categorySourcesPlot {diffeR}

Category Sources plot

Description

If comparison and reference (raster) maps are provided, this function creates the Category Sources plot from the comparison between the comparison map (or map at time t) and the reference map (or map at time t+1). If a square contingency table (matrix) is provided instead of raster maps, then this function creates the Category Sources plot from the comparison between the comparison variable (or variable at time t) and the reference variable (or variable at time t+1).

Usage

categorySourcesPlot(comp = NULL, ref = NULL, ctmatrix = NULL, 
                    analysis = "error", units = NULL, 
                    population = NULL, fontSize = NULL, 
                    breaks = waiver(), labels = waiver(), 
                    limits = NULL)

Arguments

comp

object of class SpatRaster corresponding to a comparison map (or map at time t). See Details below

ref

object of class SpatRaster corresponding to a reference map (or map at time t+1). See Details below

ctmatrix

matrix representing a square contingency table between a comparison variable or variable at time t (rows) and a reference variable or variable at time t+1 (columns). See Details below

analysis

character string indicating type of analysis, either "error" (default) or "change"

units

optional; character string indicating units of ctmatrix

population

optional; an n x 2 matrix provided to correct the sample count to population count in the square contingency table. See Details below

fontSize

text size (in pts)

breaks

One of:

• NULL for no breaks

• waiver() for the default breaks computed by the transformation object

• A numeric vector of positions

• A function that takes the limits as input and returns breaks as output

labels

One of:

• NULL for no labels

• waiver() for the default labels computed by the transformation object

• A character vector giving labels (must be same length as breaks)

• A function that takes the breaks as input and returns labels as output

limits

A numeric vector of length two providing limits of the scale. Use NA to refer to the existing minimum or maximum.

Details

Users may enter as input either a square contingency table (ctmatrix) or a comparison and a reference raster maps (comp and ref, respectively).

The first column of population must contain integer identifiers of each category, corresponding to the categories in the comparison and reference variables. The second column corresponds to the population totals for each category.

Value

a stacked barplot showing for each category the agreement and the omission and comission components of difference between the comparison map/variable (or map/variable at time t) and the reference map/variable (or map/variable at time t+1)

References

Pontius Jr., R.G., Millones, M. 2011. Death to Kappa: birth of quantity disagreement and allocation disagreement for accuracy assessment. International Journal of Remote Sensing 32 (15), 4407-4429.

Examples

comp <- rast(system.file("external/comparison.rst", package = "diffeR"))
ref <- rast(system.file("external/reference.rst", package = "diffeR"))
categorySourcesPlot(comp, ref)

ctmat <- crosstabm(comp, ref)
categorySourcesPlot(ctmatrix = ctmat, units = "Pixels")