The obtained value of t, for a correlated samples t test, is 2.201, on 12 degrees of freedom. This is significant at the .05 level, two-tailed.

Dr. Clark works in a hospital where she studies and treats mental disorders. Earlier she had a patient with major depression and she prescribed an antidepressant for him. Identify Dr. Clark's profession.

A. clinical psychologist B. social worker C. psychiatrist D. mental health counselor

Dr. Irwin is testing the same individuals repeatedly over time as part of a research study, whereas Dr. Jenner is comparing the performance of different people of various ages at the same time

Dr. Irwin is using a _________ research design; Dr. Jenner is using a ________ design. a) cross-sectional; longitudinal b) longitudinal; cross-sectional c) longitudinal; simultaneous d) sequential; cross-sectional