Related Experiment Video
Updated: Jun 12, 2026

Multimedia Battery for Assessment of Cognitive and Basic Skills in Mathematics (BM-PROMA)
Published on: August 28, 2021
Killeen's (2005) p rep coefficient: logical and mathematical problems
Michael Maraun1, Stephanie Gabriel
1Department of Psychology, Simon Fraser University, Burnaby, British Columbia, Canada. maraun@sfu.ca
Abstract:
In his article, "An alternative to null-hypothesis significance tests," Killeen (2005) urged the discipline to abandon the practice of p obs-based null hypothesis testing and to quantify the signal-to-noise characteristics of experimental outcomes with replication probabilities. He described the coefficient that he invented, prep, as the probability of obtaining "an effect of the same sign as that found in an original experiment" (Killeen, 2005, p. 346). The journal Psychological Science quickly came to encourage researchers to employ prep, rather than p obs, in the reporting of their experimental findings. In the current article, we (a) establish that Killeen's derivation of prep contains an error, the result of which is that prep is not, in fact, the probability that Killeen set out to derive; (b) establish that prep is not a replication probability of any kind but, rather, is a quasi-power coefficient; and (c) suggest that Killeen has mischaracterized both the relationship between replication probabilities and statistical inference, and the kinds of claims that are licensed by knowledge of the value assumed by the replication probability that he attempted to derive.
Related Concept Videos
Theorems of Pappus and Guldinus: Problem Solving
Mathematical Modeling: Problem Solving
Biot-Savart Law: Problem-Solving
Consider a mobile phone battery bank as a source of steady current, which flows through the wire connected between the two. What is the magnitude of the magnetic field created by this current at a field point P?
To estimate the magnitude of the total magnetic field, we first consider a small current element of length dl, at a distance r from the field point. Now the following...
Fundamental Theorem of Calculus I: Problem Solving
Castigliano's Theorem: Problem Solving
The Chain Rule: Problem Solving
