How to upgrade Apache 2 from 2.2 to 2.4 for Ubuntu 10.04

Question: I was in the process of doing a test upgrade from Apache 2.2 to 2.4.3. I'm using Ubuntu 10.04. I would have upgraded to 12.04 for this to see if the upgrade would go a lot smoother. Unfortunately, I was told it wasn't an option...so I'm stuck using 10.04.
The process I did this was:
Before attempting this, I have managed to upgrade APR from 1.3 to 1.4  and APR-UTIL since apache has said they were prerequisites beforehand: http://apr.apache.org/download.cgi. I took the apr and apr-util and placed them under httpd-2.4.3/srclib
I have also taken Schlauberg's advise concerning libapr removal. So I removed all traces too when I removed all traces of the current apache.
First remove all traces of the current apache:
sudo apt-get --purge remove apache2
sudo apt-get remove apache2-common apache2-utils apache2.2-bin apache2-common
sudo apt-get autoremove

whereis apache2
sudo rm -Rf /etc/apache2 /usr/lib/apache2 /usr/include/apache2

Afterwards, I did the following:
sudo apt-get install build-essential
sudo apt-get build-dep apache2

Then install apache 2.4 with the following:
    wget http://www.bizdirusa.com/mirrors/apache//httpd/httpd-2.4.3.tar.gz
tar -xzvf httpd-2.4.3.tar.gz
cd
wget     http://mirror.olnevhost.net/pub/apache//apr/apr-1.4.6.tar.gz
tar -xzvf apr-1.4.6.tar.gz
mv apr-1.4.6 apr
cd
wget     http://mirror.olnevhost.net/pub/apache//apr/apr-util-1.4.1.tar.gz
tar -xzvf apr-util-1.4.1.tar.gz
mv apr-util-1.4.1 apr-util
cd
Place folders apr and     apr-util under /httpd-2.4.3/srclib
    sudo cp -r apr-util ~/httpd-2.4.3/srclib
    sudo cp -r apr ~/httpd-2.4.3/srclib
cd
download pcre-8.31.tar.gz from http://sourceforge.net/projects/pcre/files/pcre/8.31/
    Please note that pcre-8.31 isn't obtainable through the wget but needs to be done     manually through sourceforge.
tar -xzvf pcre-8.31.tar.gz && cd pcre-8.31
sudo ./configure
sudo make
sudo make install
cd
cd httpd-2.4.3
sudo ./configure --prefix=/usr/local/apache2 --enable-mods-shared=all     --enable-deflate --enable-proxy --enable-proxy-balancer --enable-proxy-http --with-mpm=prefork --with-included-apr --with-included-apr-util
sudo make
sudo make install

After this process. I no longer get an error in installation. However, I think I'm missing a step because it's not found in /etc/apache2 and if I use a command that uses apache the terminal tells me it's not installed.  Can anyone tell me what I'm missing after make install.
Thanks in advance for any help you have to offer!
Answer: Most likely you have another libapr somewhere on your system. First I uninstalled libapr that came with the system, which caused a compile error.
Then I cleaned up everything except the source I found via
locate apr

Another make clean and make install fixed my problem


What are advantages & disadvantages of using a Peer-to-Peer lending site or network?

Question: If I was looking to consolidate some credit card debt and wanted to use a peer to peer lending service, what things do I need to look out for?
Comment: Wow - I've never heard of a Peer-to-Peer lending site!  Very interested in this answer.
Comment: The top 3 reported in a google search are prosper.com, lendingclub.com, and peer-lend.com.
Comment: Similar but not duplicate http://money.stackexchange.com/q/1641/3361
Comment: that is actually the duplicate of this, this question was asked first
Comment: @JeffMartin So I see, but I'm not sure what to do, as that later question was made a community wiki. I'll try looking around on meta. Thanks for mentioning it though, as I needed some motivation ;#)
Answer: Main advantages

you are closer to your lenders, not some impersonal bank
you are more likely to get a favorable rate
more flexible terms

Main disadvantages

You are closer to your lenders(see advantages), it is not as bad as
borrowing money from your friends or relatives, but the personal
factor can come into play(even though p2p lending sites serve as a
bit of buffer).
You need to be aware on how the lending sites get paid and how much.
Obviously you should not have to pay anything in advance to originate
a loan(those are generally scams).
Finally a very subjective opinion, but I think in terms of financial
returns p2p lending is not that great for lenders, but good for
borrowers, precisely, because individual lenders are not that great
at determining credit risk of borrowers.

In any case it should not concern you too much, as long as you can get your loan.
Comment: some links to p-to-p lender would inprove this answer
Comment: I agree with mr. google there.  Some links to different sites and ways they mitigate risk to lenders would be nice to know.
Comment: +1 for articulating that the risk/reward is better for the borrowers than the lenders.
Answer: Prosper and Lending-Club are the two main sites for this. I was on Prosper for a while.
To get a credit card consolidation at a good rate, you need a good credit score and you need a good narrative.  You will be putting together what is basically a presentation to strangers on why you need the loan and that you are perfectly capable of paying it back. The second part is important. You will want to state your income and your job stability to show that you will be able to pay this loan off over the 3 year life of it.


Can two Cloud of Daggers be cast in the same area by different spell casters?

Question: Quick overview of the situation, the party is 3rd level and the warlock and the bard can now both cast cloud of daggers. We were in a lizardfolk den and they saw us and came running down a 5-foot corridor. The bard was first in initiative and threw out the cloud of daggers right on them. The warlock went next and wanted to do the same. Is there any ruling against this? The lizardfolk were next and would take the 4d4 from the bard at the start of their turn. Would they also take the warlock's 4d4 (A grand total of 8d4), or do these effects need to be staggered?
Comment: Related (overlapping AOEs): "[Does the Spirit Guardians spell stack with multiple casters?](https://rpg.stackexchange.com/questions/93074)" also this question on simultaneous *instantaneous* spells/effects: "[When a creature is hit with more than one fireball simultaneously, do they take damage from all of them?](https://rpg.stackexchange.com/questions/128318)"
Comment: I imagine that the sound would be awful as dozens of daggers whirl asynchronously against each other.
Answer: It depends on whether you believe damage to be an effect of a spell, and whether you believe the cloud of daggers castings have any sort of overlapping "duration"; personally, only one instance of damage
There is the following rule from the "Combining Magical Effects" section:

The effects of the same spell cast multiple times don't combine, however. Instead, the most potent effect - such as the highest bonus - from those castings applies while their durations overlap.
- Player's Handbook (page 205)

There is also the following optional (as every rule there is optional) rule from the "Simultaneous Effects" section of Xanathar's Guide to Everything:

If two or more things happen at the same time on a character or monster's turn, the person at the game table — whether player or DM — who controls that creature decides the order in which those things happen. For example, if two effects occur at the end of a player character's turn, the player decides which of the two effects happens first.
- Xanathar's Guide to Everything (page 77)

There are a few things that need to be determined here; firstly, whether or not damage is even an effect of a spell. One could argue that it is not (and people have done so here), in which case it does not apply to the above rule and the creature will take both instances of damage. That said, I personally believe that the spell causes the damage and therefore the damage is an effect of the spell.
There is also the question of whether the spells actually have an overlapping duration at all. The castings do have their own durations and those are counting down at the same time (overlapping). Thus the spells are overlapping and any effects they might cause must all come from only one of the castings; the creature only takes damage once.
Alternatively, you could say that the rule on overlapping effects applies to each effect separately and not to the spells as a whole; thus the damages never overlap (using Xanathar's) and both would apply fully. But this would likely be incorrect and goes against the current answer to the question "How do you choose active effects when two instances of the same spell/feature overlap?".
I personally believe that damage is an effect of a spell and that the castings are overlapping, thus the creature will only take 4d4 damage, but there is space and reasoning to argue otherwise.
An oddity from having only one instance of damage apply
Spacing apart the castings by a mere 5 feet causes radically different behavior; the creature would take damage when starting its turn and also when entering the second AoE.
If a medium creature walked into one AoE and then the other they would take the damage twice, not just once. However, a large (or larger) creature could potentially walk into both AoEs simultaneously, resulting in them only taking damage once.
Comment: Why would it matter if the effects were spaced apart? There's no qualifier that says effects only don't stack when they are on the same spot.  Note also that when either spell expires their durations no longer apply, and the full both spells damage would then apply, and also that not stacking doesn't mean 4d4 damage, it means the better of 4d4 damage rolled twice (at least, while the durations overlap).
Comment: @Pleasestopbeingevil Sorry I don't understand some of what you've said. If you are hit by two *firebolts* at different times, you take damage from both. If you walk into one *cloud of daggers* and **then** the other, you take damage from both. And what do you mean "the full damage from both would apply when one spell *ends*?" Also what do you mean they would take 4d4 twice? This sounds like a completely different answer moreso than a comment. The stacking rule does not make the more potent effects happen *multiple times*
Comment: If it did then a level 1 casting and a level 9 casting would result in effectively 2 level 9 castings. I think you're saying it's like advantage but for damage. I do not believe this is, at all, covered in the overlapping effect rule and if you feel that is the case I suggest you open a question on it
Comment: @Medix2, in a pure English sense damage is of course an effect of the spell. However, I believe _effect_ here is a synonym for _condition_. Not the save DC, not the damage, only the lasting things.
Comment: @András Exactly why I've said that it depends whether you consider damage an effect at all. Though the rules do say that DoTs do not stack, though DoTs are more like conditions: "For example, if a target is ignited by a fire elemental's Fire Form trait, the ongoing fire damage doesn't increase if the burning target is subjected to that trait again."
Answer: The lizardfolk would only take 4d4
Borrowing heavily from this answer, multiple of the same spell never stack. From the Player's Handbook, "Combining Magical Effects":

The effects of different spells add together while the durations of those spells overlap. The effects of the same spell cast multiple times don't combine, however. Instead, the most potent effect — such as the highest bonus — from those castings applies while their durations overlap.

