RapidMiner and TTests

RapidMiner doesn't come with a way to test the probability that the difference in two groups' attributes is statistically significant. (The operator they have called "T-Test" actually does an F-Test and compares the performance of two models, not two groups of data.)

I have created an operator that uses Welch's T-Test to help with this. See the code at github. I've also attached a screenshot showing it in action; this one is looking at sonar data and determining the probability that sonar differences between rocks and mines are significant.