project to handle the business issue is not performing as expected. We're changing the scope of the project to meet the business requirements. Should a change request be raised? Who should write it, if needed?
Answer: A change request or contract modification is certainly in order in this scenario. I'm assuming that the running of the project is part of a contract, so in almost all cases a significant change in scope would require the mod. If the contract is time and materials this may not be the case, but as a Project Manager it is important that you keep your customer informed, and in this case a new scope would be an important thing to discuss with them.
As for who writes up the modification, it would depend some, but traditionally this is the responsibility of you the contractor. You may need or want input from the customer so that you both know what the impact and expected outcome of the case of scope entails, but ultimately since you have to accept the new work it's on you to write the mod.
In the extreme, this scenario may be grounds for vacating the existing contract completely and starting with a new one that covers the specific appropriate business need.

Change Request to change scope


Is a "house-rules all-call" appropriate for this site?

Question: I confess: I've been doing some tweaking to the games I've been running and I'd be proud to share them here. In exchange, I'd be interested in seeing what cool modifications others have come up with. Is it appropriate to start a community-wiki thread with a title like "What are your GAME X house rules and modifications?" and let people go to town, or is something with such little guiding focus better for another site?
Answer: I really don't think that such a question, even on a per system basis would be very useful to anyone.
Such a question might be ok if

It was community wiki.
It was system specific
It was asked with regards to a specific mechanic.

ie:

What are your house rules for differentiating firearms damage in d20 modern?

Basically, keep the questions specific.
Comment: I think specific questions are always the best way to go.
Comment: I disagree. Part of Stack Exchange is to act as a wiki as well as as a place to get questions answered. It not just a Q&A site but repository for expert knowledge about a subject. A collection of house rules for a system is part of this. Trying to limit these type of posts it a specific mechanic is too narrow.
Comment: @Numenetic I think we should enforce them to be limited to a system unless it is really obvious that there needs to be a sub category. In practice I think we will find that only the major editions of D&D will have enough traffic to warrant this. And we should only worry about the sub categories once the traffic actually materializes. To do otherwise will annoy new users.
Comment: I agree - CW and tightly scoped only.  It's OK to do it, but it turns into worthless noise if not scoped - a SE Q&A is NOT a proper wiki that can be organized and sub-paged.
Comment: @RS Conley--Wouldn't keeping the questions at least somewhat specific help keep that repository organized?  We can't tag answers, so there's no way for someone to sort through the wide variety of house rules if they're all lumped together.
Comment: @RS Conley: Agreed--My D&D orientation was coming through there, I think.
Comment: I think RS Conley has a point about scope depending on the game: house-rules for any mechanic for a game like Zenobia could be all in one question without becoming unwieldy. However, that becomes hard to judge. Better to go with specific as default, since we can merge but not split later.
Answer: Your question is why the community wiki feature exists. The only suggestions I have is limit each post to one system as it will help fans of that system find the posts easier.
Answer: Personally, I would rather have system+topic specific questions, but that may just be personal preference.  I think that as long as it doesn't duplicate an existing question (there are a few houserule CWs out there) that it wouldn't need to be closed.  People can vote on it to express preference for such a general question.
Answer: I'd much rather see a question like, "Where can I go on the net to find lists of house rules?"
Answer: Hosue rules is a problematic tag only because it requires another tag to exist. Theres a good policy on stackexchange to avoid tags that can't surive on their own and are subjective (http://blog.stackoverflow.com/2010/08/the-death-of-meta-tags/). Hosuerules probably qualifies and we should remove it as a result.
Comment: so if a person wants to look up various house rules for GURPS on the Stackexchange how do they go about this?
Comment: I completely disagree. House rules is a perfectly well defined and commonly understood concept in roleplaying games.


How do tariffs work?

Question: When a foreign company wants to export their goods to the U.S. they may encounter a tariff (e.g. steel). The tariff is imposed by the U.S. government at the port of entry and is a form of tax revenue. However, does the exporter's revenue take a hit or do they simply charge the importer more to take the cost of the tariff into account? Does it just depend on whatever agreement the exporter/importer come to?
Answer: Assuming a competitive global market,
If an importer would by steel in the global market in global prices, he will have to absorb the tax cost at importing, then roll it to its customers at home
The exporter will not absorb the tax, since it can sell to other countries without it.
If the importer's country is big enough market-wise, then:
some tax absorption on the exporter's side might take place since the exporter will lose large sales if no absorption is made,
And the importer will not roll all the tax to its customers since competing importers, might receive the same tax-absorption sharing with exporters (theory dictates it, all are equal in a competition),
In this case, a lower price from competitors will lead to a loss of market share
Comment: תודה שענית על השאלה שלי גיא.
Comment: @user27343 בשמחה
Answer: In most countries and from a fiscal point of view, the exporter is the one who assumes the tariff, since it is the cost imposed by the country to allow the entry of foreign goods.
However, it is possible that the exporter increases the price of his good, in order to divide the cost of the tariff between him and the importer.

How do tariffs work?


How to run workflow on updated list item in sharepoint designer?

