Regression Analysis By Example ★ No Sign-up

): This tells you what percentage of the "story" is explained by temperature. If , then 85% of your sales fluctuations are due to heat.

(Error): The "noise"—factors you didn't measure (like a local parade or a broken espresso machine). 2. Checking the "Goodness of Fit"

For a regression to be reliable, your data must pass the "sniff test":

(Slope): For every 1-degree increase in temperature, how many more coffees do you sell?