esc {pairwise}

Expected Score Curves Plots

Description

plotting function for plotting expected score curves.

Usage

esc(pers_obj, itemnumber = 1, integ = 6, ra = 4, nodes = 100, lwd = 2, ...)

Arguments

pers_obj

an object of class "pers" as a result from function pers.

itemnumber

an integer, defining the number of the item to plot the respective categoy probability for. This is set to an arbitrary default value of itemnumber = 1 to avoid error messages when you forget to choose an item to plot the expected score curves for.

integ

either an integer defining the number of (ability) groups to integrate the empirical theta vector or the character expression "all" to plot the empirical theta distribution at the respective item score using symbols (see example).

ra

an integer, defining the (logit) range for x-axis

nodes

numer of integration nodes

lwd

see plot

...

arguments passed to plot

Details

no details in the moment.

Examples

########
data(bfiN)
result <- pers(pair(bfiN))
esc(pers_obj=result,1,lwd=2) # plot for first item
esc(pers_obj=result,2,lwd=2) # plot for second item
for(i in 1:5){esc(pers_obj=result,i,lwd=2)}
#########
esc(pers_obj=result,2,integ="all",lwd=2) # plot for secod item