What is a p-value? In AP Statistics, it is the probability, assuming the null hypothesis is true, of getting a test statistic as extreme as the one observed or more extreme, in the direction of the alternative hypothesis.
Sources, chapters and credits:
A blind cookie taste test shows it: 60 of 100 students pick the name brand, a computer plays 100 guessing students a thousand times, and we count how often guessing does at least as well.
Sources
College Board, AP Statistics Course and Exam Description. College Board, effective fall 2026, 2026.
Cited for: topic 3.6, p-values: the definition of a p-value, the null distribution, simulated p-values, and what a small p-value shows
An original visual explanation. Animation made with sci_anim:
Media
Airman 1st Class Tryphena Mayhugh / Wikimedia Commons. Source: “KMC kids gear up for Christmas at Elf Boot Camp 151214-F-ZC075-069”, Wikimedia Commons file page License: Public domain.
source