sure enoughit worksi get much prettier graph now that excludes donald trump and focuses in on the more typical dataset here in the center sopretty cool stuffsothat' one example of identifying outliersand automatically removing themor dealing with them however you see fit rememberalways do this in principled manner don' just throw out outliers because they're inconvenient understand where they're coming fromand how they actually affect the thing you're trying to measure in spirit by the wayour mean is also much more meaningful nowmuch closer to , that it should benow that we've gotten rid of that outlier activity for outliers soif you want to play around with thisyou know just fiddle around with it like normally ask you to do try different multiples of the standard deviationtry adding in more outlierstry adding in outliers that aren' quite as outlier-ish as donald trump you knowjust fabricate some extra fake data there and play around with itsee if you can identify those people successfully so there you have itoutlierspretty simple concept sothat' an example of identifying outliers by looking at standard deviationsand just looking at the number of standard deviations from the mean or median that you care about median is probably better choice actuallygiven that the outliers might be skewing the mean in and of themselvesrightsoby using the standard deviationthat' good way of identifying outliers in more principled manner than just picking some arbitrary cutoff againyou need to decide what the right thing to do is with those outliers what are you actually trying to measureis it appropriate to actually discard them or notsokeep that in your headsummary in this we talked about the importance of striking balance between bias and variance and minimizing error nextwe saw the concept of -fold cross-validation and how to implement it in python to prevent overfitting we learned the importance of cleaning data and normalizing it before processing it we then saw an example to determine the popular pages of website in $ibqufsapache spark machine learning on big data we'll learn machine learning on big data using apache spark