In this course, we will explore the so‐called “reproducibility crisis” that has struck fields from psychology and economics to ecology and cancer biology. You will learn statistical principles at the heart of the reproducibility crisis, how disregard …
Newly discovered true (non-null) associations often have inflated effects compared with the true effect sizes. I discuss here the main reasons for this inflation. First, theoretical considerations prove that when true discovery is claimed based on …
Does psi exist? D. J. Bem (2011) conducted 9 studies with over 1,000 participants in an attempt to demonstrate that future events retroactively affect people's responses. Here we discuss several limitations of Bem's experiments on psi; in particular, …
Null hypothesis testing of correlational predictions from weak substantive theories in soft psychology is subject to the influence of ten obfuscating factors whose effects are usually (1) sizeable, (2) opposed, (3) variable, and (4) unknown. The net …
Researchers should be motivated to adequately power statistical tests because tests with low power have a low probability of detecting true effects. However, it is also often claimed that significant results obtained by underpowered tests are less …
Psychology is working on the hardest problems in all of science. Physics, astronomy, geology — those are easy, by comparison. Understanding consciousness, willpower, ideology, social change – there’s a larger-than-Large-Hadron-Collider level of …