Correlational Research: Surveys Remember that April 3 is a hard deadline for all work through Unit 5. No late work will be accepted after April 3.

Correlation The degree to which two variables are related.

Sampling

Sampling Methods In probability sampling all members of a population have an equal chance of being included in the sample. Simple random sampling is the basic technique of probability sampling. The most common definition of simple random sampling is that every member of the population has an equal chance of being included in the sample. In stratified random sampling, the population is divided into subpopulations called strata (singular, stratum), and random samples are drawn from each of these strata. First, select your population.

Survey Research Designs: Sampling

Reliability Reliability = consistency, each time Reliability: Definition The degree of consistency between two measures of the same thing The measure of how stable, dependable, trustworthy, and consistent a test is in measuring the same thing each time. Think of this like a job. You want an employee who is going to show up for work every day. They are dependable. For example, if we wish to measure a person's weight, we would hope that the scale would register the same measure each time the person stepped on the scale.

Reliability test-retest reliability = giving the same test to a group of people at different times internal consistency reliability = multiple items on one test measure the same thing

Validity Validity = measuring what it is supposed to measure Truthfulness: Does the test measure what it purports to measure? The degree to which they accomplish the purpose for which they are being used. Think of this like a job. You want an employee who is not only going to show up for work every day (reliability) but you want them to also do the job they are supposed to do. For a test to be valid, or truthful, it must first be reliable. If we cannot even get a bathroom scale to give us a consistent weight measure, we certainly cannot expect it to be accurate. Note, however, that a measure might be consistent (reliable) but not accurate (valid). A scale may record weights as two pounds too heavy each time.

Validity Note that convergent = correlates well with, divergent = correlates poorly with construct validity is determined by assessing both convergent validity and discriminant validity

Question 1 Describe the importance of obtaining a representative sample when conducting survey research. Make sure to discuss the different methods of sampling that are described in the text, namely: cross-sectional successive independent samples Longitudinal simple random sampling stratified random sampling What are the pros and cons of each of these different sampling methods? How do these sampling methods influence the conclusions that can be made?

Question 2 Discuss the different types of reliability and validity that can be measured in survey research, specifically: convergent validity discriminant validity construct validity test-retest reliability internal consistency reliability What can researchers do to improve upon these different types of reliability and validity in a survey?

Seminar Think about some of the different methods of survey research that you have encountered in your own life like mail surveys, telephone surveys, or internet surveys. Do specific demographic groups respond differently to these methods? For example, women, retirees, students, African Americans? Why? How does the sample influence the conclusions that you can make? Finally, how does social desirability influence the results? What can researchers do to prevent this issue?

And always remember …. I am here to support you through this course. I want you to enjoy this course and do well. Let me know if you have any questions or problems.