Psychology advances knowledge by testing statistical hypotheses using empirical
observations and data. The expectation is that most statistically significant findings can be …

Structural equation modeling (SEM) is a widespread approach to test substantive
hypotheses in psychology and other social sciences. However, most studies involving …

The sample size necessary to obtain a desired level of statistical power depends in part on
the population value of the effect size, which is, by definition, unknown. A common approach …

Concerns about the veracity of psychological research have been growing. Many findings in
psychological science are based on studies with insufficient statistical power and …

When designing a study, the planned sample size is often based on power analyses. One
way to choose an effect size for power analyses is by relying on pilot data. A-priori power …

Background Sample size planning for longitudinal data is crucial when designing mediation
studies because sufficient statistical power is not only required in grant applications and …

Repeated investigations of the same phenomenon typically yield effect sizes that vary more
than one would expect from sampling error alone. Such variation is even found in exact …

Within an extended challenge–hindrance framework, it is assumed that job demands are
subjectively appraised both as challenges (that is, as working conditions that are associated …

In the current psychological debate, low replicability of psychological findings is a central
topic. While the discussion about the replication crisis has a huge impact on psychological …

Intensive longitudinal research designs are increasingly used to study personality
processes. The resulting data can be highly informative in ways that other data cannot, but …