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Plot Optimal Classification (OC) Coordinates for a Specific Roll Call

Source: R/plot_oc_rollcall.R
plot_oc_rollcall.Rd

This function creates a scatter plot of legislators' ideal points based on the results of an Optimal Classification (OC) analysis for a specific roll call. The coordinates can be optionally rotated using a rotation matrix and plotted with different shapes and colors for different groups.

Usage

plot_oc_rollcall(
  obj,
  data,
  shapeVar = NULL,
  rcnum,
  rotMat = diag(2),
  dropNV = FALSE,
  onlyErrors = FALSE,
  ptSize = 4
)

Arguments

obj

An object of class OCobject containing the results of an Optimal Classification analysis, including legislators' ideal points.

data

A rollcall object containing the voting data corresponding to the OC analysis.

shapeVar

An optional variable used to differentiate groups of legislators by shape and color in the plot. If provided, the points will be shaped and colored according to this variable.

rcnum

An integer specifying the roll call number to be visualized.

rotMat

A 2x2 rotation matrix used to rotate the coordinates. The default is the identity matrix (no rotation).

dropNV

A logical value indicating whether to drop non-voters (NA values) from the plot. Default is FALSE.

onlyErrors

A logical value indicating whether to plot only those observations where classification errors occurred. Default is FALSE.

ptSize

A numeric value specifying the size of the points in the plot. Default is 4.

Value

A ggplot object displaying the legislators' coordinates for the specified roll call, optionally with different shapes and colors for different groups.

Examples

if (FALSE) { # \dontrun{
# Assuming `oc_result` is an OCobject, `rc_data` is a rollcall object,
# and `legislator_data` contains a grouping variable
g <- plot_oc_rollcall(oc_result, data = rc_data, 
shapeVar = legislator_data$group, rcnum = 5, dropNV = TRUE)
print(g)
} # }