Exam 7: Sampling: Estimating the Frequency of Behaviors and Beliefs

Which of the following is true of sample size?

How are quota sampling and stratified random sampling similar?

Dr. Tanaka is an educational psychologist interested in students' attitudes toward science and the effect of those attitudes on performance on standardized tests. He chooses his local school district to study. There are 15 high schools, and he randomly chooses five. Then, of the 2,500 students in each of those five schools, he randomly recruits 250 students. This is an example of which of the following sampling techniques?

Dr. Dowling is a clinical psychologist who is interested in the link between mental illness and criminal activity. She gets IRB permission to study patients at all five inpatient/residential mental health facilities in her state. There are 4,307 patients currently living in these facilities. She asks patients whether they have ever been arrested for a crime and whether they have ever been convicted of a crime. She collects a sample size of 1,369. She finds that 27% (+/− 3%) report having been arrested for a crime but that only 13% (+/− 3%) have been convicted of a crime. Dr. Dowling is interviewed by a journalist about the findings of her study. The journalist asks Dr. Dowling how many people live in all five hospitals and Dr. Dowling answers. The journalist replies that given that there are only about 4,000 people, it seems reasonable that Dr. Dowling should have studied the entire population rather than just drawing a sample for her study to really tell us something about people suffering from mental illness. How should Dr. Dowling respond?

A sample is to as a population is to .