RAW, the bard and the warlock would not get more damage out of their cloud of dagger spells by overlapping them.
To narratively justify this RAW, think of it as the damage coming from the fact that the area is filled with daggers, and adding more daggers doesn't change the fact that the area is filled with daggers.
Of course, if as a DM, this seems unrealistic, you could always overrule RAW and claim that both spells do take effect, since there are now twice as many daggers filling that area.
Comment: @Medix2 It did re-read my other answer before posting this one. I think my take on "effect" in the context of _fireball_ was hinged on the fact that a _fireball_ is instantaneous, whereas _cloud of daggers_ is not.
Comment: Ah that makes a lot of sense, just wondering what you thought about it. Thank you!
Comment: I feel like the rule can be justified from a narrative perspective if you think of magic as ends-oriented rather than like a physical effect. If a computer program contains a line to the effect of "write 8 into memory adress 40" and another line does say the same the two are not added - you just get the end result of 8 in adress 40. Similarly a magic spell that fills a certain volume of space with a certain amount of daggers will leave that space with that amount of daggers - regardless of how many such daggers where there before.
Comment: Does this contradict your answer [here](https://rpg.stackexchange.com/a/128320/36521) stating "I would argue that the damage dealt from the fireball is not an "effect""


EE 2 and Transcribe - Get related entry ids

Question: EE 2.9.3
Transcribe 1.6.2
I have an older EE site where I need to output the entry_id of the associated translated entry.
Something like this:
on the English listing page:
English title
English Summary
  - French Entry ID

And then on the French page this:
French Title
French Summary
  - English Entry ID

Is this possible? If so how? Maybe through a database query? Not sure how to do that either. FWIW I can't upgrade to the latest EE or transcribe.
Looking in the database I see a table exp_transcribe_entries_languages with a column of relationship_id that contains a hash which is duplicated on associated entries. other columns are id, language_id, and entry_id
So two entries that are related to each other include:
id    language_id   entry_id  relationship_id
1372      1           1372     5bf41ee76f1ef
1376      2           1376     5bf41ee76f1ef

You can see the relationship_id matches. Is there a database query that I could put in a template so that I can output the entry id of the opposite language. Where langauge_id of 1 = english and 2 = french
something like this:
{exp:channel:entries channel="news" limit="5" disable="member_data|comments"}

{title}

Current Language Entry ID: {entry_id}

Other Language Entry ID: db_query_here

{/exp:channel:entries}

Thank you.
Answer: looks like you could use this according to the docs:
{exp:transcribe:language_links has_entry="yes"}{languages}{rel:entry_id}{/languages}{/exp:transcribe:language_links}


Are there any ready cloud services or frameworks for firmware update over the air?

Question: I have prototype of the resource constrained-device (8-bit MCU with no-OS firmware), interacting with a web server. I wonder are there any solutions, frameworks or cloud services for updating my device firmware from the web. From my research there is Microsoft IoT Hub, but I am afraid it does not suits for such resource-constrained devices. There is one more solution, I found - mbed Cloud portal, but I am not sure how it works. Can anyone help me via any advice, maybe there are some best practices for implementing firmware upgrade over the air for embedded devices in secure and robust way?
Comment: There are no such services atleast as of now. Implementing one in general is very tedious, service targeting specific device type can implemented.
Comment: There is https://mender.io/, which is aproximately what you want. But I believe, it is target towards "high end" embedded devices and for 8-bit nodes.
Answer: mbed cloud does offer full firmware update functionality, but I think you'd have trouble porting it to your platform if you're running without an OS. I don't think the source is open today, so you can't even use it for reference. I'm also not sure what the criteria are for getting access right now.
You need to think about the features you need - is this a large scale deployment where you need to be able to do staged firmware roll-outs, do you care about signing the firmware, or is your platform completely open to anyone with physical access? How much do you care about being able to recover a bricked device without JTAG?
Realistically, features like OTA updates are probably something that drive your OS and device selection - once you factor in development costs.
Answer: Check out OTA which is abbreviation of Over The Air. Arduino has that property.
You can make update with Arduino IDE, Web Browser or HTTP Server.

Arduino IDE option is intended primarily for software development phase. The two other options would be more useful after deployment, to provide module with application updates manually with a web browser or automatically using a http server.
Comment: One of the most unpleasant things about that library and Arduino in general is lack of security. This solution is suitable for DIY or school projects, but not for commercial devices. Particular thing I dont like is absence of any authentication: it is unprotected from replacing firmware with malicious one, having correct MD5 digest.
Answer: You might take a look at Particle (IoT). I'm not sure they support Arduino, but they do offer some cheap embedded boards themselves.
Answer: I'll be answering only this part, as I know of no 'out of the box' system for an unknown firwmare.

maybe there are some best practices for implementing firmware upgrade
  over the air for embedded devices in secure and robust way?

In term of practice, what I would do is as follow:
1) Have a very minimal boot loader, something as dumb as possible only responsible to load the firmware with the following constraints:

Ability to record last boot success/failure (to rollback to a working version in case of failure)
Some kind of emergency process to accept a new firmware in case of catastrophic failure (optional, could be avoided if a "bricked" device is allowable)

2) Set your storage to have two "boot banks" of reasonable size to handle future evolution and firmware growth.
3) Checksum the firmware image after download to ensure it is correct before burning, checksum the bank of destination after burning to again ensure it won't fail booting for a missing bit somewhere.
The overlooked point is usually the checksum of the downloaded image before and after burning, resulting in corrupted system written on the device. Using two banks and alternating usually ease the update process.
Answer: One more interesting platform, I discovered is DeviceDrive. Here is the video explaining how things work. Their OTA system seems to be pretty flexible.


What are the Three Trainings and how are they practical?

Question: What are the Three Trainings and how are they practical?
Specifically how does one practice them?
Answer: The threefold training (Pali: sikkha) consists of: morality (sila); concentration (samadhi); and wisdom (panna).
Sikkha is meant to conquer and eradicate the defilements (kilesas).
Visuddhimagga XXII,49

'The defilements are the ten states, namely: greed; hate; delusion;
  conceit; false view; uncertainty; stiffness of mind; agitation;
  conciencelessness, shamelessness. They are so called because they are
  themselves defiled and because they defile their associated states.'

Each of those defilements has 3 stages (bhumi) which are identical to the 3 stages of consciousness (latent - manifested - action).

the latent stage = anusaya-bhumi
the manifest stage = pariyutthana-bhumi
the action stage = vitikkama-bhumi

Through the threefold training, it is possible to conquer and eradicate these defilements in the 3 subsequent stages: sila-sikkha; samadhi-sikkha; and panna-sikkha.
The training itself is a strict personal affair: Purity and impurity depend on oneself. No one can purify another (Dhammapada).
Answer: The Three (Higher) Trainings are:
Ethics
Concentration
Wisdom
The practice of ETHICS entails abandoning negative actions of body, speech and mind (such as killing, stealing, lying, sexual misconduct, intoxicating the body, harmful speech, greed, etc). And cultivating virtuous actions of body, speech and mind (generosity, patience, gentle speech, etc).
The practice of CONCENTRATION entails developing single-pointed attention on a meditative object (such as the sensations of the breath, a mental image, thoughts and the space of the mind, etc) by cultivating relaxation, stability and vividness. There are 9 stages for the this practice (shamatha) and the culmination is a refined mind that experiences bliss, clarity and non-conceptuality. At this point you are able to focus your attention effortless for long periods (4 hours or more) without any distraction or internal chit-chat, this state is called samadhi.
The practice of WISDOM entails, gaining insight into the nature of reality, this means understanding experientially and not only conceptually how all phenomena and oneself exist. Everything exists as an interdependent matrix of causes and effects, and everything is empty of inherent existence.
The first step is to begin practicing the Four Applications of Mindfulness:
Applied Mindfulness to the body, feelings, mental events and phenomena. These practices imply not only being mindful of the body sensations, thoughts, etc, but also to develop wisdom by questioning if these things exist as we perceive them or if they are impermanent, interdependent and lacking an inherent, real, solid existence. After becoming good at these practices you can also practice analytical meditation, debate, and Dream yoga to start questioning the solidity of what you call reality.These practices are called Vipashyana and one applies them also to the I, until one finds that one doesn't exist as an independent ego, but as a matrix of interrelated phenomena and that we also lack inherent existence. There's a risk here to think we don't exist at all and becoming depressed or nihilistic, so it's important to practice also Dzogchen, Mahamudra or similar practice to understand and realize that we are pure awareness and by recognizing this primordial consciousness we transcend the concepts of existence and non-existence and we become enlightened.
This insights can only be sustained if you have achieved single-pointed concentration (shamatha) first, otherwise with an unbalanced, wandering mind trying to develop wisdom is not possible. And concentration can only be achieved if one lives an ethical way of life, because a mind that is filled with mental afflictions such as anger, craving, greed, attachment, ignorance, arrogance, etc, is a wandering mind unable to find peace and develop concentration, furthermore an afflictive mind is ignorant and unable to develop wisdom.
Answer: The Three Trainings in Buddhism are the most important, organizing feature in Buddhism.
Everything that is not related to the 2nd and 3rd training is called the 1st training: morality.
This is related to learning to live life correctly, having Right Livelihood, developing communication skills with others, forgiving others, thinking about how to enjoy time with friends, choosing friends, etc.
Basically, success in the 1st training means doing good in the world, for ourselves and others.
The best way to understand what the 1st training is, is to understand the 2nd and 3rd trainings and understand that the 1st training is what the 2nd and 3rd training is not. These latter two trainings have a much simpler definitions and are also very important in spiritual growth because they are very much in our locus-of-control.
The 2nd training is concentration.
This training involves any meditation practice which makes one calmer, more blissful and directed towards the five qualities of jhana.
The success in this training contains mastery of the entire range of form and formless jhanas.
The 3rd training is wisdom.
This training is synonymous with vipassana and involves any meditation practice which trains one in becoming more present and noticing of the 3 Characteristics.
The success in this training contains mastery of the Stages of Insight, which has a continuous and recursive process to it and blossoms in Awakening/Fruition.
Since the 2nd and 3rd training deal with samatha and vipassana meditation respectively, the 1st training, as mentioned earlier, deals with the good work we do in the rest of our lives.
This is a wonderful organizing structure because of the fact that most of what we do in our daily lives falls into the 1st training and this type of understanding can help us prioritize. For example, participating on SE Buddhism, conversing with online forums, and participating in a local Sangha is the 1st training and we should continue to do so... but we should neglect our Practice, namely the 2nd and 3rd training.
The Three Trainings are also mutually supportive of each other and improving in any training is definitely going to cause an improvement in the other trainings so they should all be worked on simultaneously. This mutual support raises more interest questions like what category does brahma meditation would fall under? and why does vipassana sometimes seem like jhana?
It's not the point to categorize everything into this system. What's important is that one not be too involved in the 1st training and realize that the training in concentration and wisdom are very important in Buddhism and lead directly to the goal of Buddhism.
Also these two trainings take a lot of time (e.g. 3 year meditation retreats).
For more info on this idea see "Mastering the Core Teachings of the Buddha."


