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pbreheny / visreg

Visualization of regression functions
http://pbreheny.github.io/visreg/
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What does the axis label f(x, y) mean? #10

Closed pbreheny closed 8 years ago

pbreheny commented 8 years ago

Joaquín Aldabe (Universidad de la República) writes:

The output of the model indicates that I have a a three way interaction among these three variables and I'm trying to understand it. I did a couple of plots and wanted to check with you their interpretation. What I see is that the Z axis is not BBSA but f(log.AMGP, Grass_height) in the case of these variables. How should I interpret this, as I would expect BBSA as the response variable?

pbreheny commented 8 years ago

The default in visreg is to label the response axis with f(other variables) if the link is nonlinear (or it cannot determine whether the link is nonlinear). For example, if you had a log link in your glmm, then the z-axis should be labeled log(BBSA). However, visreg is not smart enough to automatically determine what the proper axis label should be in nonlinear cases, so it just uses f(other variables) as a generic label; you'd have to change your own label to whatever is appropriate for your model using zlab='My label'.