The document analyzes test score data from 20 sample students who took tests in June 2010 and January 2011. It finds that on average, total test scores increased by 1.05 points in January compared to June, while multiple choice scores decreased by 1.05 points and essay scores increased by 0.65 points. This leads to the conclusion that the evidence does not support one test being more difficult than the other, so there was likely no test bias.