Typical Stock Boost Values

Question: For an engine that is boosted out of the factory, what are typical maximum and average boost values? Are they conservative in the 5-6 PSI range or do they get more aggressive getting up to 10-15 PSI? I'm more interested in what OEMs are doing with undersized engines to make them driveable versus more sporty performance enhancements.
Answer: This question doesn't provide enough information for us to answer it well as originally written.  Some of the important factors determining what boost level is used include:

Base compression rate of the engine (see this question for related discussion).
Octane of the fuel to reduce the risk of detonation (see point 1).
The temperature and humidity of the ambient air.
The temperature of the air after it passes through the intake path.
The application and related requirements such as reliability and longevity (a race car does not live as long between rebuilds as my daily driver).

A more specific question would help us address your particular points of interest.  Which vehicle are you interested in?  Are you thinking of upping the boost?  What application to you plan to put this vehicle to?
I find Corky Bell's book to be an excellent (and entertaining) reference for background information on all of the above.
Comment: I've added some detail to my original post to address some of your questions
Answer: There's a wide variation, but back in the '90's it was clustered in the 10-12psi range for a typical 4-cyl turbocharged performance model.  Nowadays 16-18psi is not abnormal for high performance factory cars.  Of course, you'll find some economy cars in the 5-6psi range, where they're using boost to let a little tiny fuel-efficient engine not be completely miserable to drive.  :-)
Comment: For addingg a turbo to a factory NA engine, yes.  5-6psi is typical for those applications.  However, factory turbo engines back in the early Integra days normally came with ~8:1 compression (7.8 was a particularly popular value) and hence supported the 10-12psi just fine.  Lately that's been jumping up to 8.5:1-9:1 in factory turbo setups along with higher boost as engine design and controls have gotten better.
Comment: Actually, back in the days when I was considering boosting my Integra, 1/2 bar (7 psi) was considered to be quite high boost considering the 10:1 compression ratio.
Answer: Bob Cross's answer.
And those are just the factors that are easy to quantify! There's also the combustion chambers' individual propensity to knock determined by geometry with spooky attributes like squish, tumble and swirl to consider. Then there is cycle to cycle variability and the effect of carbon deposits over the life of the engine, which will be different for each individual engine, let alone different models. I think reading any of engineering literature on knock would dissuade anyone from trying to give numbers for such an open ended question, even if a displacement and compression ratio was specified. It's much more complicated than not exceeding a temperature threshold.
I think reading something like Heywood's chapter on "Combustion in Spark Ignition Engines" gives a lot of insight into these factors. I'm assuming, of course, that you want the deeper insight.
Comment: I've looked through the mentioned section in Heywood, and even read a good portion of the section on knock. I'm not looking for any more insight than that, i'd just like to know broadly what range or pressures engines are boosted to. Is 15 psi an upper limit, and is that usually reserved for performance vehicles? Or are greater boost values common?
Comment: Fair enough. I think your best option is to compile a list of vehicles that fit your undersized engine category and see how much boost they run. Or even better find someone with experience equivalent to that survey. Unfortunately, that person isn't me.
Comment: @wesanyer Actually, can you give a couple of examples in that category of cars? I'm at a loss to think of any. Probably because I find ~1.3litre N/A engines with variable valve timing to be very drivable, although I'll admit that sporty driving often requires double-clutching/heel-toe into first. I blame the engineers for trying to stop people from accidentally selecting first.
Comment: That's the thing, I don't know any particular car models to reference. I do know from speaking to some Ford and GM engineers that both these OEMs are moving _towards_ undersized vehicles with boosting, in order to meet tougher CAFE standards. I don't know of any that are currently on the market though. Are most stock boosted motors strictly boosted for performance?
Answer: 2016 Opel Astra, 4cyl 1.4 Turbo 125HP/92KW - According to the ECU goes to 5PSI
2018 Seat Leon ST, 4cyl 1.4 turbo 150HP/110KW - According to the ECU goes to 18PSI

Typical Stock Boost Values


The off button eliminated in the right corner of above in ubuntu 12.04 (Unity)

Question: I always have used unity and I have never had any problem, but now that I reinstated ubuntu 12.04, but when it had stopped using her on having extinguished it I saw that unity's off button was not, it is possible to extinguish of other forms like that that I her restarted to see if it was corrected but till now I continue with the same problem, some programs that I installed were ubuntu tweak and the interior decorator of windows emerald, not if the problem is for one of these things. How can I solve it?
Answer: Try this:
Hit Alt+Ctrl+T to open terminal and run following commands:

sudo apt-get purge indicator-session
sudo apt-get install indicator-session

And then restart you system!
Answer: There is a bug where if you use a theme other than Ambiance or Radiance, the system status menu in the top right won't show.
I believe it is fixed if you install gnome-icon-theme-full. Log out and then log back in.
If that doesn't work, I recommend you stick with Ambiance or Radiance.


How can I train my cat to not jump on the kitchen counters?

Question: My cat jumps onto our kitchen counters frequently, sometimes causing major accidents. What is the best way to break that habit? Would I need one of those electric shocker things?
Comment: I guess I've been lucky; I've always found that some combination of the squirt bottle and a barked "hey!" or "no!" eventually does the job as long as I'm completely consistent about which surfaces are Not For Kitty. Or at least it convinces them to be very careful not to be caught, which is good enough for me.
Answer: One option for "punishing" cats that works with some of them is to get a water spray bottle. You then spray them with it when they jump up on something you don't want them on.
Please be sure to use a bottle that is just for water and never had any chemicals in it (could be harmful to them since it could get into their eyes and cats lick themselves a lot)
Comment: I use a spray bottle but they just jump back up as soon as I leave the room (and jump down when I re-enter the room).
Answer: Two methods that I have found my cats respond to quite well:

Some sort of loud noise:

Clapping your hands
Snapping your fingers (if you can do it loud enough)

Placing some tin foil on the counter. I would make strips of foil and bend them in the middle so that they stand up (something like this) and place them on the edges of the counter. I placed them like that so that it was possible to see the reflective foil even from the cat's eye level.
I noticed that my cats didn't really like the sound or the touch of the foil so they learned pretty fast that up there lies the noisy shiny stuff monster. After ~1 week I didn't have to set out the foil any more.

The first option is a pretty much generic method that I use for any sort of bad behavior and is really only an option when I'm around. If you do catch the feline in-the-act of jumping up, your reaction should be immediate and consistent. If you have more people living with this cat, make sure you are all enforcing the same boundaries.
The tin foil however is great for when you're not at home. If you come back, and the foil is in exactly the same place, you'll know that the cat hasn't been up there.
Oh and please, no "electric shocker thing"
Comment: Yes! We also used twisted-up blue painter's tape with ours. She learned quick.
Comment: My cats think tin-foil is a toy, but I had success using empty 2L pop bottles. Just lined them up on the edge of the counter and she hasn't been up there since scaring herself a few times by knocking them all down. I don't like your first option because then the cat associates being reprimanded for getting on the counter with you, so just does it when you're not around :)
Comment: @AndrewBarber Haha, that would work ;)
Comment: @Rachel - When I answered this post, my cats were really kittens (just a few months old). I guess the "noise" that the foil made was enough for them. Your empty cans is pretty much the same idea - something that triggers a startling noise. It's worked great for us - just a few months later and the monsters are no longer counter surfing... Either that or we're just not seeing them do it :P
Answer: Also, since you're not going to be in the kitchen all the time, you could consider getting one of the movement-activated hissing cans (sorry, I'm not at home and can't look up the brand information). That way, you can avoid the cat thinking that the only time it needs to avoid the counters is when you're there.
The cans are about the size of a soda can, with a motion sensor that will trigger and spray a jet of air that makes a hissing noise when it detects anything (It works. Startles the heck out of you if you set it off accidentally).
One caveat - try not to laugh at the cat when it gets startled by the hissing can. They don't like that.
Answer: Kyle is right, Negative reinforcement is probably the best solution to a problem like this, since you cant really reward them for not going on the counter and expect them to understand. If your finding it hard to always keep a spray bottle near the counter cats usually respond to yelling as well
also make sure your cats are'nt doing it because they know it gets your attention, check their food and water after each time, and make sure to pet them regurlarly
Comment: What Kyle describes is punishment, not negative reinforcement. Negative reinforcement is removing a noxious stimulus to reward correct behavior.
Comment: yes and a hissing sound. I flick water from my fingers if I'm at the sink
Answer: Never use a spray bottle...all that does is make your cat afraid of you!
According to behaviorist Pam Johnson Bennett,

The squirt bottle technique only accomplishes three things:

It creates frustration in the cat
It causes the cat to become afraid of you
The cat learns to wait until you aren't around before engaging in the behavior

Additionally, behaviorist Jackson Galaxy (of the television show My Cat From Hell) states:

What is the cat actually learning in this scenario? Is he learning
  that the counter is a bad place to be be? No. What Tigger is learning
  is that, first, the counter is a bad place to be when you are present
  and holding the squirt bottle, and second, he is learning to be afraid
  of you. The bottle appears to him as an extension of your arm, and it
  is you, not the bottle, that is getting him wet.

