Recently UC Santa Barbara received a large grant from Acme I

Recently UC Santa Barbara received a large grant from Acme Inc. As part of the grant 20 personal computers were given to the university as well as a series of instructional software programs designed to improve writing skills of college students. An educational researcher decided to evaluate the usefulness of these programs and designed the following experiment for that purpose. After announcing the project to several large classes on campus, 30 students volunteered to participate in the study. Ten students were randomly assigned to one of the three groups. Group 1 was instructed on how to use the PC and the writing programs. Group 2 learned how to use the word processing program but received no instruction on improving their writing skills. The 3^rd group received no special instruction and served as a control group. Before beginning the treatment all students were asked to write a 2000 word essay with the instruction to

Solution

Probability of Type I Error (?) = 0.05
Sample size = 30
Correlation coefficient observed (?) = 0.70

Using a power calculator with the above parameters, the power is found out to be 0.9983
Therefore, Power of study = 0.9983