1. You are planning a study that you compute as having quite low power. Name six things that you might do to increase power.
2. A psychologist is planning a study on the effect of motivation on performance on an attention task. In this task, participants try to identify target letters in a stream of letters passing by at a rapid rate. The researcher knows from long experience that under ordinary experimental conditions, the population of students who participate in this task identify a mean of 71 of the key letters; the standard deviation is 10; and the distribution is approximately normal.

The psychologist predicts that if the participant is paid a dollar for each letter identified correctly, the number correctly identified will increase to 74. The psychologist plans to test 20 participants under these conditions, using p < .05.

a.What is the power of this study?

b.Sketch the distributions involved, showing the area for alpha, beta, and power.