Other training techniques can be found in the question:
How should I discipline my cat for bad behavior?
Comment: Not true in my experience.
Comment: Actually, I've known one cat who decided he _liked_ being squirted, and deliberately provoked until the humans caught on and stopped rewarding him. I can certainly imagine that _some_ cats might be scared by the squirt bottle, especially if it makes a hissing sound, but the more common reaction I've seen is startlement and mild distaste. Popular behaviorists tend to overgeneralize their own experience and overestimate their knowledge. That isn't to say that they might not have good ideas for alternatives, though
Comment: Agree. The squirt bottle is a game...how much can I get away with before my owner tries to squirt me...and I bet I can run away before I get squirted.  You are unknowingly giving kitty your attention (positive reinforcement).  Remember:  Negative attention is still attention.
Answer: If saying no in a stern voice and picking them up and putting them down doesn't work, then try putting tin foil on your counter tops. The noise will scare them and eventually they won't even want to attempt it anymore. Whatever you do, don't spray them. It's cruel and cats don't understand why you're doing it.


gvim profile for perl programming

Question: can you get some good easy gvim profile file for perl programming ?
Comment: Should be on SO.
Answer: There's a Perl IDE extension called perl-support.vim available on vim.org.  See the documentation and hotkey map (PDF).  It seems built for gvim or other vim-in-desktop-environments, though.  (Oh, and Manni hates it.)
The SO question Manni links to is actually pretty extensive -- the questioner added the good suggestions into the question body.  It includes a lot of other Perl-related vim plugins and <code>.vimrc</code> tweaks.
Answer: Check the answers to this question over on stackoverflow.com: What are your suggestions for an ideal Vim configuration for Perl development?

gvim profile for perl programming


How long can you give job talks on your thesis-book project?

Question: I'm two years out of my PhD in the humanities and have given a couple of job talks since, all on material from my dissertation.  Not only have I spent months trying to make the talks themselves as good as possible, they're based on ideas and material I've had the entirety of my PhD to feel confident about presenting.  My question is: at what point on the market do universities expect you to present new material that's not part of your dissertation research?  I'm at the very early stages of developing my "second book project," but my research / argument aren't nearly as developed!
Answer: I'm in a vastly different field, but if your work is progressing at approximately the same rate as your community's then I wouldn't worry about it.
Perhaps you can talk about your ongoing work as well just to signal that you're not stagnant. The point of the job talk is to assure the department that you're going to do good work while there!
Answer: Most universities want to see that you are at the publication curve or ahead of it. For example, its perfectly ok to talk about your dissertation three years out of grad school if you are talking with your now published results. If, on the other hand, you are discussing a phd that you never turned into a publication, that can be a little trickier. If you are currently in the revision process of the publication, thats probably ok too.
The main point that I am getting at is that talking about your dissertation is ok, its likely the foundation of your future research. Its even better, though, if you are discussing the published results from your dissertation in a journal or in your case, your published monograph.
Answer: I do not know how it in humanities, but in general the idea is that in job-talk you present the solid work that you have already done and preferably published. Put it simple: you should present the most solid work that you have done because it is the track-record that you are judged. The talk can include some portion of newer work, but as soon as it is not published it is better to be only small part. In job-talks there is a common practice to devote 5-10 last minutes to future directions. Your new part can go for example there.
Answer: If you are already in a tenure track position, you should start talking about new work now.  Maybe make it a blend if you just don't have much.  But certainly I would not emphasize earlier work just because you have a more polished talk.
If you are still looking for a good position (out of work, or doing post docs or lecture positions) than it is fine and maybe even preferable to concentrate on the thesis.  But even here I would emphasize some of your recent work.
Remember these talks are not just talks on the content and for enjoyment but advertisements of you.  Yes, make them pleasant and revealing, sure.  But make yourself look good.
Answer: For as long as the material is relevant.


Why is there "the" in "oh the horror"?

Question: I am wondering about the interjection "oh, the horror!". If it should be treated as an interjection directed to "horror" (there are similar expressions in other languages), why does it use the article "the"? There is no article in "Oh Lord!" or "Oh Brother, Where Art Thou?", so why in "Oh the horror"?
Answer: I always took it to be one of those phrases that represents a partial utterance, as in "Oh, the horror that this invokes...". You are not addressing "horror" directly or evocatively; it's not a name or a title. I get the same impression from the famous "Oh, the humanity" quote.
By comparison, if we say "Oh, Brother" or "Oh, Lord", that would be more in an evocative sense of a prayer ("Oh, Lord, give me strength...") in which case an article would just be senseless.
Questor
Answer:
There is no article in "Oh Lord!"

"Oh Lord!" is what's called vocative and it should probably be spelled as O not Oh ("O Lord!").
When used in the phrase "oh, the horror!" it's an interjection.
Note that there's a comma of difference too: it's not "Oh, Lord!" and not "oh the horror!"
Answer: I think it is difficult to compare "Oh Lord" or "Oh Brother" with "Oh the horror". The "horror" is not a person, it describes a state.
The interjection in "Oh the horror" gives the phrase a equivalent meaning to "Oh what a horror".
Comment: I agree with you that we are not addressing or invoking **horror**, and that is the reason for the article. However, we need not only address beings. *O Death, where is thy sting?* or *O Beauty, Passing Beauty!*.

Why is there "the" in "oh the horror"?


Client denied by server configuration with tomcat

Question: I have found at least a dozen entries for this error even in this forum, and many outside. All are basically saying that inside <Directory></Directory>, I have "deny all" directive, and no "allow" directive.
I cannot write a fixed directory to match because it is created on the fly by a backend tomcat server.
When I entered "myUrl/test/request/user1/1234567890/download", I get

403 Forbidden: You don't have permission to access /test/request/user1/1234567890/download.

httpd error log shows:
[error] [client xxx.xx.xx.xxx] client denied by server configuration: /data/test, referer: myUrl/test/request/user1/1234567890

The part beginning with "test" is created by the backend tomcat, in which "user1" and "1234567890" vary, while the other parts of the directory structure remain fixed.
In my httpd.conf, I do have:
<VirtualHost *:80>
    DocumentRoot /data
    ---
    ---
    RewriteRule ^/test - [L]
    ---
</VirtualHost>

How do I solve this? Even if  I create a different  and create another document root, I will need a regex. Somewhere outside , I tried this:
<Directory "/data/test/request/*/*/download">
    Options -Indexes -FollowSymLinks
    AllowOverride None
    Order allow,deny
    Allow from all
</Directory>

But no success.
I am using "ajp" to talk to backend tomcat and have necessary module in place and I can telnet the backend tomcat server (on 8009) . So it should not be ajp communications problem.
The "test" piece in above url is actually a "context" inside /webapps directory of tomcat. Owner in that "test" context is tomcat, but I have added read permission for everyone.
Answer: First, I had to "deny all" for "/"
Directory
    Deny from all
/Directory

Only then "Allow for all" for "/data"
Directory /data
    ---
    ---
    Allow from all
/Directory

Then I rearranged RewriteRule, Redirect, ProxyPass, ProxyPassReverse inside the
VirtualHost *:80
/VirtualHost

and it worked!


Hydrangea leaves going brown

Question: We just recently bought and installed a hydrangea about a month ago. We planted it and added organic fertilizer and have been watering it daily. It gets morning and mid day sun and shade in the afternoon. It is starting to brown on its leaves. What is causing this and how do we prevent it?
Answer: Two possibilities - Hydrangeas of this type prefer to be out of the midday sun, especially if the uv levels where you live are high - morning and evening, or dappled sun is fine. Second, you say you're watering daily, but that doesn't necessarily mean the root ball of the plant is getting enough water. You don't say how you're watering and how long for, but if your weather is warm and sunny (and even more so if its windy) this plant will need about a gallon of water per day until its been able to extend its roots into the soil to seek out its own supplies, which takes some time - up to Fall easily. If the weather is cool and not sunny, then about a gallon or two every 3 or 4 days should suffice.
So essentially, it depends what you're watering with and how long for...as well as whether its baking in hot sun in the middle of the day.

Hydrangea leaves going brown


Does a screensaver save the computer display screen?

