Hypothesis Tests and Simulation Envelopes 399
Then simula tion envelop es based on this fitted model can be compu te d simply by
> EH <- envelope(fit, Lest, nsim=39, global=TRUE)
10.8.1.3 Envelopes based on any simulation procedure
Envelopes ca n also be computed using any user-specified proc edure to generate the simulated real-
isations. This allows us to perform rando misation tests, for example.
The simulation procedure should be enc oded as an R expression which, when evaluated, yields
a point pattern. An expression in the R languag e represents a command that has not yet been
executed. It is created by typing expression(.....) whe re the dots represent any command in
R. The expression can then be executed or ‘evaluated’ using eval. Typically