2AFC For Dichotomous Observations And Ensemble Forecasts

Routine to calculate the Generalized Discrimination Score (aka Two-Alternatives Forced Choice Score 2AFC) for the situation of dichotomous observations and ensemble forecasts

Usage

afc.de(obsv, fcst, na.rm = FALSE)

Arguments

obsv

vector with dichotomous observations (values in {0,1})

fcst

two-dimensional array with ensemble forecasts; dim(fcst)[1] = length(obsv); dim(fcst)[2] = ensemble size

na.rm

logical; if TRUE pairs where obsv or fcst is NA are removed before scoring. Default FALSE returns NA if any input contains NA.

Value

p.afc

Value of Generalized Discrimination (2AFC) Score

Details

This routine first ranks the ensemble forecasts (see rank.ensembles) and then calculates the 2AFC-score with Eq.2 of Mason and Weigel (2009).

References

S.J. Mason and A.P. Weigel, 2009. A generic verification framework for administrative purposes. Mon. Wea. Rev., 137, 331-349

See also

afc rank.ensembles

Author

Andreas Weigel, Federal Office of Meteorology and Climatology, MeteoSwiss, Zurich, Switzerland

Examples

  data(cnrm.nino34.de)
  obsv = cnrm.nino34.de$obsv
  fcst = cnrm.nino34.de$fcst
  afc.de(obsv,fcst)
#> [1] 0.984