textplot_scale1d: Plot a fitted scaling model

Description

Plot the results of a fitted scaling model, from (e.g.) a predicted quanteda.textmodels::textmodel_wordscores model or a fitted quanteda.textmodels::textmodel_wordfish or quanteda.textmodels::textmodel_ca model. Either document or feature parameters may be plotted: an ideal point-style plot (estimated document position plus confidence interval on the x-axis, document labels on the y-axis) with optional renaming and sorting, or as a plot of estimated feature-level parameters (estimated feature positions on the x-axis, and a measure of relative frequency or influence on the y-axis, with feature names replacing plotting points with some being chosen by the user to be highlighted).

Usage

textplot_scale1d(
  x,
  margin = c("documents", "features"),
  doclabels = NULL,
  sort = TRUE,
  groups = NULL,
  highlighted = NULL,
  alpha = 0.7,
  highlighted_color = "black"
)

Value

a ggplot2 object

Arguments

x: the fitted or predicted scaling model object to be plotted
margin: "documents" to plot estimated document scores (the default) or "features" to plot estimated feature scores by a measure of relative frequency
doclabels: a vector of names for document; if left NULL (the default), docnames will be used
sort: if TRUE (the default), order points from low to high score. If a vector, order according to these values from low to high. Only applies when margin = "documents".
groups: grouping variable for sampling, equal in length to the number of documents. This will be evaluated in the docvars data.frame, so that docvars may be referred to by name without quoting. This also changes previous behaviours for groups. See news(Version >= "3.0", package = "quanteda") for details.
highlighted: a vector of feature names to draw attention to in a feature plot; only applies if margin = "features"
alpha: A number between 0 and 1 (default 0.5) representing the level of alpha transparency used to overplot feature names in a feature plot; only applies if margin = "features"
highlighted_color: colour for highlighted terms in highlighted

Author

Kenneth Benoit, Stefan Müller, and Adam Obeng

Examples

Run this code

library("quanteda")
if (require("quanteda.textmodels")) {
dfmat <- dfm(tokens(data_corpus_irishbudget2010))

## wordscores
refscores <- c(rep(NA, 4), 1, -1, rep(NA, 8))
tmod1 <- textmodel_wordscores(dfmat, y = refscores, smooth = 1)
# plot estimated document positions
textplot_scale1d(predict(tmod1, se.fit = TRUE),
                 groups = data_corpus_irishbudget2010$party)
# plot estimated word positions
textplot_scale1d(tmod1, margin = "features",
                 highlighted = c("minister", "have", "our", "budget"))

## wordfish
tmod2 <- quanteda.textmodels::textmodel_wordfish(dfmat, dir = c(6,5))
# plot estimated document positions
textplot_scale1d(tmod2)
textplot_scale1d(tmod2, groups = data_corpus_irishbudget2010$party)
# plot estimated word positions
textplot_scale1d(tmod2, margin = "features",
                 highlighted = c("government", "global", "children",
                                 "bank", "economy", "the", "citizenship",
                                 "productivity", "deficit"))

## correspondence analysis
tmod3 <- textmodel_ca(dfmat)
# plot estimated document positions
textplot_scale1d(tmod3, margin = "documents",
                 groups = docvars(data_corpus_irishbudget2010, "party"))
}