Forum Discussion
R-Squared for Nonlinear Trendlines in Graphs
The r-squared calculation in Excel for nonlinear trendlines previously displayed the quantity developed using the linear regression model of the transformed data. Can anyone point me to the updated equation used to define r-squared in a nonlinear trendline? Below is a example of an exponential trend where the r-squared displayed on the log-linear graph matches the calculated value in cell L7, however, is not consistent with the r-squared in the linear-linear trend despite equivalence of the regression coefficients.
jmt188.... Note that I just made some significant edits to my previous response in order to improve(?) the explanation. If you had trouble following the explanation previously, you might want to reread the edited response.
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- I can probably help you. But I am too lazy to retype your data and reverse-engineer your formulas.
Please attach an Excel file (not an image) that demonstrates the problem.JoeUser2004 Please see the attached file. The y-values include random noise in an effort to ensure r-squared values less than unity. That said, all equations should update each time the worksheet is modified. Thanks for the help.
jmt188.... Note that I just made some significant edits to my previous response in order to improve(?) the explanation. If you had trouble following the explanation previously, you might want to reread the edited response.
