Calculates difference in return values (also known as return levels) for two sets of covariates given return period(s) of interest, using model fit from extRemes::fevd. Standard error is obtained via the delta method. The return value is the value for which the expected number of blocks until an event that exceeds that value is equal to the return period. Differences and standard errors are returned for as many contrasts between covariate sets as provided.
calc_returnValueDiff_fevd(
fit,
returnPeriod,
covariates1,
covariates2,
getSE = TRUE
)fitted object from extRemes fevd
value(s) for which return value difference is desired
matrix of covariate values, each row a set of covariates for which the return value difference relative to the corresponding row of covariates2 is desired
matrix of covariate values, each row a set of covariates
logical indicating whether standard error is desired, in addition to the point estimate
This is designed to calculate differences in return values and associated standard errors for different covariate values based on the same model fit. It is not designed for differences based on separate model fits, although it may be possible handle this case by fit two models in a single model specification using dummy variables.