- n is the total number of data points.
- k is the number of joinpoints in the model.
- p is the total number of parameters in the model, including the joinpoint parameters. For our models p=2k+2.
- Qk is the sum of squared errors (SSE) from the model that minimizes SSE with k joinpoints. If a weighted analysis is done (anything but heteroscedastic errors option= constant variance) then Qk represents the minimum weighted SSE.
- Qx,j,k is the (weighted) SSE from the model that minimizes (weighted) SSE with k joinpoints and with the jth joinpoint occurring at x.
- F-1a,b(p) is the pth quantile of the F distribution with a and b degrees of freedom.
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