Regression and Correlation for Two Metric Variables

Abstract

Questions about relationships between metric variables with well-defined units of measurement, such as food calories and fat content, gas mileage and vehicle weight, are answered using the statistical methods know as regression analysis and correlation analysis. Regression and correlation analyses represent two major and complementary aspects of the analysis of the relationship between metric variables.

Do foods with higher fat content contain more calories than foods with lower fat content? What is the relationship between the weight of a car and the mileage it gets? How do robbery rates relate to larceny rates in the various states? Is there a relationship between cigarette consumption and cancer rates in different countries? How does the percentage of people with low education relate to the percentage of people with low income in different states? Is there a relationship between how tall parents are and how tall their children grow? Has there been any change in malignant melanoma cases in the last decades? How has the world record in the men’s mile race changed since Roger Bannister broke the four-minute barrier in 1954?