Page History
Table of Contents
Relative Operating Characteristics (ROC)
The Relative Operating Characteristics give a measure of the effectiveness of a forecast system to predict an event that actually happens balanced against forecast of an event that fails to occur. ROC is derived from measuring the area beneath the results plotted on a ROC diagram. ROC area values indicate:
...
Fig8.3.3-1: ROC diagram for 850hPa temperature for the verifying period Sep, Oct, Nov derived from SEAS5 runs with data time of early Aug. Points above the lower left/upper right diagonal signify skill. The ROC score or value is the area beneath the red curve.
Reliability diagrams
The Reliability diagrams give a measure of the tendency of the forecast system to over- or under-forecast and event. The diagram plots the frequency of a forecast probability of an event against the frequency that the event occurs. Ideally these should match and is shown by the diagonal line. Where the plot lies:
...
Fig8.3.3-2: reliability diagram for precipitation for the verifying period Sep, Oct, Nov derived from SEAS5 runs with data time of early Aug. Points above the diagonal signify under-forecasting, points below the diagonal signify over-forecasting.
Relative Operating Characteristics skill score charts
The Relative Operating Characteristics (ROC) skill score charts give a measure of how well the seasonal (SEAS5) forecast anomalies have represented the observed anomalies.
...
Black dots signify 95% confidence.
(FUG Associated with Cy49r1)
Overview
Community Forums
Content Tools