statico.krandtest function

Monte-Carlo test on a Statico analysis (in C).

Performs the series of Monte-Carlo coinertia tests of a Statico analysis (one for each couple of tables).

statico.krandtest(KTX, KTY, nrepet = 999, ...)

Arguments

• KTX: an objet of class ktab containing the environmental data
• KTY: an objet of class ktab containing the species data
• nrepet: the number of permutations
• ...: further arguments passed to or from other methods

Details

This function takes 2 ktabs and does a coinertia analysis with coinertia on each pair of tables. It then uses the randtest function to do a permutation test on each of these coinertia analyses.

Returns

krandtest, a list of randtest objects. See krandtest

References

Thioulouse J. (2011). Simultaneous analysis of a sequence of paired ecological tables: a comparison of several methods. Annals of Applied Statistics, 5 , 2300-2325.

Author(s)

Jean Thioulouse jean.thioulouse@univ-lyon1.fr

WARNING

IMPORTANT : KTX and KTY must have the same k-tables structure, the same number of columns, and the same column weights.

Examples

data(meau)
wit1 <- withinpca(meau$env, meau$design$season, scan = FALSE, scal = "total")
spepca <- dudi.pca(meau$spe, scale = FALSE, scan = FALSE, nf = 2)
wit2 <- wca(spepca, meau$design$season, scan = FALSE, nf = 2)
kta1 <- ktab.within(wit1, colnames = rep(c("S1","S2","S3","S4","S5","S6"), 4))
kta2 <- ktab.within(wit2, colnames = rep(c("S1","S2","S3","S4","S5","S6"), 4))
statico1 <- statico(kta1, kta2, scan = FALSE)
kr1 <- statico.krandtest(kta1, kta2)
plot(kr1)