LSP Research Methods & Statistics 2 — Questions and Answers
Question 1: What is effect size and why is it important beyond p-values?
- A measure of the magnitude of a treatment effect or relationship, indicating practical significance beyond statistical significance (Correct answer)
- A measure of sample size
- The number of variables in a study
- The cost of conducting research
Correct answer: A measure of the magnitude of a treatment effect or relationship, indicating practical significance beyond statistical significance
While p-values indicate whether an effect exists, effect sizes (like Cohen's d or r) tell you how large the effect is. A statistically significant result can have a trivially small effect size with a large enough sample.
Question 2: What is a control group in experimental research?
- A group that does not receive the experimental treatment, serving as a baseline for comparison (Correct answer)
- The group that controls the experiment
- The largest group in the study
- A group of researchers overseeing the study
Correct answer: A group that does not receive the experimental treatment, serving as a baseline for comparison
The control group provides a baseline against which the experimental group's outcomes are compared, allowing researchers to attribute differences to the independent variable rather than extraneous factors.
Question 3: What is internal validity in research?
- The degree to which an experiment demonstrates that the independent variable caused changes in the dependent variable (Correct answer)
- The validity of the measures used in the study
- How well results generalize to other settings
- The statistical power of the analysis
Correct answer: The degree to which an experiment demonstrates that the independent variable caused changes in the dependent variable
Internal validity reflects confidence that observed effects are truly caused by the independent variable and not by confounding variables, measurement error, or other threats to the experimental design.
Question 4: What is the difference between qualitative and quantitative research?
- Quantitative uses numerical data and statistical analysis; qualitative uses non-numerical data like interviews and observations to understand experiences (Correct answer)
- Quantitative is always better than qualitative
- Qualitative research uses larger samples
- They cannot be combined in the same study
Correct answer: Quantitative uses numerical data and statistical analysis; qualitative uses non-numerical data like interviews and observations to understand experiences
Quantitative research tests hypotheses using numerical data and statistics. Qualitative research explores phenomena in depth through interviews, observations, and thematic analysis, providing rich contextual understanding.
Question 5: What is the APA's ethical requirement regarding deception in research?
- Deception is permitted only when no alternative exists, the study has significant value, and participants are debriefed as soon as possible (Correct answer)
- Deception is never permitted in psychological research
- Deception is always acceptable if the researcher believes it is necessary
- Only verbal deception is prohibited
Correct answer: Deception is permitted only when no alternative exists, the study has significant value, and participants are debriefed as soon as possible
APA ethics allow deception only when the study cannot be conducted otherwise, the potential findings justify it, participants are not deceived about significant risks, and thorough debriefing occurs afterward.
Question 6: What is a longitudinal study design?
- A study that follows the same participants over an extended period to observe changes over time (Correct answer)
- A study conducted in a long room
- A study with a very large sample
- A study that takes a long time to analyze
Correct answer: A study that follows the same participants over an extended period to observe changes over time
Longitudinal studies collect data from the same participants at multiple time points, allowing researchers to study developmental changes, long-term outcomes, and causal relationships that cross-sectional designs cannot capture.
LSP Research Methods & Statistics 2
What is effect size and why is it important beyond p-values?