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Overview

Welcome to the wiki for the Vector Autoregressive Spatio-Temporal (VAST) model.

I post most materials regarding VAST on the wiki of its main dependency, package SpatialDeltaGLMM, and please see materials here. However, I will add materials to the VAST wiki that apply only to VAST.

How to simulate new data

I am adding a new feature starting with Version 4.4.0 (i.e., Version=VAST_v4_4_0) that allows users to generate a new data set using a parametric bootstrap. To do so, (1) build a model using an existing data set, (2) estimate parameters, and (3) use the simulate feature inherited from TMB

# Build object using standard inputs including the original data set `data`
Obj = Build_TMB_Fn( TmbData=data, ... )
# Optimize
Opt = TMBhelper::Optimize( obj=Obj )
# Simulate new data
Sim = Obj.simulate( complete=TRUE )

You can then fit this new data set easily and compare results with your original fit

# Build new object using simulated data `Sim`
Obj_new = Build_TMB_Fn( TmbData=Sim, ... )
# Re-optimize
Opt_new = TMBhelper::Optimize( obj=Obj_new  )
# Compare results
cbind( summary(Opt$SD,"fixed"), summary(Opt_new$SD,"fixed") )