Mr. Washington allows his lesson times to go with the flow;…

Mr. Washington allows his lesson times to go with the flow; that is, he simply begins teaching in the morning and lets each lesson last as long as it needs to last. He also varies the order of his content presentations, doing math first on some days and reading first on other days. He may allocate an hour to science on Monday, not teach it at all on Tuesday, and give it half an hour on Wednesday. How would you evaluate his system?

In an independent t-test, we calculate a mean difference bet…

In an independent t-test, we calculate a mean difference between the groups (group 1 –  group 2) and we use this to test against the null.  If the mean difference and 95% confidence intervals are 4.1 (95% CI -2.5 to 10.0), would you reject the null hypothesis?