Introduction What does it mean to say that someone is tall or short or to say that a person’s cholesterol level is high or low? Relative descriptions such as these only have meaning because an individual is being compared to a reference group. An American woman with a height of 70 inches might be considered tall because she is being compared to other American women. A man with the same height would be considered average if compared to other American men. If that same man were on a basketball team, he might be considered short.

Along the same lines, it is only meaningful to talk about high and low test scores when the scores are compared to a standard. A frequently used standard is the scores of a normative sample. This week, you explore characteristics of a good normative sample and examine how to address sampling considerations related to psychological tests.

Objectives Students will:

Analyze sampling considerations related to psychological tests Justify the use of sampling and data collection methods for psychological testing situations

Discussion 1: Sampling In order to compare individuals to a population, that population must be sampled using a standardization sample, also referred to as a norm group. This group represents the population for which a test is intended. There are a number of important considerations when choosing a test’s standardization sample, such as how large your sample needs to be and how you plan to access your participants and induce them to participate.

You may also need to consider whether the participants should be representative of the general population or of a specialized subpopulation and how diverse the sample should be. You may have general norms or separate norms according to demographic characteristics, such as age and gender. How to address these considerations depends on the goals of your assessment and will affect the test interpretation.

With these thoughts in mind:

1. Post an explanation of the THREE most important considerations related to sampling that you would need to address in your *Final Project.

2. Explain how you might ensure that your sample represents the population of interest.

Be sure to support your postings and responses with specific references to the Learning Resources.

Read a selection of your colleagues’ postings.

Than Respond to at least two of your colleagues’ postings in one or more of the following ways:

Ask a probing question. Share an insight from having read your colleague’s posting. Offer and support an opinion. Validate an idea with your own experience. Make a suggestion. Expand on your colleague’s posting.

Return to this Discussion in a few days to read the responses to your initial posting. Note what you have learned and/or any insights you have gained as a result of the comments your colleagues made.

Discussion 2: Optimizing Sampling and Data Collection The data that you collect from your norm group are called normative data. These data allow you to see what the results of your test instrument should be, so that you have a standardized score against which to compare others. In other words, the data allow you to equate scores across different tests of the same construct and let you compare individuals to each other.

Now that you have considered sampling the population of interest for your proposed test instrument, you explore how you might optimally define your sample and collect your data if you had unlimited resources. Although it may not always be possible for practical reasons to do this in real life, this exercise nevertheless provides you with a valuable thought experiment.

As you complete this experiment, keep in mind that even with optimal sample definition and data collection, test norms are not absolute. They can change with time or with a different norm group.

With these thoughts in mind:

1. Post a description of the information you anticipate collecting through your proposed Final Project instrument. 2. Then explain how you would optimally define your sample and collect your data if you had unlimited resources.

3. Finally, explain advantages and disadvantages of your chosen data collection method.

Support your response using the Learning Resources and the current literature.

Be sure to support your postings and responses with specific references to the Learning Resources.

Read a selection of your colleagues’ postings.

Than

Respond to at least two of your colleagues’ postings in one or more of the following ways:

Ask a probing question. Share an insight from having read your colleague’s posting. Offer and support an opinion. Validate an idea with your own experience. Make a suggestion. Expand on your colleague’s posting.

Readings

Kline, T. (2005). Psychological testing: A practical approach to design and evaluation. Thousand Oaks, CA: Sage.
Kline, T., Psychological testing: A practical approach to design and evaluation. Copyright 2005 Sage Publications Inc. Books. Used with permission from Sage Publications via the Copyright Clearance Center. Chapter 4, Collecting Data: Sampling and Screening” Buchanan, T., Ali, T., Heffernan, T. M., Ling, J., Parrott, A. C., Rodgers, J., & Scholey, A. B. (2005). Nonequivalence of on-line and paper-and-pencil psychological tests: The case of the prospective memory questionnaire. Behavior Research Methods, 37(1), 148154.
Retrieved from the Walden Library databases. Naglieri, J., Drasgow, F., Schmit, M., Handler, L., Prifitera, A., Margolis, A., & Velasquez, R. (2004). Psychological testing on the Internet: New problems, old issues. American Psychologist, 59(3), 150162.
Retrieved from the Walden Library databases.