scoring (version 0.4)

WeatherProbs: Three-category weather forecasts

Description

Probabilistic forecasts from the U.S. National Oceanic and Atmospheric Administration, concerning below/near/above average temperatures and below/near/above median precipitation.

Usage

data("WeatherProbs")

source

Data were obtained from http://www.cpc.ncep.noaa.gov/products/archives/short_range/.

Details

The forecasts are valid for a period of 6 to 10 days from the date that the forecast was made. The forecasts were supplied every weekday during April, 2009, and they specifically predict the average temperature or total precipitation for the entire valid period.

References

See http://www.cpc.ncep.noaa.gov/products/archives/short_range/README.6-10day.txt for more details on the data.

For an application of similar data (different dates, same source), see:

Wilks, D. S. (in press). The calibration simplex: A generalization of the reliability diagram for 3-category probability forecasts. Weather and Forecasting.

Examples

data("WeatherProbs")

## Brier score for temperature forecasts
## (Warning arises because some forecast rows don't sum to 1.)
res <- calcscore(tcat ~ tblw + tnrm + tabv, data=WeatherProbs,
                 bounds=c(0,1))

## Spherical score for temperature forecasts
res2 <- calcscore(tcat ~ tblw + tnrm + tabv, data=WeatherProbs,
                  fam="sph", bounds=c(0,1))

## Average scores by station
avgbrier <- with(WeatherProbs, tapply(res, stn, mean))
avgsph <- with(WeatherProbs, tapply(res2, stn, mean))

## Comparison
plot(res, res2, pch=20, xlab="Brier", ylab="Spherical")