Exam 9: Experimental Designs: Within-Subjects Design

Counterbalancing effectively eliminates order effects.

What does counterbalancing involve?

The tendency for extremely high scores on one measurement to be followed by lower scores on a second measurement is called statistical regression.

A researcher is evaluating the changes in performance that occur during a six-week training program. Participants are observed at the beginning and at the end of the program and the researcher rates each individual's level of performance. When the researcher's standards for rating performance change from the first observation to the last, then the internal validity of the study is threatened by ____.

The tendency for individuals who have extreme scores (high or low) on one measurement and to have less extreme scores on a second measurement is called ____.

When one treatment condition has a lasting effect on individuals and influences their scores in future treatments, the study is confounded by ____.

Outline the major advantages and disadvantages of using a two-treatment design and a multiple-treatment design.

For an experiment comparing two treatment conditions, there will be ____ score(s) for each participant if a within-subjects design is used and there will be ____ score(s) for each participant if a between-subjects design is used.

A matched-subjects design attempts to eliminate the problems associated with ____ that are a concern for between-subjects designs and also eliminate the problems associated with ____ that are a concern for within-subjects designs.

The most appropriate hypothesis test for a within-subjects design that compares three treatment conditions is a(n) ____.

During the first treatment condition of a within-subjects experiment, the participants learn a new skill that helps improve their performance in later treatment conditions. For this study, the internal validity is threatened by ____.

Under what circumstances is a within-subjects design NOT a good choice for a research study?

Describe the process of counterbalancing and explain how this process reduces the risk of problems from order effects.

Explain what partial counterbalancing is and when it would be used in a within-subjects study.

For an experiment that compares two treatment conditions with ten scores in each treatment, which design would require the smallest number of participants?

Order effects can become a confounding variable because ____.

In a within-subjects study that extends over a relatively long time, it is possible that there will be systematic changes in the participants' skills or knowledge during the time of the study. When these changes influence the participants' scores, causing scores at the end of the study to be different from scores at the beginning, the effect is called ____.

For a within-subjects experiment, one advantage of a two-treatment design compared to a multiple-treatment design is that it is easier to counterbalance.

A Latin square is used with _____.

Partial counterbalancing for four treatments would require four groups of participants.