A Social Worker Decided That His Clients Lacked an Important $\Sigma$

A social worker decided that his clients lacked an important skill-assertiveness. He spent the next eight weeks teaching assertiveness during group sessions. A psychologist friend of his suggested that he determine whether the training was successful by testing his group on the Door Manifest Assertiveness Test, which has a population mean of 30. The 16 clients took the test, and the statistics that follow were obtained. Use a 95 percent confidence interval to analyze the data. Describe the results of this study in terms understandable to the social worker's supervisor.N = 16 $\Sigma$ X² = 19, 020 $\Sigma$ X = 544