Question: Does a screensaver save the computer display screen?
And if it does, what does it save the screen from?
If the above two questions have a NO answer, than why is it called screensaver?
Comment: It did on old CRT monitors (where a frozen screen could become imprinted on the monitor), but I don't think that's the case for LCD monitors.
Comment: As Avi said, on old (very old, think 15-20 years) screens they're prevent burn in. On anything moderately modern, they're just pretty pictures. The only benefit is that they help provide some security by blanking any sensitive documents on screen and usually requiring a password to terminate.
Comment: http://www.techlore.com/article/10099/Do-LCD-TVs-Burn-In-/
Comment: Also see, [What is the usefulness of a screensaver on a computer using a LCD monitor?](http://superuser.com/q/480793/263)
Comment: Any of those could be answers.
Comment: wiki answer: http://en.wikipedia.org/wiki/Screen_burn-in
Comment: and [superusers.SE agree with wikipedia](http://superuser.com/questions/3290/is-there-a-real-reason-to-use-a-screen-saver)
Answer: This is a summary of Wikipedia:Screen burn-in.
CRT, Plasma, and OLED displays
These displays develop burn-in due to degradation of the light emitting compounds. Screensavers were initially designed to prevent phosphor burn-in in cathode ray tube (CRT) monitors. Plasma displays are also susceptible to burn-in due to overheating of the phosphors. Organic light-emitting diode (OLED) displays develop burn-in due to degradation of the organic compounds. (cnet)
In the worst cases, the burn-in is visible even when the display is not powered:

LCDs
Liquid crystal displays (LCDs) can suffer a different type of burn-in (gizmodo) also referred to as image persistence (fujitsu). Liquid crystals are designed to allow light through in their relaxed state, but can become "stuck" at a particular level of activation, causing an effect that looks very similar to traditional burn-in. (ref)

Screensavers
Screensavers can be useful in preventing burn-in on CRT, plasma, and OLED displays. For LCD displays, image persitence can be prevented by using a screensaver. (fujitsu)
Comment: A moving screensaver prevents burn-in by not having the same pixels lit continuously, but makes it easy to tell that the screen is turned on. A "black" screensaver might make you accidentally power cycle when you come up to a computer and think it's turned off.
Comment: Does a moving screensaver have *any* advantage over simply making the screen dark?
Comment: I understand the mechanism on LCD and OLED (light emitting chemical will "wear out" via photochemical side reactions. But what is the mechanism on LCDs? Is there any evidence of a real effect at all?
Comment: @gerrit Not that I can tell.
Comment: @matt_black I attached an image of an LCD suffering image persistence, but I can add referenced details about the mechanism. Thanks.


jpg vs jpeg images?

Question: jpeg files dont open or display like jpg files, are they the same?  I noticed that when I rename jpeg top jpg it is able to open, I am not sure if it is the cross platform from Mac to PC or if it has something to do with digital camera format.
Comment: Google them and read their Wikipedia pages. I think they are one and the same.
Answer: Internally, you'll find that a jpeg file and a jpg file are one and the same. Both file types have a header that includes JFIF to identify the type of file.
You don't specify which OS you're using that has this problem, but if it is a Windows machine, your defaults are set in such a way as to have no application assigned with which to open the jpeg file type.
The specific steps are dependent on the version of the operating system. The steps involved for Windows 10 are very different from those for Windows 7, but can easily be located using the search terms "set default applications windows X" and finding a tutorial which appeals to you.
You can also right click on the filename and use "open with" then select the entry "use default program" from the context menu.
Answer: I figured it was a operating system difference, I have jpeg files associated with photoshop and they open fine, just when I use them in my slideshow program in the file list view, those jpegs have extra unidentified characters at the end of the file name, not to mention they dont show. I have to go back and rename them to .jpg to make them show and then the actual name is corrected with out me renaming the full name of the file just the extension.
Comment: Or you can just instruct the os to pair the extension with a different software.

jpg vs jpeg images?


Network issues in Windows 7

Question: We recently upgraded a dozen of PCs to new hardware and Windows 7 professional (before we had XP), but we are experiencing many newtwork issues, for example SSH sessions (using Putty) stops working after a while.
Checking the LAN with various testing tools doesn't report any issue.
We have no XP PCs anymore for testing, but a pair of MACs do work fine.
I wonder if this is a known Windows 7 issue, and how can be fixed.
Answer: Try disabling TCP receive window autotuning:
<code>netsh interface tcp set global autotuning=disabled
</code>

Network issues in Windows 7


Is there a way to make a dynamic world such as a MMORPG horizontally scalable?

Question: Imagine a open-world of 500+ players with data changing as fast as 20 updates/player/second. Last time I worked in a similar MMORPG, it used SQL, so obvioulsy it couldn't query the DB all the time. Instead, it loaded all players from the DB to memory as C++ objects and used them. That is, it scaled vertically. Would it be possible to make that server horizontally scalable instead? Is there a database designed to support that amount of updates concurrently?
Comment: If you really, really think that different machines (or even processes) need 20Hz updates on hundreds of objects then completely bypass the database and use a messaging system directly.  But what you really, really think you want is not what you really want.  What you want is to have a sane scope of who needs to know what and then have a way to neatly transport objects between scopes on top of that.  You should answer the question of why you need 20Hz updates between different machines for great answers, someone might think of a new way to look at the problem.
Comment: I saw this on HackerNews a little while ago: http://paralleluniverse.co/ They are working on a database that does all of the spatial segmentation/distribution stuff for you.  I would guess that under the hood, they're doing all of the things in the answers below.
Comment: Why do you want to update player in database 20 times/second?
Comment: @Balon that's where I'm confused. If I don't update it in database, just in memory, then I'll have different states between different machines. But I guess DB updates have some huge overhead so it's not really going to work for that amount of updates?
Comment: @PatrickHughes I don't know what I need, I'm just explaining how the game works. Characters move 2~3 tiles/second. A player hunting might be surrounded by a few monsters, so at least 10 tiles/player/second. Then there are items decaying on the floor, on the player's backpack. There are attacks moving in direction of the player, there are attacks moving in direction of the monster. There is the health decaying, the mana being used, timers applying poison damage to the player. So, things change really fast. This is the game design. How could such design be vertically scaled?
Comment: PS: I think that all of the answers down below here have good info for you to consider!
Comment: @tugs holy lord that's awesome, I can't thank you enough. How could that never be suggested to me before? ):
Comment: @Dokkat it is interesting, but also keep in mind the cons: it's new and a bit obscure, the cost is not clear, it's not the 'normal' way of doing things, and by using it one may be ceding control/responsibility over a critical piece of code.
Answer: Test case of 500 players all communicating, that's 250K streams of information flying around at 20Hz.  The internal bandwidth for that would be, assuming 100 bytes each message, about 500MB/sec.  Sounds ambitious.  Especially between processes.
If you segregate players to groups of 100, that lowers to 20MB/sec, and so on.  Which is why MMOs have zones, and in those zones little bubbles of influence, and so on downwards until bandwidth becomes reasonable.
The original problem can be stated that if you have 10 people all sharing realtime information, but you want 500 all sharing, that's an exponential growth of communication links and how can we get around that.  I'm afraid that there's no magic bullet that I've ever heard of that can magically make geometric progression go away.
Don't use a database to communicate, that's what messaging is for.  Use the database to enforce transactions and store info you don't want players to lose.  Most MMOs that I'm familiar with only update the database with dynamic player info every 1-10 minutes, or at handy points like zone transitions or entering "safe" zones in the design.
You may have to redesign the game's need for every player, no matter how far away, to have realtime updates of every other player's backpack contents.
Also change the update pattern from 20Hz to a speed based on distance, someone 1 mile away does not need to know that you moved 1 foot at exactly 230.6 seconds, then another foot at 231.4 seconds, they can deal with you moving 15 feet every 10 seconds.
Comment: Awesome and informative answer, thanks. But I might add that while the world changes at very fast pace, a player can only see other players immediately next to him. I don't see it as geometric - 500 players send info to the server; the server periodically sends info to those 500 players. It's linear, as I see. But the main point is on the 4th paragraph: if I only use the database for storage, then I'm loading data to memory. If I'm loading data to memory in a machine, I'm creating a desynchronized version of the world. That's what I don't get.
Comment: For 1 client: 1 msg out + 1 msg in = 2.  For 2 clients: 2 msg out, 2 msg in = 4.  For 3 clients: 3 msg out, 3 msg in = 9.  And so it goes.  It's like this: send a status msg, server sends result to me and the other 2 clients (1 in, 3 out) and 3 clients all doing that (1 in 9 out).  While it looks linear for just one client of the 3, you get to multiply that by all clients for the total throughput of the system.  As for desync, even processes on the same physical box are out of sync until the status message is created and sent, it's just a matter of where the pipe empties out, local RAM or net.
Answer: Use area of interest filtering.  If a world is broken into 3 servers, and the area on server 1 is nowhere near the area of server 3, there's no reason for them to share information about entities at all.
Likewise, on a single server, only send relevant information to clients.  If player A is on the totally opposite end of the map from player B, there's zero reason to send updates about B to A, or vice versa.
When you have multiple servers in a continuous world, you will have entities near an edge on server 2 that are close to entities on server 1.  You can send updates from the "authoritative" server for an entity to the other server (when appropriate), and likewise forward any messages to the authoritative server as appropriate.
Yes, in this case, one server will be slightly out of date for particular entities.  Don't try to solve that.  Just deal with it.  Assume that entities may be a little out of date.  Do any logic that needs up-to-date information only on the server that authoritatively owns the entities.  When an entity affects another, send a message and assume that it may take multiple game logic ticks before it is processed and your view updates.
This design also makes it much easier to thread a single server.  No entity should directly modify another, only send messages, and the local per-server/per-thread proxy caches should be assumed to be slightly out of date.
For example, if entity A attacks entity B, don't check the life of B and then send a death message if it hits 0.  Just send a "damaged" message, let the authoritative server for B handle it, and then handle any "entity-died" message sent out by server B later if entity A cares about that.
The same applies to any large, scalable non-games application.  A central database is not a magical instant-sharing technology.  Two servers must communicate with messages, asynchronously, in batches, in order to maintain high throughput.  Hence the popularity of technologies like AMPQ and the like.  Databases are for storage and support synchronization out of necessity allowing them to be used for communications, not because they are themselves meant for synchronization or communication.
Comment: Thanks, this ended most of my remaining doubts. Also you gave me the idea of separe the servers by players, not areas - this would look smoother. Each servers take care of x players. I really like this! Is this used? And also, there's just one more thing. As I've asked above, I've just learned about a new NoSQL database, Couchbase. It's supposed to be just like CouchDB, except with very fast write/read speeds: up to 200k updates per second! Maybe this could actually work as such a "real-time shared world model", or not yet?
Comment: I have no idea if that technique is used in the wild besides the usual coarse "sharding" of servers.  Just doing it by players and geographical area means each server might need to be aware of a very large number of entities across a diverse set of areas, increasing server load and greatly increasing inter-server communication.  Doing it by area means your server might get over-loaded on crowded areas (though you can dynamically split and join areas in that case), but means that each server has a smaller set of relevant non-player entities and geometry to keep track of.
Comment: @Dokkat: It might be possible to have some kind of "soft areas" where you have each server mainly handling players in a particular part of the game world, but have them transparently hand over the player to another server if they stray too far from their original server's region.  You'd just need to make sure the handover is smooth enough that players don't really notice it.  You could even try to use some fancy adaptive techniques to keep clusters of interacting players on the same server, even if they happen to be just on a region boundary.
Answer: You will be probably interested in this article on Gamasutra, where Eve Online developers discuss how it's possible to succesfully run a game with 400 000 active players... in one SQL database.
Answer: Don't think of the database as some kind real-time shared world model storing everything about everything at all times — as you've noticed, that can't possibly work.
Instead, treat the database more like an automatically-updated save file: you update the database only occasionally, such as when players log in or out or move from one zone to another, or whenever something important happens that you don't want to be lost in case of a server crash.
The actual real-time world state should be held by the game servers, in memory, just as in your original example.  Now, the trick for horizontal scaling is that not every server needs to know everything at every moment.  For example, if player A is playing in zone A on server A, server B running zone B doesn't usually need to know what player A has in their backpack — and, if it does need to know that for some reason (say, because player B in zone B casts some kind of remote spying spell on A) it can just ask the other server for that information.
This does require you to assign clear responsibilities to the servers, so that when server B wants to know about player A's backpack, it will know which server has the authoritative information on that.  You will also likely want to include some kind of update subscription mechanism, so that e.g. server B can just tell server A "I have someone spying on player A, keep me updated about everything they do until I tell you otherwise."  You will probably also want to include some kind of global broadcast system for important global events that players may need to know about no matter where they are; of course, such events should also be recorded in the database, but having them actively broadcast to all server means that the servers won't have to keep polling the database for updates.
Comment: Awesome answer! This was precisely what I was asking, thank you. So perhaps the key is to divide the server in areas, keeping the logic in the on memory. Might I add, though: I've just learned about a new NoSQL database, Couchbase. It's supposed to be just like CouchDB, except with very fast write/read speeds: up to 200k updates per second! Maybe this could actually work as such a "real-time shared world model", or not yet?
Comment: @Dokkat no, it won't. Couchbase isn't magic.
Answer: Other responses have done a good job of pointing out how to use a database, and not to use a database for communication.  One other aspect that you might look into is to categorize your updates based on how the information needs to be communicated to other entities.  Rather than scope communication to servers, you could distribute your messaging and use pubsub mechanisms for communicating updates between entities.  For instance, you might treat location differently based on who's close to you:

