October 2012
Beginner
420 pages
9h 37m
English
25.1 Tree
| Column | Content |
| C1 | Tree diameter at a certain distance from the ground (in cm) |
| C2 | Tree height (in m) |
| C3 | Volume of useable timber (in dm3) |
The bivariate plots (Graph > Matrix Plot > Each Y versus each X: Simple) clearly show that the best model with only one regressor is the one that explains the volume as a function of the diameter. In the following, this model is studied in detail:
Stat > Regression > Regression
The plots for the residual analysis (in the dialog box Regression, press button Graphs and choose Four in one) look as follows:
The most notable issue is that in the second graph, residuals versus fitted values (Versus ...
Read now
Unlock full access