Monte-Carlo Test on the sum of the singular values of a procustean rotation (in C).

performs a Monte-Carlo Test on the sum of the singular values of a procustean rotation.

Usage

procuste.randtest(df1, df2, nrepet = 999, ...)

Arguments

df1: a data frame
df2: a data frame
nrepet: the number of permutations
...: further arguments passed to or from other methods

Value

returns a list of class randtest

References

Jackson, D.A. (1995) PROTEST: a PROcustean randomization TEST of community environment concordance. Ecosciences, 2, 297--303.

Author

Jean Thioulouse Jean.Thioulouse@univ-lyon1.fr

Examples

data(doubs)
pca1 <- dudi.pca(doubs$env, scal = TRUE, scann = FALSE)
pca2 <- dudi.pca(doubs$fish, scal = FALSE, scann = FALSE)
protest1 <- procuste.randtest(pca1$tab, pca2$tab, 999)
protest1
#> Monte-Carlo test
#> Call: procuste.randtest(df1 = pca1$tab, df2 = pca2$tab, nrepet = 999)
#> 
#> Observation: 0.6562 
#> 
#> Based on 999 replicates
#> Simulated p-value: 0.001 
#> Alternative hypothesis: greater 
#> 
#>     Std.Obs Expectation    Variance 
#> 6.620187464 0.342806331 0.002240989 
plot(protest1,main="PROTEST")