Statistical significance
Statistical significance In statistical hypothesis testing , [1] [2] a result has statistical significance when a result at least as "extreme" would be very infrequent if the null hypothesis were true. [3] More precisely, a study's defined significance level , denoted by � , is the probability of the study rejecting the null hypothesis, given that the null hypothesis is true; [4] and the p -value of a result, � , is the probability of obtaining a result at least as extreme, given that the null hypothesis is true. [5] The result is statistically significant, by the standards of the study, when � ≤ � . The significance level for a study is chosen before data collection, and is typically set to 5% [13] or much lower—depending on the field of study. [14] In any experiment or observation that involves drawing a sample from a populat...