This Gist has a couple of things going on, I’ll just list them: It downloads the entire history of U.S. House DW-NOMINATE scores from voteview.com It evaluates aggregate statistics, with members grouped by party and congress, with easy weighted ...

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Problem When a correlation or covariance matrix is not positive definite (i.e., in instances when some or all eigenvalues are negative), a cholesky decomposition cannot be performed. Sometimes, these eigenvalues are very small negative numbers and occur due to rounding or due to noise in the data. In simulation studies a known/given correlation has to be imposed on an input...

The three benchmark algorithms for predicting the location of dark matter halos are, for the most part, all over the map. Most of the test skies look something like this: There are, however, some skies with rather strong halo signals that get a decent amount of agreement: The Lenstool MLE algorithm is the current state

Some people like to do crossword puzzles. I like to do machine learning puzzles. Lucky for me, a new contest was just posted yesterday on Kaggle. So naturally, my lazy Saturday was spent getting elbow deep into the data. The training set consists of a series of ‘skies’, each containing a bunch of galaxies. Normally,