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Furthermore…. References. Katz, R.W. and A.H. Murphy (eds), 1997: Economic Value of Weather and Climate Forecasts. Cambridge University Press, Cambridge.
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Furthermore… • References Katz, R.W. and A.H. Murphy (eds), 1997: Economic Value of Weather and Climate Forecasts. Cambridge University Press, Cambridge. Jolliffe, I.T., and D.B. Stephenson, 2003: Forecast Verification. A Practitioner's Guide in Atmospheric Science. Wiley and Sons Ltd, 240 pp. Click here to see the Table of Contents. von Storch, H. and F.W. Zwiers, 1999: Statistical Analysis in Climate Research. Cambridge University Press, Cambridge. Wilks, D.S., 2006: Statistical Methods in the Atmospheric Sciences. An Introduction. Academic Press, San Diego, 467 pp.
Forecasts 1-4 have POD=0; FAR=1; CSI=0 Fifth forecast has POD>0, FAR<1, CSI>1 O F O F F O F O O F Challenges in Spatial Forecasts
Verifying Extreme Forecasts • What are extremes? • Events large in magnitude • Events rare in occurrence • Traditional skill scores become unstable as the probability of the event becomes increasingly small. • Extreme value statistics. Different distributions are more appropriate for use with extreme events.
Confidence Intervals • Skill scores are statistics and as such it is reasonable to ask for confidence intervals. • Some techniques for estimating confidence intervals • Parametric assumptions and inference • Bootstrapping (re-sampling original data) • Use of holdout data in creating model • Difficulties include • Dependent observations • Huge numbers of observation – everything is significant • Small number of data
