Skip Navigation Links www.nws.noaa.gov 
NOAA logo - Click to go to the NOAA home page National Weather Service   NWS logo - Click to go to the NWS home page
Climate Prediction Center
 
 

CPC Search
HOME> Expert Assessments> Hazards Assessment> Hazards Briefing> Hazards Assessment Verification
 
Hazards Assessment Verification for Severe Storms
 
This page updated on 11/29/2008
 
 
The Contingency Table
A
B
C
D
 
Where A=Number of Correct Forecasts,
B=Number of Incorrect Forecasts,
C=Number of Times Event Occured when no Forecast was Made,
D=Number of Times Event did not Occur when no Forecast was Made
 
 
Contingency Table for Latest Forecast (Made on:20081114):
00
3878
 
Cumulative Contingency Table:
18934768
71121281579
 
Hit Rate = (a+d)/(a+b+c+d)
Threat Score = (a)/(a+b+c)
 
Probability of Detection = (a)/(a+c)
False Alarm Rate = (b)/(a+b)
 
Bias = (a+b)/(a+c)
Means
 AllFcst
Hit Rate
0.7910.712
Threat Score
0.0190.096
Prob. of Detection
0.0260.133
False Alarm Rate
0.1400.691
Bias
0.0960.492

NOAA/ National Weather Service
National Centers for Environmental Prediction
Climate Prediction Center
5830 University Research Court
College Park, Maryland 20740
Climate Prediction Center Web Team
Page last modified: August 12, 2003
Disclaimer Privacy Policy