EDCP 652 - Chapter 9 - Experimental Research Designs
Which of the following is a serious threat to the internal validity of the nonequivalent-groups posttest-only design?
Without a pretest, it is difficult to control for selection differences.
What is the major weakness of the single-group posttest-only design?
It is difficult to determine if the treatment or something else is responsible for the change in the participants' behavior.
Which of the following is a true statement about single-group pretest-posttest design?
The design will have more potential threats to internal validity as the time between pretest and posttest increases.
A study has strong external validity if which of the following is true?
The findings can be generalized to other participants and settings.
In experimental research, the researcher tries to keep which variable constant?
The independent variable
An experimental study has strong internal validity if which of the following is true?
The independent variable alone can account for the results.
Dr. Allen used a factorial design to investigate the effects of using supplemental Power Point presentations on males and females regarding their mastery of course objectives. Which of the following effects can be examined?
All of the above: A. Main effect for instructional strategy B. Main effect for gender C. Interaction effect for instructional strategy and gender
Which of the following is a potential threat to external validity?
Characteristics of the setting in which the information is collected
Factorial experimental studies are designed to enable researchers to do which of the following?
Determine if the effects are consistent across participant characteristics
Eighth graders in a control group were resentful of the treatment offered to their classmates in the intervention group. This is an example of which type of threat to internal validity?
Diffusion of intervention
An achievement test was used to collect data on a group of fourth-grade students. If a fire drill occurred in the middle the test, this would be an example of which type of threat to internal validity?
History
In experimental research, which of the following variables are controlled?
Independent and extraneous variables
In an experiment comparing the story writing abilities of two groups of fourth graders, two sets of scorers (one set for each group) were selected to evaluate the stories. What threat to internal validity has occurred?
Instrumentation
The extent to which the intervention, and not extraneous or confounding variables, produced the observed effect in an experimental study is related to what aspect of a study?
Internal validity
Natural changes in participants during the course of the experiment are what type of threat to internal validity?
Maturation
To assess the efficacy of the new math curriculum, Ms. Jackson conducted a small experiment using two of her four sixth-grade math classes. She gave both classes a pretest, then taught Class A using the new curriculum and continued using the old curriculum with Class B. At the end of three months she administered a posttest to both classes. Which design did Ms. Jackson use in her experiment?
Nonequivalent-groups pretest-posttest
Ninth graders in a study changed their behavior simply because they were aware they were participants in a research study. This is an example of which type of threat to internal validity?
Participant effects
Which of the following is NOT a potential threat to external validity?
Random assignment of participants to treatments
A researcher studied the comparative efficacy of two methods for teaching the metric system to sixth graders. The researcher assigned Method A to the honors math class and Method B to the regular math class. What threat to internal validity has occurred?
Selection
A study compared the results from an experiment. Participants in the treatment group were selected from a private school with strong parental support and participants in the control group were selected from a public school without strong parental support. This is an example of which type of threat to internal validity?
Selection
Mr. Ramsey had a serious concern about a study that concluded that cooperative group instruction was effective for all secondary students even though there were very few female students in the experimental group and a majority of the participants were female in the control group. Which of the following terms describes Mr. Ramsey's concern?
Selection
Nonrandom assignment to treatments is what type of threat to internal validity?
Selection
What is a major internal validity concern in a nonequivalent-groups pretest-posttest design?
Selection
Which of the following is NOT a threat to internal validity in the randomized-groups posttest-only and the randomized-groups pretest-posttest designs?
Selection
A teacher wanted to evaluate the efficacy of a new technique for teaching comprehension skills to her class of learning disabled students. She administered a comprehension test before introducing the new technique. At the end of the semester, she administered the test again and compared the results from the two tests. This study is an example of which of the following?
Single-group pretest-posttest design
Which of the following is NOT a characteristic of a true experimental design?
Stronger external validity
Which of the following criteria is NOT used to evaluate a single-subject research study?
The results are generalizable.
Which of the following is a criterion for determining the extent to which experimental research has strong external validity?
The results can be generalized to other individuals, measures, procedures, or settings.
Which of the following is a true statement about the single-group pretest-posttest design?
There are more potential threats to internal validity as the time between pretest and posttest increases.
