14.12 To determine whether training in a series of workshops on creative thinking increases IQ scores, a total of 70 students are randomly divided into treatment and control groups of 35 each. After two months of training, the sample mean IQ (-X1) for the treatment group equals 110, and the sample mean IQ (-X2) for the control group equals 108. The estimated standard error equals 1.80.

Question:

Using t , test the null hypothesis at the .01 level of significance.

What is the research hypothesis?

What is the null hypothesis?

Is this a one-tailed or two-tailed test?

What are the degrees of freedom?

What is the t critical for .01 significance?

What is the calculated t?