18 Questions
Which of the following is a potential cause of not enough between-groups difference in a study?
Measurement error
Which of the following is a potential cause of too much within-groups variability in a study?
Measurement error
Which of the following can help counteract the problem of not enough between-groups difference in a study?
Multiple measurements
Which of the following can help counteract the problem of too much within-groups variability in a study?
Irrelevant individual differences
If a study has avoided all obscuring factors, what can it provide?
Valuable evidence
What should you do with a study that provides valuable evidence?
Consider it along with other studies on the same topic
Which of the following can help counteract the problem of not enough between-groups difference in a study?
Design confound acting in reverse
Which of the following can help counteract the problem of too much within-groups variability in a study?
Weak manipulations
What can you do to evaluate how strong some effect is in the real world?
Consider multiple studies on the same topic
Which of the following is NOT a threat to internal validity in an experiment?
Regression
Which of the following is a potential threat to internal validity in a one-group, pretest/posttest design?
Maturation
Which of the following is NOT a potential threat to internal validity in any experiment?
Regression
If an experiment finds that an independent variable affected a dependent variable, what should be considered to determine internal validity?
All of the above
What can be concluded if a study has ruled out all twelve threats to internal validity?
The study has strong internal validity
What should you review if you encounter a study with a null effect?
Obscuring factors
Which of the following is NOT a category of obscuring factors?
Design confounds
Which of the following is a potential threat to internal validity in a pretest/posttest design?
Testing effects
What can be concluded if a study has ruled out all twelve threats to internal validity?
The study has strong internal validity
Study Notes
Study Design and Potential Errors
- Not enough between-groups difference in a study can be caused by low sample size, weak manipulations, or insensitive measures.
- Too much within-groups variability in a study can be caused by individual differences, measurement error, or extraneous variables.
Counteracting Errors
- Increasing the sample size, using stronger manipulations, or using more sensitive measures can help counteract the problem of not enough between-groups difference in a study.
- Using a more homogeneous sample, controlling for extraneous variables, or using more reliable measures can help counteract the problem of too much within-groups variability in a study.
Evaluating Study Evidence
- A study that has avoided all obscuring factors can provide convincing evidence for a cause-and-effect relationship.
- If a study provides valuable evidence, it should be replicated and reviewed to ensure the findings are reliable.
Evaluating Study Results
- To evaluate how strong some effect is in the real world, you can consider the size of the effect, the consistency of the results, and the generalizability of the findings.
Threats to Internal Validity
- Maturation is NOT a threat to internal validity in an experiment.
- History and testing are potential threats to internal validity in a one-group, pretest/posttest design.
- Demographic differences are NOT a potential threat to internal validity in any experiment.
- If an experiment finds that an independent variable affected a dependent variable, alternative explanations, such as history, maturation, and selection, should be considered to determine internal validity.
Conclusion and Review
- If a study has ruled out all twelve threats to internal validity, it can be concluded that the observed effect is likely due to the independent variable.
- If a study has a null effect, the sample size, measurement error, and experimental design should be reviewed.
- Demographic differences are NOT a category of obscuring factors.
- History and testing are potential threats to internal validity in a pretest/posttest design.
- If a study has ruled out all twelve threats to internal validity, it can be concluded that the observed effect is likely due to the independent variable.
Test your knowledge on threats to internal validity in experiments with this quiz. Learn about the factors that can impact the relationship between an independent variable and a dependent variable, and how to increase a study's power to avoid false null effects.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
