Example of Distinguishing Correlational and Experimental Research

A researcher finds that people who drink more herbal tea tend to have lower stress levels. Which of the following explains why an experimental design is better suited than a correlational design for determining if the tea specifically causes the stress reduction?

A researcher finds a significant positive correlation ($r = .42$) between the amount of time people spend on social media and their self-reported levels of loneliness. True or False: This finding alone is sufficient to conclude that social media use causes an increase in loneliness because the relationship is statistically significant.

A researcher wants to evaluate the claim that 'regular physical exercise causes an improvement in cognitive function.' Rank the following research findings based on the strength of the evidence they provide for this causal claim, ordering them from the lowest degree of causal evidence (1) to the highest degree of causal evidence (3).

In psychology research, why is experimental research uniquely able to establish cause-and-effect claims while correlational research is not?

Match each research concept with the specific role it plays in the comparison between correlational and experimental methods in psychology.

Match each term to the description that best captures its role in whether a research design can establish causation.

While correlational research can identify relationships between variables, the only type of research that can establish cause-and-effect claims is _____ research.

A developmental psychologist observes that children who own more books at home earn higher scores on standardized reading assessments. Based solely on this finding, she concludes that book ownership causes improved reading ability. True or False: This causal conclusion is justified by the data.

A researcher randomly assigns half of a sample to a daily journaling condition and the other half to a no-journaling control condition, then measures stress levels after four weeks. The key feature that allows this study to make a causal claim—unlike a correlational study that simply observes an association between journaling and stress—is that the experimental design controls for _____, thereby isolating journaling as the direct cause of any observed change in stress.

A student reads a news headline: 'Study proves that listening to classical music causes better exam performance.' Order the following evaluation steps from first (1) to last (5) to properly judge whether this causal claim is justified.

Explain the fundamental difference between correlational and experimental research in their ability to establish causation. In your answer, recall the specific design feature that enables experimental research to support cause-and-effect claims.

Based on this scenario, diagnose why the psychologist cannot conclude that making daily to-do lists causes a reduction in stress. Then, explain what changes when transitioning to an experimental design, justifying how it would allow the researcher to support a cause-and-effect claim.

A researcher discovers a statistical correlation between students' regular physical exercise and their test scores. Apply your understanding of research methods to describe what design change the researcher must implement to establish that exercise causes better test scores, and state how this design change addresses alternative explanations.