The function cv.trans.psa takes a covariate data frame and replaces
each categorical covariate of n >=3 levels with n new binary
covariate columns, one for each level. Transforms covariate dataframe for
use with the function cv.bal.psa.
cv.trans.psa(covariates, fcol = NULL)A dataframe of covariates, presumably some factors.
An optional vector containing the factor columns in the covariate dataframe. In NULL (default) routine to identfy factors internally.
Returns a dataframe covariates.transformed containing new
columns for each level of more than binary factors. The rest of the
covariate dataframe stays unchanged.
cv.bal.psa, loess.psa,
cstrata.psa, cv.trans.psa
#Note reordering of columns, binary factor and numeric column are unchanged.
f2 <- factor(sample(c(0, 1), 20, replace = TRUE))
f4 <- factor(sample(c("a", "b", "c", "d"), 20, replace = TRUE))
cv <- rnorm(20)
X <- data.frame(f2, f4, cv)
cv.trans.psa(X)
#> $covariates.transformed
#> cv f2_1 f4_a f4_b f4_c f4_d
#> 1 -0.09898883 1 0 0 1 0
#> 2 -0.21605786 1 0 0 1 0
#> 3 0.50664978 1 0 0 1 0
#> 4 0.99449724 1 0 1 0 0
#> 5 0.78302360 1 0 1 0 0
#> 6 1.25934822 1 0 1 0 0
#> 7 0.46098323 1 1 0 0 0
#> 8 -0.80519739 1 0 0 0 1
#> 9 -1.17996740 1 0 1 0 0
#> 10 -0.46861563 0 1 0 0 0
#> 11 1.09600832 1 0 1 0 0
#> 12 0.95827225 0 1 0 0 0
#> 13 -1.14536448 0 0 0 1 0
#> 14 -0.43310893 1 1 0 0 0
#> 15 0.37497048 1 0 0 0 1
#> 16 0.43615008 1 0 1 0 0
#> 17 0.03186639 1 0 0 0 1
#> 18 -1.35088553 0 0 1 0 0
#> 19 -0.67293004 1 0 1 0 0
#> 20 1.15554863 1 0 0 1 0
#>
#
f2 <- factor(sample(c('c', 'C'), 20, replace = TRUE))
f4 <- factor(sample(c("b", "A", "d", "CC"), 20, replace = TRUE))
cv <- rnorm(20)
X <- data.frame(f2, f4, cv)
cv.trans.psa(X)
#> $covariates.transformed
#> cv f2_c f4_A f4_CC f4_b f4_d
#> 1 0.98286969 1 0 0 0 1
#> 2 -1.41432600 0 1 0 0 0
#> 3 1.35000255 1 0 1 0 0
#> 4 -0.45618467 1 0 1 0 0
#> 5 0.77035231 0 0 0 0 1
#> 6 0.22670736 1 1 0 0 0
#> 7 0.53155119 0 0 0 0 1
#> 8 -1.91123935 1 0 0 1 0
#> 9 -0.27473237 1 0 0 0 1
#> 10 0.30921722 0 0 0 0 1
#> 11 1.74375552 0 0 1 0 0
#> 12 2.24954477 1 0 0 1 0
#> 13 0.29422414 1 1 0 0 0
#> 14 -0.75045766 1 0 0 1 0
#> 15 -0.52028475 1 0 0 0 1
#> 16 1.04817126 1 1 0 0 0
#> 17 -0.06630709 0 0 0 0 1
#> 18 -0.20028914 1 0 1 0 0
#> 19 1.41084729 1 0 0 0 1
#> 20 -0.53180900 0 0 1 0 0
#>