PSY 550 Midterm Answers
Compare and contrast the following terms: (a) test-retest reliability with inter-rater reliability, (b) content validity with
... [Show More] both predictive validity and construct validity, and (c) internal validity with external validity.
Test-retest reliability and Inter-rater reliability:
Test-retest reliability measures the reliability of a test overtime and measures its consistency. For example, if we gave the same test twice to the same people, but at a different time, we could see if the scores are the same. We could test someone on a Tuesday and give the same test again on a Thursday. From there, we could correlate the test scores to one another. Inter-rater reliability is when we are looking at similarities in rating behaviors. This is when two or more raters view the same exact behavior and are in agreement with what the viewed. Both test-retest reliability and inter-rater reliability are forms of reliability. They both measure how stable a measure is over a period of time.
Content validity and both Predictive validity and Construct validity:
Content validity is when we determine is the correct item or test was used. For example, we are looking at if the test properly measures what we intended it to measure. This is different than both construct validity and predictive validity. Construct validity is whether the scale that was used in the test measures the construct correctly. While predictive validity is determining which scores obtained by a certain measurement predict the outcome that it should be predicting. Content validity, predictive validity, and construct validity are all measuring the validity of a particular measurement.
Internal validity and External validity:
Internal validity is the extent that we can manipulate a variable and cause a change to a dependent measure. If we have more control over a study, we have more internal validity. Internal validity also refers to the extent of where the experiment or study is free from errors. If any differences occur within the experiments, they are due to the independent variable and nothing else within the study. External validity is when an experiment or study can be related back to the world. External validity is applying the results outside the context of the study. It is when we can generalize results of the study to other people, times, and/or situations.
Use Stevens’ model of measurement scales to answer these questions:
1. What type of scale is used when the variable is social class? Explain.
2. What type of scale is used when the variable studied is a Top 40 list of popular songs? Explain.
3. What type of scale is used when the variable studied is intelligence scores (for example, on the Stanford-Binet-R)? Explain. [Show Less]