Precise, real-time location might be useful within radius R
Less-precise, less frequent location updates might be useful within radius 2*R
No location information might be needed beyond radius 2*R

You might communicate location information for an entity by periodically scanning for entities within radius 2*R (or some multiple of that based on update rate and maximum velocity of an entity), and subscribing the entity to the other entity's precise or imprecise location feed.
You could have different strategies for different types of information, group common things into the same message queues, or have different queues for messages that need to go to different entities (or just send them to the broadest set of entities and have messages discarded if they're not useful).


Specific blog ideas

Question: List specific blog article ideas that the community has.  One idea per answer.   List specific ideas that you think you would like to see either as a reoccurring theme or a particular topic you would like to see more information about via the blog.
Answer: We could have a series of posts authored by the winners of the weekly featured image contests. The creator of the image would do a short post explaining what inspired the shot and/or how s/he achieved the effect in the photo. It's easy, it's relevant to the site, and there will always be material for it. (This would, of course, require that the weekly featured image winners be willing to do that, but I think it would be a neat series. Even as an occasional thing - once every three or four weeks, since I'm sure not everyone will want to write.)
Comment: Great idea, Laura. Jeez, the guys at Stack Exchange should give you a job! ;)
Answer: Lightroom Tips and Tricks
(alternatively, Lightroom Fundamentals)
This would be a series of articles dedicated to teaching readers about the full power and flexibility of Adobe Lightroom. It would start simple and general, and progress through more advanced tools, tips, and techniques.
I am working on an initial draft for the first installment, which would cover in general how to use lightroom to import and manage catalogs of photos, efficiently perform keywording, flagging and tagging, etc.
Comment: This would be great. Being new to Lightroom I've picked and pecked my way to getting a decent workflow down but I'd love to see some other ideas.
Comment: Aye, Lightroom can be tough to use if you don't use it the way it seems to be intended to be used. Plus, it has a lot of less-than-obvious features that can greatly improve ones workflow.
Comment: Guess I should note that there are two articles in the Lightroom Fundamentals column on our blog now. Go have a look, let me know what you think!
Answer: What gear did you recently buy.
I'm thinking that a lot of folks here hem and haw about the next lens, camera body, tripod, heck even filter they are going to purchase.  A blog post about what research you did, why you bought, what was the need, what did you compare it to etc. would be interesting.  Seeing others though processes on paper would provide some insight.
Comment: I like this idea. A more "personal" and practical approach to gear reviews, with the buying process involved. Sounds intriguing!
Answer: In a similar vein to Jrista's idea, Photoshop tips and tricks, perhaps a beginner's series.
Answer: Home Studio Setup on Budget
This could be a two post series describing the essential elements one would like to setup in their home studio i.e different lights, umbrellas, stands, backdrops, reflectors and what are the results achievable from the setup. We have a lot of online resources listing the gears one would likely to need, but few of them tells you why you actually need it and sample ways they can be used. A third post could be made discussing the future improvement possibilities in case someone decides to turn it into a full-fledged home studio.
Answer: Not sure if this is the place for this but an idea for a blog post is a Q and A of a specific person. This would involve a bit of work and get some cooperation with a few people but I would like to see an Interview on the blog with an astronaut about photographing the earth. I was reading a blog post by Don Pettit (as of this posting on board the ISS) and he spoke of photographing the earth and had this to say:

Even with a shutter speed of 1/1000th of a second, eight meters (26 feet) of motion occurs during the exposure. Our 400-millimeter telephoto lens has a resolution of less than three meters on the ground. Simply pointing at a target and squeezing the shutter always yields a less-than-perfect image, and precise manual tracking must be done to capture truly sharp pictures. It usually takes a new space station crewmember a month of on-orbit practice to use the full capability of this telephoto lens.

I was amazed at those facts and would love to have a Q/A about how it is done, what his techniques are, etc. Not sure if anything he would say would apply to the photography on earth it is still would be an interesting read.
Answer: Android phones for photography. I'm lookin' at @Imre here. :)
What Android phone has the best camera?
Answer: Picking from all the answers, I think that a blog post should be more informative than an answer cause it usually can be longer and the user expects that. In my opinion the blog post is not distracting as different answers to the same question and you are trying to pick the one that looks more correct (although this doesn't happen all the time ofcourse). I believe that the post should be specific and the author should put many details about what he is writing.
Examples

@Laura's idea is very nice actually. The winner of a week contest can write in details everything about the winning photo. Starting from planning to take the photo to actually taking it and what settings did s/he use and why? What was in his/her mind and what effect s/he was looking for? How did s/he post-process the photo from the beginning till the end? I'm certain that there's a huge opportunity for learning new stuff here.
@jrista's idea is great! Usually when you watch a lightroom/photoshop tutorial it walks you through a specific feature in the program of how to do something. I would like to see tutorials of how to edit a photo from the beginning since we import it till the end and we export it. Different ideas and artistic views are really important here cause not all people agree on the same thing. But I believe that this will lead to a nice discussion.
@Thanh's I believe that his idea can be merged with the gear rental that @Laura is running.

At the end I like actually what PhoeoSE is trying to achieve through its blog. I think that the blog will be really helpful and informative. It's a way of gathering all the nice questions in PhotoSE and reformat them into meaningful related articles.
Answer: Inspired by gear rental program that @Laura's running now, it would be great if Stack Exchange can ask the professional photographers to write articles in the blog about anything they like related to photography.
Answer: Also we can pick very nice questions that have more than one answer and write an post about it. For example, my recent question has links to other questions and answers, all of these can be combined into one single post

Specific blog ideas


Life's issues as a meditation subject?

