search for: c_22

...the diameter increments (per year; DI) in the 3 intervals, in which DI is modelled as a function of mid-interval D and DSQ. The details of the fixed part of the model are not so important here, but four pertinent variables are distance-dependent competition indices: C_spp1fromspp1, C_12, C_21, C_22. The random structure is: random = ~ 1 | PLOT/TREE. More complex random structures aren't required, there's no obvious heterogeneity, and the serial correlations (corSymm) are trivial. I've been trying to fit a spatial correlation structure using the X, Y coordinates of each tree....