The first thing any scientist does before performing an experiment is to form a hypothesis about the experiment's outcome. This often takes the form of a null hypothesis, which is a statistical ...

It may be common knowledge that p < .05 indicates statistical significance. Psychology students (and others) are often taught that p < .05 means the probability (p) of rejecting the null hypothesis ...

Confidence intervals are computed from a random sample and therefore they are also random. The long run behavior of a 95% confidence interval is such that we’d expect 95% of the confidence intervals ...

What is Fisher's exact test? Fisher’s exact test is a statistical hypothesis test used to assess the association between two binary variables in a contingency table and is particularly useful when ...

What is the chi-squared test? The chi-squared test, often written as χ 2 test, is a statistical hypothesis test used in the analysis of categorical variables to determine whether observed data are ...