Question: I want to stop the workflow which in progress or pause and restart the workflow when item is edited. lets say i have created one item, workflow starts in progress. Now i want to edit the list item. i do it but my workflow is still running on old items not on updated or edited items. please guide me. how can i achieve this.
Comment: You can terminate the workflow that is running...
Answer: As my Knowledge you can create Two workflows on same list one is Start when "start when an item is Created" and second workflow is When "start when an item is changed" by SharePoint Out Of Box.
Answer: Don't know if I got your question.
First, you should create a second workflow, set it to "start when an item is changed". Within this workflow you can access your up to date data from within the item every time it is changed.
However you cannot stop the workflow started by "item creation workflow" from within the "item changed workflow", at least not with SharePoint Designer.
Answer: I think you can use event handler associated with item for item changed. Every time an item has been edited, check whether a workflow instance is still running. If so, cancel the running workflow. This link would help you. http://chrissyblanco.blogspot.com/2007/08/cancelling-running-workflow.html
If you don't want to go for coding, you can try below approach, SP designer workflows have this behavior that they do not stop when the item is updated.
Create 2 lists (parent and child) and a workflow on each (wf1 and wf2) respectively. When your condition meets in the workflow(wf1) of parent list, create an item in child list on which the wf2 workflow starts and pauses till the specified date. Once the pause is completed, you can send the mail from workflow 1 or 2 and then delete the item in child list.
Modify your Parent list workflow to handle the below scenario. If you ever update the item in parent list, delete the corresponding item in child list that was paused/waiting and create a fresh one.
You need to store the fields Parent list Item ID, version(optional).
Parent list is your actual list. Child list is a staging one which you never expose to anyone.


Could a FOSS autopilot system ever pass FAA regulations?

Question: Think something like ardupilot but for manned aircraft.
Comment: I doubt it, it could possibly be used in Experimentals, but there are manufacturing, quality control, and testing requirements that would be difficult or impossible to manage with public contributions.
Comment: Since FAA does not force the source code to be confidential, so the owner of the code has full freedom to license it to whoever under whatever license. So while hobbyists developing such systems from scratch is hard, vendors developing it in house and open it to the public is highly possible. In fact I would say most of the contributions to FOSS are funded by vendors not volunteers.
Comment: [Closely related](https://aviation.stackexchange.com/q/36853/62). In particular, [this answer](https://aviation.stackexchange.com/a/36860/62) might help you. I don't think we can really say if it will "ever" happen, because that's speculation and we don't know how/if the rules will change in future.
Answer: Short answer: technically and legally yes, a free open source autopilot could be certified.  But I think it is unlikely to happen anytime soon.
Long answer: Aircraft software certification is governed by DO-178C. There is nothing in there that says anything about whether the source is open vs closed, or free vs non-free.  What it does lay down is a lot of very rigorous requirements for proving that the software does what it says it is going to do.
For example, for something like an autopilot, an independent testing/validation would typically be required.  That means the person who writes/codes the software and the person who tests the software have to be different people. i.e. you must have a fresh set of eyes looking at it. Further that testing will have be very extensive, covering every possible scenario your autopilot could encounter.  You might have to mock up an entire fake airplane, with simulated sensors and simulated actuators, and feed the autopilot simulated data and see if the actuators move like they are supposed to.
You also need to provide a massive amount of very careful documentation about all parts of your software process.  E.g. the software requirements need to documented, and then you need to be able to show every step of the way on how each specific requirement gets translated into the final machine code.
An free open source project certainly could meet all of these requirements. However, they end up being very time consuming and expensive. You need an army of software engineers working all day every day for years to meet some of these requirements.  FOSS project typically do not have the level of manpower that is required to meet these requirements.
Comment: As a software certification engineer, this is a very good answer. The trick with most FOSS is that there are not documented requirements that trace to design or test. It's impossible to show that a piece of software works correctly and has no untested code if the requirements aren't there to verify the code against.
Answer: There is no practical way for Free Open Source Software to be used in any FAA certified equipment. This approach to software development encourages users to modify and contribute code, so as to benefit the entire community. Much of the motivation is to see the code improved and put into use.
FAA certification requires such extensive testing and documentation that revisions do not occur except to correct a serious flaw, and this usually means removing the hardware and returning it to the manufacturer. New functionality might require a new generation product. It is not likely that a five or ten year wait for new features would be attractive to FOSS developers.


Why is this date in my sitemap "invalid" according to Google

Question: My XML sitemap file has <lastmod>2013-07-06T09:39:51-0400</lastmod> formatted with W3C Datetime Format.    Google has a warning message in webmaster tools about this for me:

Google's help document about error sitemap errors states:

This could be because a date is in the incorrect format, or the date itself is not valid. Dates must use W3C Datetime encoding, although you can omit the time portion if you wish. For example:

2005-02-21
2005-02-21T18:00:15+00:00
Answer:
2013-07-06T09:39:51-0400

The W3C datetime format includes a : (colon) in the time zone offset, separating the hours and minutes. So the last bit should read: -04:00.
Answer: just make sure there will be no space in between a single space will give invalid date or something error like that.
for example

2005-02-21T18:00:15 +00:00 -- space in between
2005-02-21T18:00:15+00:00  -- no spaces here valid markup


resilience to sybil attack - public vs private

Question: it appears that although not totally water-proof to Sybil attacks, Bitcoin network seems quite resilient to these kind of attack Preventing Sybil attacks. Is it true to assert that permissioned or private blockchain are less exposed since there is a certain level control of the participant allowed to enter the network ?
Answer: Definite yes.
The Sybil attack in computer security is an attack wherein a reputation system is subverted by forging identities in peer-to-peer networks.
If nodes are required to prove their identity before they can join the network, just like in permissioned or private blockchains, they will not be able to forge the identities.