Abstract

The research provides evidence that null hypothesis significance testing (NHST) is frequently
misunderstood and, consequently, misused by researchers. Sources of these misunderstandings can be stated as: 1)
Interpreting NHST as a probability on accuracy of null hypothesis, 2) regarding NHST as an indicator of effect size,
and 3) overlooking the fact that NHST is just an analysis on means. This study investigates these misuses and
discusses confidence interval, effect size and noncentral probability distributions through their possible contributions
on resolving the misuses.

Key words: Hypothesis testing, confidence interval, effect size, noncentral probability distributions