plotMCC {conquestr}

R Documentation

plotMCC

Description

Creates a plot of an item characteristic curve (by response category). For a dichotomous item, this will yield a single curve, for polytomous items this will produce a curve for each response category. Note this is not for use with rout files. See the generic function plotRout for plotting rout files.

Usage

plotMCC(item, data, range = c(-6, 6), e_linetype = "bins", bins = 6)

Arguments

item	Item parameters for a single item.
data	Two vectors of data in an n by 2 matrix or data frame, where n are the cases in your analysis. The first vector should be item responses. the second vector should be estimated person abilities.
range	Lower and upper bounds to plot over (defaults to c(-6, 6) OR the minimum and maximum estimated ability, whichever is larger).
e_linetype	A string. Should the empirical lines be based on "bins", or "regression". Defaults to "bins"
bins	If _e\emphlinetype is "bins", how many bins should be used to chunk the empirical lines? defaults to 6. Ignored otherwise.

Value

A ggplot2 object.

Examples

myRout <- ConQuestRout()
myPlot <- plotRout(myRout)
## Not run: 
# if you run the above example you will have an ICC plot in the object `myPlot`.
plot(myPlot)

## End(Not run)

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