Create an array of resampled dfms.

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

Arguments

x

a dfm 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 (with 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.

Author

Kenneth Benoit

Examples

set.seed(10)
txt <- c(textone = "This is a sentence.  Another sentence.  Yet another.",
         texttwo = "Premiere phrase.  Deuxieme phrase.")
dfmat <- corpus_reshape(corpus(txt), to = "sentences") |>
    tokens() |>
    dfm()
bootstrap_dfm(dfmat, n = 3)
#> 
#> $dfm_0
#> Document-feature matrix of: 2 documents, 10 features (45.00% sparse) and 0 docvars.
#>          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 (50.00% sparse) and 0 docvars.
#>          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        0      2        2
#> 
#> $dfm_2
#> Document-feature matrix of: 2 documents, 10 features (65.00% sparse) and 0 docvars.
#>          features
#> docs      this is a sentence . another yet premiere phrase deuxieme
#>   textone    0  0 0        1 3       3   2        0      0        0
#>   texttwo    0  0 0        0 2       0   0        2      2        0
#> 
#> $dfm_3
#> Document-feature matrix of: 2 documents, 10 features (60.00% sparse) and 0 docvars.
#>          features
#> docs      this is a sentence . another yet premiere phrase deuxieme
#>   textone    0  0 0        1 3       3   2        0      0        0
#>   texttwo    0  0 0        0 2       0   0        1      2        1
#> 
#> attr(,"class")
#> [1] "dfm_bootstrap"