P-value Calculator
Calculate p-values for statistical hypothesis testing with our free online calculator. Understand statistical significance and interpret your research results.
Category: Calculator
Frequently Asked Questions
What is a p-value?
A p-value is the probability of obtaining results at least as extreme as those observed, assuming the null hypothesis is true. In simpler terms, it measures how likely your data would occur by random chance alone. Smaller p-values indicate stronger evidence against the null hypothesis.
How do I interpret p-values?
P-values are interpreted in relation to a significance level (alpha), typically 0.05. If the p-value is less than alpha, you reject the null hypothesis, suggesting your results are statistically significant. If the p-value is greater than alpha, you fail to reject the null hypothesis, suggesting insufficient evidence for your alternative hypothesis.
What are common mistakes when using p-values?
Common mistakes include: 1) Thinking a low p-value proves your hypothesis is true (it only suggests evidence against the null), 2) Believing a high p-value proves the null hypothesis, 3) P-hacking by running multiple tests until finding significance, 4) Ignoring effect size and only focusing on statistical significance, and 5) Misinterpreting the p-value as the probability that the null hypothesis is true.