Logarithmic Regression


The logarithmic regression option finds the equation of the form y = a + b ln x that best fits a set of data. First, enter the data.

The values of x must, of course, be greater than zero.



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 logarithmic.



Therefore, the best-fit logarithmic equation for this data is approximately y = - 5.45 + 21.5 ln x.

The correlation coefficient, r, is about 0.995 and the coefficient of determination, r2, is about 0.991. which indicates a very good fit.


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.