Significance value

The significance value, or p value, is the probability that a result occurred by chance. The significance value is compared to a predetermined cutoff (the significance level) to determine whether a test is statistically significant. If the significance value is less than the significance level (by default, 0.05), the test is judged to be statistically significant.

The significance value does not indicate whether a result is practically significant. Effect size is another measure from a statistical test. It helps determine the practical significance. IBM® Cognos Analytics uses both the significance value and the effect size to determine whether a result is important enough to display.