Power Regression

The power regression option finds the equation of the form y = axb that best fits a set of data. First, enter the data.

The values of x and y must be greater than zero. (This is because the method for determining the values of a and b in the regression equation is a least-squares fit on the values for ln x and ln y.)

The data shown here are the points {(2,11.4), (3,17),(5,27.3),(7,36.1), (11,47.7), (13,49.9)}.

Press to view the statistics calculation options.

Press for regressions, then to select power.

Therefore, the best-fit power equation for this data is approximately y = 7.01x0.8.

The correlation coefficient, r, is about 0.992 and the coefficient of determination, r2, is about 0.986.

Note: If an error message occurs, make sure the data was entered correctly or press to view the setup.

Use , , and the menu keys to select List1 for 2Var XList, List2 for 2Var YList, and 1 for 2Var Freq.