The probability for the climatological forecast is always 0.33 and the verifying probability of the three forecast systems is usually greater than this value.
For a climatological forecast, the probabilities [p.sub.clim] forecasted for each tercile are 1/3 = 33.3%.
The inset table shows various measures of forecast quality: i) linear correlation index (Corr), ii) Kendall ranked correlation (Rank), and the mean absolute SS with respect to iii) a climatological forecast (Clim) and iv) a 10-yr persistence forecast (Pers).
At the beginning of round I, the player using predictions from the forecast systems puts 29% of the money on the winning category, whereas the player using the climatological forecast puts 33%.
Probabilistic forecast verification, (top) The probability of the verifying tercile as predicted by each of the forecast systems, the climatological forecast, and the mix climatology-persistence forecast, (middle) Return ratio for each forecast system when playing against the climatological forecast.