Chapter 14 – Correlation and Simple Regression. Math 22 Introductory Statistics. Numerical Vs. Numerical Variables. Scatterplot - Way to display bivariate data. Scatterplots.
Chapter 14 – Correlation and Simple Regression
A scatterplot is useful for displaying trends in the data and revealing any association that might exist between the two variables of bivariate data. If the two variables are related, we then ask:
If r = 1 or r = -1
If r = 0
Perfect Linear Correlation
No linear correlation. x and y are not linearly related, but they still may be related in another way.
As one variable increases, the other increases.
As one variable decreases, the other decreases.
As one variable increases, the other decreases (and visa-versa).
Variable we wish to predict or describe based on the values of another variable.
Variable that is used to predict the response variable.