Note: if you cannot remember how to interpret least squares regression lines, revise notes for 3.3 Using the Formula for a Fitted Line.
Guideline to Analyse Least Squares Linear Regression Relationships for Transformed Data
- Analysing a least squares linear fit for transformed data is similar to the process for non-transformed data, however you must keep in mind the association is not between the explanatory variable and response variable, it is between the transformed variable and the non-transformed variable (which will be either the explanatory or response variable).
- When interpreting the meaning of the coefficient of determination, it gives an indication of what percentage of variation in the transformed variable is explained by variation of the non-transformed variable, or visa-versa (e.g. for an explanatory variable squared transformation, the coefficient indicates what percentage of variation in y can be explained by variation in x^2).