clbustos/statsample — pull request #11 by jeremyevans (2012-08-22 21:18:27+00:00)
Title: Remove bad check in cronbach_alpha calculation

There is no reason to return nil if a single vector has a 0 variance. For example, let's say you are giving a test, and every single taker gets the easiest question correct. The variance for that question vector is 0, but Cronbach's alpha can still be calculated correctly for the entire dataset.