In effect size calculations, what does a larger effect size indicate?

A larger effect size indicates a stronger relationship or greater impact of a phenomenon because it quantifies the magnitude of the difference or relationship being studied. Effect size provides insight beyond mere statistical significance; it reflects how meaningful the findings are in practical terms.

For instance, in the context of a psychological study, a large effect size suggests that the intervention or variable has a substantial and noticeable influence on the outcomes, which can be critical for evaluating the effectiveness of treatments or interventions. This measurement is particularly valuable when comparing studies or interventions, as a large effect size can suggest that the results are not only statistically significant but also important in real-world applications.

In contrast, options referring to significance, weakness, or hypothesis failure do not convey the direct implication of effect size, which specifically emphasizes the strength or impact of the observed phenomenon rather than its statistical or theoretical standing.