Open AccessAnother look at the contingency tables: scores based on Manhattan distances in the phase space
Author(s) -
Stein Joël
Publication year - 2011
Publication title -
meteorological applications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.672
H-Index - 59
eISSN - 1469-8080
pISSN - 1350-4827
DOI - 10.1002/met.199
Subject(s) - contingency table , function (biology) , forecast skill , statistics , representation (politics) , limit (mathematics) , econometrics , phase (matter) , space (punctuation) , computer science , quality (philosophy) , mathematics , meteorology , geography , mathematical analysis , physics , quantum mechanics , evolutionary biology , politics , political science , law , biology , operating system
This alternative presentation of scores is based on the Manhattan distance in the phase space of forecasts. The key factor is represented by the ratio of the weights assigned to misses and false alarms. This ratio is 1 for the Heidke skill score and is equal to the ratio of the number of non‐events to the number of events for the Pierce skill score. A score based on the deterministic limit leads to assign this ratio to either 2 or 0.5 as a function of the base rate. It can also be determined as a function of parameters of a cost‐loss economical model. Applied to the Finley tornadoes and to two quantitative precipitation forecasts, the geographical representation of the phase space is quite invaluable as it points out the good points and the drawbacks of the forecast. The skill scores deduced from these distances help to summarize the quality of a forecast. Copyright © 2010 Royal Meteorological Society