0b-2. Sampling & Generalization

Multiple Choice

In this example, which group represents the POPULATION that I am interested in studying?

• All teenagers

• The students from my class that I select to ask about their favorite app

• The students in my AP Psychology class

• Everyone in this school

Multiple Choice

In the context of a research study, what is a sample?

• The entire group the researchers want to learn more about

• The subgroup of the population that is actually going to be studied in the research

• The method used to collect data

• The results of the research

Multiple Choice

Which of the following is the best explanation of what randomness means when it comes to selecting a sample from the larger population?

• Every member of the population has an equal chance of being selected

• The sample includes people from different subgroups in the population

• Participants are selected in a casual manner

• The sample contains only people who volunteered to participate

Multiple Select

Which of the following are methods to achieve random selection in sampling?

• Drawing names out of a hat

• Focusing on people who are physically near by

• Using a random number generator

• Asking people you know will agree to participate

Multiple Choice

Which sample is representative of the population shown at the top of the image?

• Sample A

• Sample B

Multiple Choice

Why is it important for a sample to be representative of the population in research studies?

• Because it guarantees that every individual in the population will eventually be studied

• Because it makes the research process faster and easier to complete

• Because it allows the researcher to avoid using random selection methods

• Because it ensures the findings can accurately reflect the larger group

Sampling bias

Ideally, researchers are always able to do their research on a sample of people who accurately represent the larger population they are interested in learning about.

But sometimes that is too difficult or costly.

Multiple Choice

Which of the following is NOT an example of convenience sampling?

• Giving surveys to whoever happens to be in the library after school

• Giving surveys only to students who are in your AP Psych class

• Giving surveys to students selected from the entire school roster using a random number generator

Multiple Choice

What is a major risk of using convenience sampling?

• It is time-consuming

• It is expensive

• Ending up with sampling bias

• It always produces a representative sample

Multiple Choice

Hank is writing an article for the school paper about how much time students in his school spend doing homework each night. So he asks the students in his AP Language class to fill out a chart each night for a week, adding up how much time they spend doing homework for all their classes.

What is the population that Hank is interested in learning about?

• Students taking AP Language

• Students who read the school newspaper

• Students at his high school

• Students who do their homework

Multiple Choice

Hank is writing an article for the school paper about how much time students in his school spend doing homework each night. So he asks the students in his AP Language class to fill out a chart each night for a week, adding up how much time they spend doing homework for all their classes.

Why is Hank's sampling strategy going to result in sampling bias?

• Because Hank did not include every student in the school in his study

• Because many students don't take AP classes, so this group of students is not representative of all students.

• Because students might give dishonest answers to avoid looking lazy

• Because students may not remember exactly how much time they spend on homework each night

Multiple Choice

Which of the following best describes the concept of generalizability in research?

• The process of making sure each subgroup in a population is proportionally represented in a sample.

• The extent to which research findings can be applied to people or situations beyond those specifically studied.

• The ability to measure variables in a way that produces consistent results over time.

• The tendency for participants to change their behavior because they know they are being observed.

Analyzing "generalizability"

A part of the AP Psych exam will ask you to "explain the extent to which the research findings [of a particular study that you are reading about] may or may not be generalizable.

To answer this question, you need to identify who was included in the study's sample, and who was left out.

Multiple Select

Which of the following were included as part of the sample in the mindfulness meditation research example?

• Pre-med students from an elite university

• Students who self-reported test anxiety

• Community college students

• Young children

Multiple Select

Which of the following were not included as part of the sample in the mindfulness meditation research example?

• English majors

• Students who attend an elite university

• Elderly people

• Students who do not have test anxiety

The next slide gives an example answer to the College Board's question: "Explain the extent to which the research findings may or may not be generalizable."

You will need to be able to write answers like this when given a description of the people who are part of the sample in a research study. As you read the next few slides, consider these answers to be models/examples for you.

Here is another example

Multiple Choice

In the birth order research example, which group was excluded from the study?

• Students with step-siblings or half-siblings

• Firstborn children

• Students aged 18-22

• Female students

And another example

Multiple Choice

Based on the research example, which of the following groups was NOT included in the study sample?

• Teens from lower-income families

• High school students aged 14-17

• Students from middle to upper-middle class families

• Students who used smartphones within 30 minutes of bedtime

Now you try one
(do your best with what you just learned - we'll work on this many more times this year!)

Open Ended

Research example: Researchers surveyed 200 middle school students (ages 11–13) from suburban schools in Texas about their daily screen time and social skills. All students attended private schools where tuition exceeds $20,000 per year. Students completed self-report questionnaires on how many hours they spent on screens per day and participated in a peer-rating activity on cooperation and friendliness. Results showed that students who reported more than 4 hours of daily screen time received significantly lower peer ratings of cooperation than students who reported less than 2 hours of screen time.

Explain the extent to which the research findings may or may not be generalizable: