From each description, identify or infer the target population, the sampling frame, the unit of analysis, and the type of sample. Discuss whether the sampling strategy will allow the researcher to form inferences about the target population based on the sample.

a) Problem: To study factors related to a diagnosis of depression in elderly individuals. Sample: A random selection of 150 of the 300 residents diagnosed with depression in one year while in a particular geriatric facility and 340 randomly selected from the 850 residents in the same facility who were not diagnosed with depression during that year.

b) Problem: To obtain information on routes and types of transportation used by people traveling with the city. Sample: The Council of Governments has a computerized dataset of 110,000 trips made in one year; 10 percent of the trips are randomly selected for intensive analysis.

c) Problem: To see whether employees changed behavior after attending a training program. Sample: Randomly selected five training sessions held in 2003, identified the trainees in the selected sessions, and compared performance reviews of the trainees recorded before the sessions with those developed after.

d) Problem: To determine the effects of a change in publisher on a newspaper. Sample: Randomly selected seven U.S. cities and identified and studied all newspapers published in these cities over the past century.

e) Problem: To determine the total amount of assistance received by welfare clients. Sample: Thirteen states that represented geographic regions and a full range of payments were selected. One to three counties within a metropolitan statistical area within each of these states were selected. In each selected county, the welfare director gathered data on each of the first 50 clients coming in to recertify eligibility for benefits.