Question: Are life's issues and other practical problems appropriate as a meditation subject?
Any buddhist school, that focus on this type of meditation?
Answer: Vipassana is training to handle such life situation.
Associated with each life interaction and though is a sensation. You can look at the arising and passing away of the sensations with full equanimity.
In generally what happens is when you come in contact with vicissitudes of life you react with clinging and craving on how you Perceive the sensation hence creating fabrication.
You can think and ponder on the matter in hand. This is in fact verbal fabrications. Thinking and pondering will create other sensation. Most prominent even in no mediators are like happiness, depression, anxiety, anger, hate, etc. which also has feelings associated. In general thinking things these can also be neutral or very subtle. In the process of Thinking and Pondering again look at the associated sensations arising and passing away.
Comment: I highly appreciated your response. From your explanation I understand that my emotions around a given issue could be a subject for meditation.  Allow me to ask something else. The act of calmly pondering different options and making decisions can be a form of meditation?
Comment: @artificer Updated above. See if it answers whether this answers your question to satisfaction?
Comment: Yes it does. Thank a lot.
Answer: There is a meditation technique I got from Chogyam Trungpa Rinpoche called "touch-and-go". This is when you sit and let your mind expand naturally making no effort, and then when a thought about life issues comes up, you "touch" it (just to get a glimpse of its flavor) and then let it "go". This way you get to laundry a lot of your samskaras in a short period of time without getting bogged down in any one of them.
You don't go with the thoughts, you don't go against the thoughts. You do disidentify from the thoughts. You are not your thoughts. (You are not the observer of your thoughts either, but that's a separate story).
If the thought causes emotional pain, use the vajrayana transmutation technique: see the pain as pure somatic sensation until it melts under your stare. You are not your emotions.
Sometimes it maybe useful to trace your life issues, or rather the painful emotions associated with them, to preconceptions or attachments that come from overgeneralization of previous experiences. Once you learn to see your own experience-based biases and disidentify from them, you can be free of those as well. You are not your experiences.
Answer: To throw a monkey wrench into things as I'm wont to do, I'm going to say no.  It's not appropriate to use life issues as an object of meditation.  That's a lie, of course, but there's actually a different way of exploring the relationship between sitting and life issues that might give you a different perspective on your question.
There is a strong relationship between samatha meditation and insight in the Pali canon (and really the whole of Buddhism) that doesn't get much air play in the West anymore.  Not to discount vipassana at all - it is an exceptionally effective method of liberation - but tranquility meditation has a different emphasis.  It approaches our life issues, our obstacles, and our ignorance in a rather unique way.
The way samatha meditation works is that you sit with some sort of object be it your breath, a sign (e.g. kasina), or any one of a couple dozen other meditation devices.  It wouldn't be appropriate to use a life issue for this sort of meditation.  What you are trying to do is calm your mind and enter into successive states of concentrated absorption called jhana.  Good luck trying doing that with anger, right?  These states of deep concentration purify the mind, temporarily release you from the five hindrances, and loosen the fetters that ignorance uses to bind your consciousness.
But this sort of concentration is no good unless you use it for something.  These absorption are nothing more than spiritual masturbation unless you take advantage of the perspective they provide.  This is where samatha practice asks us to turn our minds back to our life issues and obstacles.  In fact, this is exactly what the Buddha did.  In the Bhayabherava Sutta (MN 4), you'll find the Buddha ascending through the jhanas.  Upon reaching the fourth, he says -

When my concentrated mind was thus purified, bright, unblemished, rid
  of imperfection, malleable, wieldy, steady, and attained to
  imperturbability, I directed it to knowledge of the destruction of the taints. (MN 4.31)

With the purified mind afforded to him by the jhanas, the Buddha was able to directly penetrate into the very things binding him to samsara.  Had he not entered into so deep an absorption, the knowledge he was able to discover would likewise not have been so complete.
Think of it like Street Fighter.  You've got your light, fast hits that given enough time will eventually fell your opponent.  That's vipassana.  And it works.  What the Buddha did, however, was use one big ol' haymaker of an attack and knocked delusion out with one blow.  That's the power of samatha.  This is an approach that doesn't use life issues as the object of meditation, but uses those issues as grist for insight once a state of absorption has been attained.
(Side note - some people will even tell you that jhana or at least access concentration is necessary for vipassana to be effective.)
(Bonus side note - this is also exactly how koan practice works.  The answer to koans are discovered when you turn a concentrated mind back onto them.)
Answer: There is a highly recommended form of meditation in Buddhism called "Vipasana"
that is the solution for the question because it concentrate on the events in lie in a Buddhist perspective.
But you are not sitting down in peace every second,You play,work,talk and etc.
so how do you cope with events as they occur?
The solution is Mindfulness
Here are some teachings on meditation that might help with your issue.
Just a body with movement (Meditation of posturest full awarness)
 Slaughtered cow (Meditation on elements)
Answer: Sure, the Buddhas school takes it as primary object, and one should do such very often for long term happiness and to walk a path upwardly. Lifes issues, decay of all kind, breaking appart, ageing, sickness, death. Not possible to either train for liberation, get encouraged and not heedless, nor to get any insight without often taking lives issues, inwardly, outwardly, as an object of meditation.
At least it's also a main object of the 4. base for mindfullness:

"And further, the monk remains focused on mental qualities in & of themselves with reference to the four noble truths. And how does a monk remain focused on mental qualities in & of themselves with reference to the four noble truths? There is the case where he discerns, as it has come to be, that 'This is stress…This is the origination of stress…This is the cessation of stress…This is the way leading to the cessation of stress.'[19]
[a] "Now what is the noble truth of stress? Birth is stressful, aging is stressful, death is stressful; sorrow, lamentation, pain, distress, & despair are stressful; association with the unbeloved is stressful; separation from the loved is stressful; not getting what is wanted is stressful. In short, the five clinging-aggregates are stressful.
"And what is birth? ... mn 10

Meditator who do not do meditate and reflect on lifes real issues, don't develope samvega and see urgency, are just wellness-meditators and sure to gain not much aside of short time escape. Never would leave home and strive for liberation.
Beware of those practicing householder-equanimity and ignoranz for eatings and being eatens sake.
(Note: this is not given for any trade, exchange, stacks and entertainment, but as an exit out of this wheel here and now)
Answer: In Theravada Buddhism, it's called Sila. There are 2 kinds of Sila:  Sila to avoid and Sila to do. See MangalaSuta, Siṅgālakasuttaṃ and 1st chapter of Path of Purification.
I think, Sila is common for the educated people around the world, especially the strict temples such as Pa-Auk, Ajarn Cha, etc.

The practitioner should practice Sila but Sila is not meditation because...

Sila is the basis of the meditation because the ruthless person can't succeed the meditation in long term.
Sila focuses to physical actions, bodily and verbal, of mind but the meditation focuses on  mind process directly.

Life's issues as a meditation subject?


"Catch" vs "Take" a Bus/Train

Question: Could anyone help me with finding the difference between saying "catch a bus/train/etc" and  "take a train/bus/etc"? I'm afraid I haven't been able to glean one from my dictionary.
Answer: Catching a bus describes the process of getting to a stop/station, waiting and boarding.
Taking a bus describes the entire process, including the journey itself.
Much of the time, the distinction isn't important. For example:

"How did you get to work today?"
"I caught a bus." (The listener infers that having caught the bus, you stay on it)
"I took the bus." (You have described the journey)

However, it could be relevant:

"I read a book while I was taking the bus" (yes: reading while the bus is moving)
"I read a book while I was catching the bus" (unlikely: reading while stepping onto the bus, paying the driver, etc.)

It is a similar meaning to catch as catching a fish, or catching a ball. You and the bus are apart, and then you bring yourself into contact with it through your own effort. If you try to catch a bus, and fail, you miss it.
One other thing, you catch a bus at a specific place:

"You can catch the bus to Coventry on Smith Street"

But you take the bus from a place:

"You can take the bus to Coventry from Smith Street"
Answer: The sixth definition of the verb catch is listed as: to be in time to get aboard a train, boat, etc.
Whereas for the verb take you have to make your way down to definitions number 46 and 47 to read:

46) to use as a means of transportation: to take a bus to the ferry.
  47) to get on or board (a means of transportation) at a given time or in a given place: She takes the train at Scarsdale.

You can either catch or take the:

train
bus / coach
boat / ship
ferry
plane

These means of public transport will stop and pick up passengers waiting at a platform, bus stop, harbour, port or at an airport gate. To catch also evokes the image of a person running towards that stop, platform etc. in order to board the transport.
Until the 1980s many of London's double-decker buses —Routemasters—, had an open rear platform with a sturdy pole attached that allowed passengers to "hop-on" and "hop-off". It was a common spectacle to see people running and grabbing hold of the pole as the bus moved away from the stop. Therefore, literally catching the bus at that moment.  The last Routemasters were withdrawn from regular service in December 2005.
You take the:

bike
motorcycle/motorbike
car
van
taxi/cab *

The above are not usually considered means of public transport as these vehicles do not stop at specific locations to pick up passengers. However, some speakers might say "catch a taxi" in place of the idiom hail a taxi, which I believe, is becoming rare.
Answer: "To catch the bus" originated from the original method of hopping onto a moving bus.  You had to "catch" the bar and running board of the bus in order to ride it.  Circa 1920.
Answer: The meaning common to "catch" and "take" in these idiom is "travel by". And there is very little difference. If there is one, it's in the tone. "Take" implies you have control over the mode of transportation; "catch" implies you have to fit your schedule to it. So if you were writing fictional dialog, a more dynamic character might "take" whereas a more passive character might "catch".

"Catch" vs "Take" a Bus/Train


What links can be made between the marginal productivities of the factors of production and the costs of production

Question: What links can be made between the marginal productivities of the factors of production and the costs of
production
Answer: Assume the following profit function: $\pi = pY - wL -rK$ and a two factor economy $Y(L,K)$.
Optimal labour and capital inputs for the firm can be found by taking the respective derivatives and setting them to zero:
$\frac{\delta \pi}{\delta L} = p \frac{\delta Y}{\delta L} -w = 0  \iff \; \frac{\delta Y}{\delta L} = \frac{w}{p} $
$\frac{\delta \pi}{\delta K} = p \frac{\delta Y}{\delta K} -r = 0  \iff \; \frac{\delta Y}{\delta K} = \frac{r}{p} $
Now you can see that marginal productivities are equal marginal costs. The derivative with respect to the input factor tells you what the next unit of capital or labour will produce and the right hand side tells you what they will cost (real wage or real interest rate). If this condition does not hold firms could be better off by adjusting their production towards this condition. For example assume marginal product of labour is greater than the real wage $(\delta Y / \delta L > w / p)$. The firm should hire an additional worker since she will produce more than she costs. This logic holds true until the conditions are fulfilled.
Answer: In a perfectly competitive markets for factors of production the marginal productivity of factors is equal to price of factor, which in turn decides the cost of production. For example, consider two factor production function $Y=F(K,L)$. At equilibrium, under assumption of perfect competition in market for both factors, $F_K = r$ and $F_L = w$, where $F_K, F_L$ are marginal products with of $K$ and $L$ respectively, and $r, w$ are respective prices of these factors.
Cost of production is $$C(Y)=rK+wL=F_K\cdot K+F_L\cdot L$$
This is the simplest link between marginal productivities and cost of production. In a partial equilibrium setting, with $r, w$ given, this can be further simplified to eliminate $K$ and $L$ (see equation (6) in this answer)


How do I prevent delimiters in a URL from being URL encoded?

