3. An investigator conducts a study to examine the benefits of psychotherapy for individuals with depression. Specifically, the investigator predicts that depressed individuals who receive psychotherapy in addition to drug therapy for depression will display significantly lower levels of depression than persons with a diagnosis of depression who receive only drug therapy. The investigator assigns 10 subjects to each of the two groups stated above. After three months the investigator measures depression using a scale in which higher scores reflect higher levels of depression. Psychotherapy plus drug therapy group: 23, 19, 16, 18, 15, 22, 16, 18, 19, 20 Drug therapy only: 24, 27, 26, 28, 29, 24, 26, 25, 22, 284. The mean productivity rating for all employees at a company was 3.8 on a five point scale last year. This year you get ratings from a representative sample of fifteen employees from the Human Research Management. Do the data from this sample provide evidence that employee productivity in the department of Human Resource Management is significantly higher than in the company as a whole? Scores: 4.1, 3.9, 3.5, 4.0, 4.4, 4.3, 4.2, 4.5, 3.9, 3.6, 4.2, 4.4, 4.1, 4.3, 4.2