A researcher's decision regarding whether to reject the null hypothesis is based on:
A) the researcher's a priori theory regarding expected group differences.
B) independent confirmation by researchers in other laboratories.
C) the probability that group differences would be observed if there was no effect of the independent variable.
D) whether the results of the study have been replicated at least once.

Question

Quizplus · Accepted Answer

The decision to reject the null hypothesis is based on the probability that group differences would be observed if there was no effect of the independent variable. This probability is calculated through statistical tests such as p-values or confidence intervals. A researcher's a priori theory regarding expected group differences may inform the hypothesis and predictions for the study, but it is not the sole basis for determining whether to reject the null hypothesis. Independent confirmation by researchers in other laboratories and replication of results are important for establishing the validity and generalizability of findings, but they do not directly determine whether to reject the null hypothesis in a specific study.

A Researcher's Decision Regarding Whether to Reject the Null Hypothesis