Which of the following best describes the primary purpose of conducting a power analysis during the design phase of a study?

Match each term related to power analysis with the statement that best describes its role or definition in psychological research design.

Dr. Aris is designing a study on a new teaching method that she expects will produce a very small effect on student test scores. A power analysis will likely indicate that she needs a larger sample of participants to reliably detect this effect compared to a study looking for a much larger effect size.

Based on the logic of power analysis, arrange the following research scenarios in order from the one that would require the smallest sample size (Order 1) to the one that would require the largest sample size (Order 3).

At which stage of the research process is a power analysis typically performed by a researcher?

By identifying the specific number of participants needed to reliably detect an expected effect, a power analysis can help researchers avoid the inefficient use of resources that occurs when recruiting a larger sample than is statistically required.

A peer reviewer evaluates a research manuscript and critiques the authors for using a sample size of only $N = 20$, arguing it is likely too small to detect the hypothesized effect. To have justified their sample size and evaluated the design's adequacy during the planning phase, the authors should have conducted a(n) _____.

Match each research design scenario with its corresponding implication for conducting a power analysis to ensure statistical validity.

A researcher increases the number of experimental conditions in their study from two to five. To analyze how this change affects the likelihood of detecting a significant relationship, the researcher must calculate the new number of participants needed to maintain adequate statistical _____.

Order the following steps a researcher should take to evaluate and ensure the statistical validity of their study design, from the earliest planning step to the final analysis step.

Define what a power analysis is in the context of psychological research and identify the specific phase of a study during which researchers perform this calculation.

Based on the principles of statistical validity, what specific calculation must Dr. Lin conduct, and why does the number of experimental conditions in her study make this calculation critical?

A research team is concerned that their study lacks sufficient statistical power to test their hypothesis effectively because they added several new experimental conditions without recruiting additional participants. What specific calculation should they have performed during the design phase to avoid this problem by determining the exact number of participants they needed?