Free Psychology Degree Psychological Research Methods Questions and Answers — Questions and Answers
Question 1: A researcher wants to test the effect of a new mindfulness app on anxiety levels. They randomly assign participants to two groups: one uses the app for 15 minutes daily, and the other does not. They measure anxiety levels before and after the two-week period. What is the independent variable in this study?
- The final anxiety levels of the participants.
- The two-week duration of the study.
- The use of the mindfulness app. (Correct answer)
- The initial anxiety levels of the participants.
Correct answer: The use of the mindfulness app.
The independent variable is the factor that the researcher manipulates to observe its effect on another variable. In this experiment, the researcher is directly controlling whether or not participants use the mindfulness app, making it the cause being investigated.
Question 2: Which of the following is the most significant threat to the internal validity of a quasi-experimental design?
- The difficulty in operationalizing the dependent variable.
- The absence of random assignment to conditions. (Correct answer)
- Low statistical power to detect an effect.
- The inability to generalize findings to a larger population.
Correct answer: The absence of random assignment to conditions.
Internal validity is the extent to which a study can claim a causal relationship. Quasi-experiments, by definition, lack random assignment. This means pre-existing differences between the groups could account for any observed effects, creating a major threat to internal validity that a true experiment with random assignment would control for.
Question 3: A psychologist develops a new 10-item questionnaire to measure self-esteem. They administer it to the same group of individuals on two separate occasions, one month apart, and then calculate the correlation between the two sets of scores. This procedure is an example of assessing which type of reliability?
- Inter-rater reliability
- Internal consistency
- Test-retest reliability (Correct answer)
- Split-half reliability
Correct answer: Test-retest reliability
Test-retest reliability assesses the consistency and stability of a measure over time. By administering the same test to the same people at two different points and finding a high correlation, the researcher demonstrates that the questionnaire produces stable results, assuming the underlying construct (self-esteem) has not changed.
Question 4: In inferential statistics, what does a p-value represent?
- The probability of obtaining the observed results, or more extreme results, if the null hypothesis were true. (Correct answer)
- The probability that the research hypothesis is true.
- The size of the effect of the independent variable on the dependent variable.
- The probability that the results were obtained due to random sampling error.
Correct answer: The probability of obtaining the observed results, or more extreme results, if the null hypothesis were true.
The p-value is a measure of statistical significance that quantifies the probability of observing the collected data (or more extreme data) under the assumption that there is no real effect or difference (the null hypothesis). A small p-value suggests that the observed results are unlikely if the null hypothesis is true, leading researchers to reject it.
Question 5: A researcher is conducting a study on the effects of sleep deprivation on cognitive performance. Participants are required to stay awake for 36 hours in a controlled lab setting. According to APA ethical guidelines, what is the MOST crucial step the researcher must take before the study begins?
- Provide a full debriefing of the study's true purpose.
- Obtain approval from the university's financial department.
- Securely store the data using encryption.
- Obtain informed consent from all participants. (Correct answer)
Correct answer: Obtain informed consent from all participants.
The APA ethical principle of informed consent mandates that participants must be fully informed about the research purpose, procedures, potential risks (like those from sleep deprivation), benefits, and their right to withdraw at any time before they agree to participate. This is the most critical initial step to ensure participant autonomy and welfare.
Question 6: An investigator observes children on a playground and records the frequency of aggressive behaviors. To prevent their own expectations from influencing how they interpret and record the behaviors, they use a detailed checklist of specific actions (e.g., 'pushes another child,' 'takes a toy without asking'). This strategy is primarily intended to minimize which type of bias?
- Observer bias (Correct answer)
- Sampling bias
- The placebo effect
- Demand characteristics
Correct answer: Observer bias
Observer bias occurs when a researcher's expectations or personal beliefs unintentionally influence their observations or recordings. Using a clear, objective checklist with operational definitions for behaviors helps to standardize the data collection process and reduces the potential for subjective interpretations to skew the results.
Free Psychology Degree Psychological Research Methods Questions and Answers
A researcher wants to test the effect of a new mindfulness app on anxiety levels.
They randomly assign participants to two groups: one uses the app for 15 minutes daily, and the other does not.
They measure anxiety levels before and after the two-week period.
What is the independent variable in this study?