Question: I need to know how to get a +-delimited string to be appended to the end of the URL path without the + character being URL encoded.
Why: I'm trying to pass arguments to a View. I'm working on a custom module to conditionally route webform confirmations to a View. The view will take multiple arguments, returning all nodes matching the arguments (currently trying to do this with Views 3.0).
I've done proof-of-concept tests on the view that demonstrate that for a view with a path of, say, cbos/name1+name2 it will produce the desired result (i.e., displays nodes name1 and name2). So I know that this can be done from the Views side. (I'm pretty certain at this point Views has nothing to do with it, I just need to make clear why I need to do this.)
The problem is on the custom module / webform side.
I'm creating the URL path using the following code:
while ($cbo_short_name = db_fetch_array($result)) {
if ($count > 0) $delim = '+';
$cbo_short_names_arg .= $delim.$cbo_short_name['cbo_short_name'];
$count = $count + 1;
}
$redirecturl = "cbos/".$cbo_short_names_arg;
$node->webform['confirmation'] = drupal_urlencode($redirecturl); // ... have also tried setting this via the form settings page using tokens

... where $cbo_short_name is an array of short names (usually initials) for organizations. (There's usually only 1, but in about 15% of cases there will be 2 or 3 short names. The visitor has to be shown all of them. Hence, the View)
What this should do is produce a URL path of the form given above; what's happening is that '+' is getting URL encoded as %2B (e.g. cbos/name1%2Bname2), which breaks the Views argument string -- only the first result is returned.
If I could somehow force '+' to be passed intact, without URL encoding, this would work. But I'm at a loss for how to do that.
What I've tried so far:

Setting the confirmation URL on the form settings page (preferred,
since I don't have to hard code it).
Setting the redirect URL
programmatically (what you see above).

Both work to set a value, but in both cases the delimiters are URL encoded in the resulting URL path.
Answer: I am sure I am missing a or the point here, but, could you do something like this:
while ($cbo_short_name = db_fetch_array($result)) {
  if ($count > 0) $delim = '+';
  $cbo_short_names_arg .= $delim . drupal_urlencode($cbo_short_name['cbo_short_name']);
}
$redirecturl = 'cbos/' . $cbo_short_names_arg;
$node->webform['confirmation'] = $redirecturl;

eg, sanitize your arguments but then glue them together with the + (that isn't encoded) ?
Answer: I don't think there is any build in Drupal helper function to do so, there is drupal_http_build_query to build query but it support only &as separator.
I think you should get your hand dirty a little bit and implement something for your use case take a look at this discussion about how to prevent drupal_goto from encoding plus and comma characters?
for your use case there is this suggestion
and also this suggestion.
But first try with something like, add a function in your module like :
function custom_drupal_encode_path($path) {
  return str_replace(['%2F', '%2B'], ['/', '+'], rawurlencode($path));
}

and test with:
$node->webform['confirmation'] = custom_drupal_encode_path($redirecturl);


How to correct outliers once detected for time series data forecasting?

Question: I'm trying to find a way of correcting outliers once I find/detect them in time series data. Some methods, like nnetar in R, give some errors for time series with big/large outliers. I already managed to correct the missing values, but outliers are still damaging my forecasts...
Comment: Are the outliers "real"?  By this I mean are outliers caused by the inability of the model to predict extreme events or shocks?  Or are they "errors" such as data entry problems?
Comment: what do you mean by "correcting"?
Comment: Substituting or replacing... Or should it be just subtracting...?
Answer: There is now a facility in the forecast package for R for identifying and replacying outliers. (It also handles the missing values.) As you are apparently already using the forecast package, this might be a convenient solution for you. For example:
fit <- nnetar(tsclean(x))

The tsclean() function will fit a robust trend using loess (for non-seasonal series), or robust trend and seasonal components using STL (for seasonal series). The residuals are computed and the following bounds are computed:
\begin{align}
U &= q_{0.9} + 2(q_{0.9}-q_{0.1}) \\
L &= q_{0.1} - 2(q_{0.9}-q_{0.1})
\end{align}
where $q_{0.1}$ and $q_{0.9}$ are the 10th and 90th percentiles of the residuals respectively.
Outliers are identified as points with residuals larger than $U$ or smaller than $L$.
For non-seasonal time series, outliers are replaced by linear interpolation. For seasonal time series, the seasonal component from the STL fit is removed and the seasonally adjusted series is linearly interpolated to replace the outliers, before re-seasonalizing the result.
Comment: Your elaboration here is helpful too: http://stats.stackexchange.com/questions/1142/simple-algorithm-for-online-outlier-detection-of-a-generic-time-series#answer-1153 (tsclean calls tsoutliers)
Answer: When you identify an ARIMA model you should be simultaneously identifying Pulses/Level Shifts/Seasonal Pulses and/or Local Time Trends. You can get some reading material on Intervention Detection procedures. I recommend "Time Series Analysis: Univariate and Multivariate Methods" by David P. Reilly and William W. S. Wei.
You may have to pursue commercial software like SAS/SPSS/AUTOBOX to get any useful results as the free software I have seen is wanting. In passing, I have contributed major technical improvements in this area to AUTOBOX.
EDIT:
An even better approach is to identify the outliers using the rigorous ARIMA method plus Intervention Detection procedures leading to robust ARIMA parameters and a good forecast. Now consider developing simulated forecasts incorporating re-sampled residuals free of pulse effects. In this way, you get the best of both worlds viz a good model and more realistic uncertainty statements for the forecasts which don't assume that the estimated model parameters are the population values.
Answer: I agree with @Aksakal.
Instead of removing the outliers, a better approach would be to use some kind of statistical procedure to deal with the outliers.
I suggest you winsorise your data. If implemented properly, winsorisation can be relatively robust to outliers.
On this page: http://www.r-bloggers.com/winsorization/, you will find R-codes to implement winsorisation.
If you consider winsorising your data, you will need to think carefully about the tails of the distribution. Are the outliers expected to be extremely low, or are they expected to be extremely high, or maybe both. This will affect whether you winsorise at e.g. the 5% or 10% and/or the 95% or 99% level.
Comment: Winsorization, for the purpose of estimating an overall mean, might make some sense in the absence of any trend or seasonal components in the data, but otherwise threatens to destroy important information.
Answer: In the forecasting context, removing outliers is very dangerous. For instance, you're forecasting sales of a grocery shop. Let's say there was a gas explosion in the neighboring building, which caused you to close the shop for a few days. This was the only time the shop was closed in 10 years. So, you get the time series, detect the outlier, remove it, and forecast. You silently assumed that nothing like this will happen in the future. In a practical sense, you compressed your observed variance, and the coefficient variances shrank. So, if you show the confidence bands for your forecast they'll be narrower than they would have been if you did not remove the outlier.
Of course, you could keep the outlier, and proceed as usual, but this is not a good approach either. The reason is that this outlier will skew the coefficients.
I think a better approach, in this case, is to allow for an error distribution with fat tails, maybe a stable distribution. In this case, your outlier will not skew the coefficients too much. They'll be close to the coefficients with an outlier removed. However, the outlier will show up in the error distribution, the error variance. Essentially, you'll end up with wider forecast confidence bands.
The confidence bands convey a very important piece of information. If you are forecasting that the sales would be \$1,000,000 this month, but there's a 5% chance that they'll be $10,000, this impacts your decisions on spending, cash management, etc...
Answer: To perform forecasting using a model with outliers removed depends on the probability of outliers occurring in the future and the expected distribution of its effect if it indeed occurs. Is the training data sufficient for illuminating this?. A Bayesian approach should help...
Comment: This is incorrect. your forecast may be inaccurate if you don't adjust for outliers, especially if your outliers are at the end of the series.


Heterochromatin binding sites position information

Question: I am working on a project and I'm trying to find data on the position of genes and heterochromatin binding sites such as HP1 in Drosophila melanogaster. Is this information available for the DGRP lines? Would I be able to measure the distance between a gene and its nearest binding site from such data?
Answer: Have a look at these ChIP-seq data for HP1 in Drosophila: 1, 2 and 3. From ChIP-seq data you can find the distance between the TFBS peaks and the TSS of the gene.
You can also look for nucleosome positioning and DNAse hypersensitvity regions; for the former, I am sure that data is available for Drosophila.
Answer: As the previous answer said, there are some public HP1 ChIP-seq data from D. melanogaster if not from the DGRP, from modENCODE and maybe others. In the case of modENCODE, they've published not only the reads, but also their peak calls (mapping with Eland + calling with MACS).
BEDTools ( https://github.com/arq5x/bedtools2 )is a nice command line tool for manipulating intervals with genomic coordinates, and the bedtools closest command can calculate the distance to the closest feature. It would look something like this:
<code>bedtools closest -d -a genomic_features.gff3 -b peak_calls.gff3
</code>
Where the "genomic_features" part would be any subset of genome annotation that you're interested in.
I've worked through a small example with modENCODE data, Flybase transcript annotation and BEDTools:
http://martinsbioblogg.wordpress.com/2014/07/04/finding-the-distance-from-chip-signals-to-genes/
Cheers,
m.