I am participating in a Kaggle competition and I would like to know what is the best way to handle missing attribute values in test data set. For example, if the train data set contains the attributes (x, y, z, prediction) and the test data set contains (x, y), how do I predict "prediction"? Should I just take (x, y) parameters as features or try and predict the third(z) attribute. If the latter holds, how should I go about doing that? EDIT: Adding the link to the competition
I have a data set for a predictive model(predicting survival rate with certain acute medical condition on some animals) with 25 predictors where around 30% of the predictors are complete, 3 predictors are sitting at 30%,25% and 20% missing, and the others are missing at around 5% level. Around 50% of my data are complete cases. I'm new to dealing with missing values so I have a couple of questions regarding how to deal with it:   What can I do with the variable with 30% missing assuming it's MAR? Is 30% too high for imputation? What kinds of metrics can I use to make the decision between removal of the predictor, listwise removal, imputation or some other options? How should I deal with a predictor with 20% - 25% missing when I have reason to believe that it's MNAR? I'm thinking of using imputation on the remaining predictors with around 5% missingness. How do I make the decision on which imputation methods to use? Are they chosen on a case by case basis based on the individual predictors? How does one impute categorical values?  How does(should?) the imputation carry out in practice? Should it use complete cases or compute it iteratively somehow?  Does feature selection comes in before or after dealing with missing values? if at all?
What's the easiest way to download all albums from Google Photos? I have around 950 albums at Google Photos.      I want to back them up now, but organised by albums, not by date.   Whenever I create a backup from within Google Photos, the backup splits my photos by date and adds metadata here and there.  What I am doing now is to click on every album, and choose "Download all". But this will take me ages.  Is there a way through Google Drive or another app to have a easier job? How to get next/previous record in MySQL? Alien studying human race for mental capacity and ESP How do I make a Theorem n followed by a Theorem n' ? How can I read off the fact that gravity is associated with spin-2 particles from the Einstein-Hilbert action? I have often heard that the gravitational field has spin $2$. How can I read the spin of the field from the Einstein-Hilbert action  $$S=\int \! \mathrm{d}^4x \,\sqrt{|g|} \, \mathcal{R} \, \, \, ?$$ How can I left-align a caption? I am using this for captions:  \usepackage[font=small,format=plain,labelfont=bf,up,textfont=normal,up]{caption}   But they all come out centred - I want them aligned with the left margin - how can I do this? Can I travel within the Schengen area if I currently don't have a valid visa or residency permit? I am getting my feet wet with Git and have the following issue:  My project source tree:  / | +--src/ +----refs/ +----... | +--vendor/ +----...   I have code (currently MEF) in my vendor branch that I will compile there and then move the references into /src/refs which is where the project picks them up from.  My issue is that I have my .gitignore set to ignore *.dll and *.pdb.  I can do a git add -f bar.dll to force the addition of the ignored file which is ok, the problem is I can not figure out to list what files exist that are ignored.  I want to list the ignored files to make sure that I don't forget to add them.  I have read the man page on git ls-files and can not make it work. It seems to me that git ls-files --exclude-standard -i should do what I want.  What am I missing? How to connect to device via SSH over direct ethernet connection Houston, we have a porblem Since  in titles, and there's not even a way  (or ) we all know users just get around that filter by typing various permutations of the word "problem".  The filter has . The bottom line there was:     "Hacking around" the filter is in fact very very rare.   I beg to disagree. I tried searching Stack Overflow for the following variations of the title:  problme probelm probeml probmle probmel prolbem prolbme prolebm prolemb prolmbe prolmeb proeblm proebml proelbm proelmb proembl proemlb   These are just a couple of permutations from 5040 possible ones. I also tried searching for variations with left out letters, like proble, or prblm. Here's just a graph of a subset from maybe 20 searches—but in reality, there might be more ways to get around the filter:    Was this ever intended? I know it saves a lot of bad titles from being created, but on the other hand it enforces even worse titles as well. 3% based on the  aren't much, but they're 3% crap the filter actively provokes.  Now, my questions up for discussion are:   What are we going to do about this large number of porblematic posts? It seems almost impossible to fix all those. We now have a really good review system that allows people to dig through low quality posts the entire day, so that'd be a way to address this of course. Are there any plans of getting rid of the filter again? This, at least, would give you a good indicator of poor quality. If a post title contains the word "problem" you instantly know something's off. Why not have it reviewed? I understand that some people will choose a better title after being blocked, but I don't even want to start looking at the number of those who merely did a s/problem/issue, or even worse, just used "problems" (because that's not blocked, just sayin').   In the end I'm just thinking if there was a way to clean up the back log on this, or how to prevent more posts of this sort in the future, even with a title filter in place if it has to be. I'm try to change to my Desktop directory from the terminal.  Running  cd /home/desktop   gives an error in the terminal saying no directory found.  What am I doing wrong? I am trying to figure out how can I disable/hide the App Name in MacOS X Lion dock. I've also attached an image so you can see what I mean.    Someone has any idea about how can I hide that? Why doesn't the height of a container element increase if it contains floated elements? Pointer Arithmetic Does anyone have any good articles or explanations (blogs, examples) for pointer arithmetic?  Figure the audience is a bunch of Java programmers learning C and C++. More than one time dimension We know that space-time dimensions are 3+1 macroscopically, but what if 2+2?  Obviously it is tough to imagine two time dimensions, but mathematically we can always imagine as either having two parameters $t_1$ and $t_2$ or else in Lorentz matrix $$\eta_{00} = \eta_{11} = -1$$ and, $$\eta_{22} = \eta_{33} = 1.$$  Is there any physical reason for not taking this, like the norms become negative or something else? Is there a general formula for finding the primitive of $$e^{ax}\sin(bx)?$$  I've done this manually with $a=9$ and $b=4$ using Euler's formulas. But it takes a bit of time. Is there a pattern here? mixed declarations and codes Copy & Pasting from Photoshop to Illustrator loses transparency I often run into this issue. I'm creating a file in Photoshop with masked layers etc. I want to make the final output available for some mock-ups in Illustrator, so I rasterize the layers and marquee select the entire area, copy and move to Illustrator.  Pasting the area in Illustrator flattens all transparencies, which is quite annoying. I'm left with my object and a flat white background.  Is there a reason for this? I guess it is too difficult a question to ask about the cardinality of $S_{\mathbb{N}}$ so I would like to ask whether it is countable or not.  I tried to prove it is uncountable somewhat mimicking the Cantor's diagonal argument but failed. How to cut a mesh by specifying the angle