Fit Line and Fit Polynomial

Using the Fit Line option, you can add straight line fits to your scatterplot using least squares regression. Using the Fit Polynomial option, you can fit polynomial curves of a certain degree using least squares regression.

Figure 5.8 Example of Fit Line and Fit Polynomial 

Figure 5.8 shows an example that compares a linear fit to the mean line and to a degree 2 polynomial fit.

Note the following information:

• The Fit Line output is equivalent to a polynomial fit of degree 1.

• The Fit Mean output is equivalent to a polynomial fit of degree 0.

For more information about the options in the Linear Fit and Polynomial Fit Degree menus, see Fitting Menus. For statistical details about this fit, see Fit Line.