Exam 9: Sampling and Introduction to External Validity

A researcher is interested in road rage and wants to study commuters' driving behavior in different parts of the United States. She examines driving behavior in the North, South, East, and West. These geographical regions are examples of:

The text provides a guideline that there should be a minimum of 30 participants per major group in a sample.

Ecological validity ratings are based on:

It is possible for the theoretical and accessible populations to be the same group of participants.

Match the following examples with their appropriate concepts -Tom Hanks did a gumbo-eating study in New Orleans. As the tester, he had a good rapport with the people he interviewed in the city's gumbo restaurants.

Questionnaires and surveys are generally considered to have medium ecological validity.

Match the following examples with their appropriate concepts -A student from Brazil decided to study American Super Bowl enthusiasm. She gave a questionnaire to a group of retired kindergarten teachers at their annual potluck reunion.

High experimental mortality for certain groups and not for others can produce a nonrepresentative sample.

There is medium population validity when the researcher makes some attempt to obtain a good sample.

Describe the differences between the theoretical or target population, the accessible population, the selected sample, and the actual sample.

With a simple random probability sample, the descriptive statistics also describe the population.

A researcher is investigating the use of homeopathic remedies among different socio-economic groups. She has to over-sample Native Americans from her accessible population in order to obtain a representative sample. This is an example of what type of sampling technique:

Representativeness is a more important consideration than sample size.

Match the following examples with their appropriate concepts: -Jill wants to study 10 people from a population of 100. She has a list of everybody's names and randomly picks numbers 52, 38, 17, 90, 41, 3, 78, 12, 1, 66.

Aspects of a study that may result in an unrepresentative sample include:

A researcher is interested in the number of college administrators in the United States who are Asian women. Match the following concepts with the examples provided: -A return of 45 out of 100 questionnaires.

Match the following examples with their appropriate concepts: -Judy wants to study a population of new college students, N=100. She wants to study 10 students. She randomly picks a number between 1 and 10. Let's say 3. Starting with the 3^rd person on her list, she samples every 10^th person (3^rd, 13^th, 23^rd, etc.).

In your own words, define external validity.

A convenience sample attempts to select participants who are representative of the accessible population.

Match the following examples with their appropriate concepts: -Rudy recruits sophomore college students from 4 accessible universities for a leadership study.