Which term identifies the probability of detecting a true effect when it exists?

The term that accurately identifies the probability of detecting a true effect when it exists is "power." In research, power refers to the likelihood that a study will correctly reject a null hypothesis when it is false, which means detecting an actual effect. High power is essential in ensuring that a study can identify significant effects, reducing the risks of Type II errors, which occur when a true effect is not detected.

Power is influenced by several factors, including the sample size, effect size, and significance level. As the sample size increases, for instance, the power of the test generally increases, making it more likely that a true effect will be detected if it is present. Understanding power is crucial for researchers as it helps in the design of studies, ensuring they are adequately equipped to identify the effects they are investigating.

In contrast to power, terms like error rate refer to the likelihood of making incorrect conclusions (either Type I or Type II errors), while the significance level (commonly set at 0.05) is the threshold for determining whether an observed effect is statistically significant. Beta, on the other hand, specifically refers to the probability of making a Type II error, which is the failure to reject a false null hypothesis; thus, it is inversely related