What does the "p" in p-value represent?

The "p" in p-value stands for "probability." In statistical hypothesis testing, a p-value is used to determine the strength of the evidence against the null hypothesis. Specifically, it quantifies the probability of obtaining results at least as extreme as the observed results, assuming that the null hypothesis is true. When researchers conduct tests, they want to assess whether the observed data is consistent with the null hypothesis. A low p-value indicates that such an outcome is unlikely under the assumption of the null hypothesis, which often leads to the rejection of the null hypothesis in favor of an alternative hypothesis.

The other options, such as proportion, percentage, and predictability, do not accurately describe the concept conveyed by the p-value in statistical contexts. While a p-value can be expressed as a proportion or as a percentage, its fundamental meaning aligns with the concept of probability, making it crucial for determining the statistical significance of results in hypothesis testing.