Create an array of resampled dfms.

bootstrap_dfm(x, n = 10, ..., verbose = quanteda_options("verbose"))

Arguments

x

a character or corpus object

n

number of resamples

...

additional arguments passed to dfm

verbose

if TRUE print status messages

Value

A named list of dfm objects, where the first, dfm_0, is the dfm from the original texts, and subsequent elements are the sentence-resampled dfms.

Details

Function produces multiple, resampled dfm objects, based on resampling sentences (wth replacement) from each document, recombining these into new "documents" and computing a dfm for each. Resampling of sentences is done strictly within document, so that every resampled document will contain at least some of its original tokens.

Examples

# bootstrapping from the original text txt <- c(textone = "This is a sentence. Another sentence. Yet another.", texttwo = "Premiere phrase. Deuxieme phrase.") bootstrap_dfm(txt, n = 3)
#> $dfm_0 #> Document-feature matrix of: 2 documents, 10 features (45% sparse). #> 2 x 10 sparse Matrix of class "dfmSparse" #> features #> docs this is a sentence . another yet premiere phrase deuxieme #> textone 1 1 1 2 3 2 1 0 0 0 #> texttwo 0 0 0 0 2 0 0 1 2 1 #> #> $dfm_1 #> Document-feature matrix of: 2 documents, 10 features (50% sparse). #> 2 x 10 sparse Matrix of class "dfmSparse" #> features #> docs this is a sentence . another yet premiere phrase deuxieme #> textone 1 1 1 2 3 2 1 0 0 0 #> texttwo 0 0 0 0 2 0 0 2 2 0 #> #> $dfm_2 #> Document-feature matrix of: 2 documents, 10 features (55% sparse). #> 2 x 10 sparse Matrix of class "dfmSparse" #> features #> docs this is a sentence . another yet premiere phrase deuxieme #> textone 1 1 1 3 3 2 0 0 0 0 #> texttwo 0 0 0 0 2 0 0 0 2 2 #> #> $dfm_3 #> Document-feature matrix of: 2 documents, 10 features (50% sparse). #> 2 x 10 sparse Matrix of class "dfmSparse" #> features #> docs this is a sentence . another yet premiere phrase deuxieme #> textone 2 2 2 2 3 1 1 0 0 0 #> texttwo 0 0 0 0 2 0 0 2 2 0 #> #> attr(,"class") #> [1] "dfm_bootstrap"