p-values & Confidence Intervals

Summary

A p-value estimates how surprising your result would be if there were truly no effect; a confidence interval gives a plausible range for the true value — both are ways of quantifying uncertainty.

• 1Learn the common (and wrong) misinterpretations of a p-value, and the correct one.
• 2Practice reading a confidence interval and stating what it does and doesn't mean.
• 3Understand why p < 0.05 is a convention, not a law of nature.