DHARMa (version 0.2.7)

transformQuantiles: Transform quantiles to pdf

Description

The purpose of this function is to transform the DHARMa quantile residuals (which have a uniform distribution) to a particular pdf.

Usage

transformQuantiles(res, quantileFunction = qnorm, outlierValue = 7)

Arguments

res

DHARMa residuals

quantileFunction

the quantile function of the desired distribution

outlierValue

the value that should be assigned to residuals that are 0/1 and thus typically mapped to -Inf / Inf for continous distributions with infinte support

Details

Some of the papers on simulated quantile residuals transforming the residuals (which are natively uniform) back to a normal distribution. I presume this is because of the larger familiarity of most users with normal residuals. Personally, I never considered this desirable, for the reasons explained in https://github.com/florianhartig/DHARMa/issues/39, but with this function, I wanted to give users the option to plot normal residuals if they so wish.

Examples

# NOT RUN {
set.seed(1)
testData = createData(sampleSize = 200, family = poisson())
fittedModel <- glm(observedResponse ~ Environment1, 
                     family = "poisson", data = testData)
res <- simulateResiduals(fittedModel = fittedModel)
plot(res$fittedPredictedResponse, transformQuantiles(res))

# }