This preview shows page 1. Sign up to view the full content.
Unformatted text preview: free to vary when computing SS for sample data. The value of df also describes how well a t statistic estimates a z-score. t distribution: The distribution of t statistics is symmetrical and centered at zero like a normal distribution. A t distribution is flatter and more spread out than the normal distribution, but approaches a normal shape as df increases. (r2 ) the percentage of variance accounted for: A measure of effect size that determines what portion of the variability in the scores can be accounted for by the treatment effect....
View Full Document
- Spring '11