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

RESEARCH STUDY 7.2: Dr.Parrett is a sports psychologist for a large Southern university.The provost and chancellor have asked him to examine the relationship between athletic performance and academic stress at the university.For example, is it the case that the most talented athletes experience the greatest concern over their grades? The provost and chancellor have made it clear to Dr.Parrett that they want a large amount of external validity in the study.He has valid and reliable measures of both athletic performance and academic stress.He knows that he does not have the time or the money to study the entire population of interest. What is the population of interest in Dr.Parrett's study? Will he be collecting a sample or conducting a census? Why does he need to be concerned with external validity/representativeness?

A sample is always a population.

Which of the following does NOT result in a representative sample?

Research articles that use terms such as "unbiased sample," "random samples," or "representative sample" allow for readers to .

RESEARCH STUDY 7.2: Dr.Parrett is a sports psychologist for a large Southern university.The provost and chancellor have asked him to examine the relationship between athletic performance and academic stress at the university.For example, is it the case that the most talented athletes experience the greatest concern over their grades? The provost and chancellor have made it clear to Dr.Parrett that they want a large amount of external validity in the study.He has valid and reliable measures of both athletic performance and academic stress.He knows that he does not have the time or the money to study the entire population of interest. Imagine that Dr.Parrett wants to use a nonrepresentative sampling technique.Name the three types of nonprobability sampling and explain how each one could be used by Dr.Parrett.

For his research methods class project, Hiro is studying the effect of pet ownership on stress levels.Although a lot of research has been done on dog and cat owners, not much is known about other pets so Hiro decides to study bird owners.Which of the following would demonstrate a snowball sampling technique?

What is the difference between random sampling and random assignment?

Which of the following is true of probability sampling?

Dr.Cyril conducts a simple random sample of 500 men who became fathers for the first time in the past year.He finds that 23% of them report being unsure of their ability to be good fathers, plus or minus 4%.If Dr.Cyril increased his sample size to 1,000, which of the following would happen?

Which of the following sampling techniques would you recommend to a researcher interested in studying rare individuals, like people who have been struck by lightning?

Why is the use of representative samples especially important in frequency claims?

What is the most common sampling technique in behavioral research?

RESEARCH STUDY 7.1: Professor Kramer has decided to measure how happy his students are with his teaching this semester.He is teaching two classes this semester-Psychology and Law and Introduction to Neuroscience.He gives his students a survey. Dr.Kramer plans to give his survey only to his Psychology and Law students because he sees them on Mondays, Wednesdays, and Fridays and he can spare the class time (unlike in his Introduction to Neuroscience class, which only meets on Tuesdays and Thursdays).Which of the following is true?

RESEARCH STUDY 7.3: 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. Name two populations of interest that Dr.Dowling could reasonably generalize her findings to.State which of these two populations her findings would be more generalizable to and explain why that is the case.

Explain why bigger samples are not always better samples.

Which of the following statements is true of random assignment and random sampling?

Studies that use nonprobability samples have external validity.

Which of the following is necessary for a sample to be considered representative?

If a sample is biased, then it is the population of interest.

Online surveys commonly suffer from which of the following?