June 2015 – czxttkl

Install Latex distribution, editor and packages on Ubuntu

1. Install TexLive. This is the latex environment. https://www.tug.org/texlive/quickinstall.html We recommend to use .install-tl script to install TexLive. TexLive is usually installed at “/usr/local/texlive/year/bin/x86_64-linux/….” Although you can install vanilla TexLive via sudo apt-get install texlive, we often observe it misses advanced accessories such as fonts. 2. Install Texmaker http://www.xm1math.net/texmaker/ *** Note: On Ubuntu, Texmaker can …

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LDA Recap

It’s been half year since last time I studied LDA (Latent Dirichlet Allocation) model. I found learning something without writing them down can be frustrating when you start to review them after some while. Sometimes it is a bit embarrassing that you feel you didn’t learn that at all. Back to the topic, this post …

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Collection of statistical hypothesis tests

This post is a collection of hypothesis test methodologies. The full collection is listed here: http://www.biostathandbook.com/testchoice.html. My post just goes over several hypothesis tests that are relevant to my research. One-way ANOVA: http://www.biostathandbook.com/onewayanova.html If you have one measurement variable and one nominal variable, and the nominal variable separates subjects into multiple groups, you want to test …

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Factor Analysis and PCA

I’ve been scratching my head for a day (06/24/2015) but it ended up that I am still baffled by the concept of Factor Analysis. So first of all, let me list what I’ve learned so far today. PCA and Factor Analysis can be deemed similar from the perspective that they are both dimension reduction technologies. …

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Unclean uninstallation of fcitx causes login loop on Ubuntu

Whether you realize or not, fcitx, a popular input method, if not properly uninstalled, can cause the notorious login loop issue on Ubuntu (i.e., every time you type your password and enter, you get asked to type your password again on the same login window). Here is the post talking about how to fully uninstall …

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alsamixer automatically mutes headphones and speakers

http://askubuntu.com/questions/280566/my-headphones-mute-alsamixer-when-i-plug-them-in-hp-dv6-12-04 http://askubuntu.com/questions/541847/is-there-any-way-to-save-alsamixer-settings-other-than-alsactl-store The two links above are two popular links about dealing with the auto-mute problem of alsamixer. However, the two don’t help my situation. My solution 1. Type the following command: sudo alsamixer 2. Use `RightArrow` key to navigate to right until you see “auto-mute” 3. Use `UpArrow` or `DownArrow` key to set …

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Learn LSTM in RNN

Long Short Term Memory is claimed to be capable of predicting time series when there are long time lags of unknown sizes between important events. However, as to 2015.6, not many clear tutorials have been found on the Internet. I am going to list a collection of materials I came across. Probably I will write …

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How to fully backup your ubuntu system?

http://askubuntu.com/questions/7809/how-to-back-up-my-entire-system

PCA和SVD的关系

Update 07/15/2015: First, we should know how to calculate covariance matrix and correlation matrix. According to the wikipedia page, we have the calculation procedure of covariance matrix as: And the calculation procedure of correlation matrix is: I am going to use an R example to illustrate the calculation procedures. Let’s say we have a …

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Northeastern University Connect to NUWave on Ubuntu

For faculty and students: you need to configure exactly as follows (except username & password) to connect NUWave at Northeastern University: