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"... I have not seen one model tested retrospectively and critically against the reality in the field. .......The truth is in the field, not in the computer."

Comment taken from the ProMed website for July 2002. The page details FOOT & MOUTH DISEASE - UK: FORMAL INQUIRIES (02) and, following the Royal Society report, quotes in full the Times article "Foot-and-mouth report: "vaccinate in future"

[The summary of the report can be seen at

The Inquiry's full report can be seen at <> and includes also the oral and written evidence. -Mod.AS]

The moderator MHJ comments: [Reading the Summary & Main Recommendations there is very little one can disagree with, and much to agree with. It is a sound document. But there are two points that have been ignored and they are important: I have not seen one model tested retrospectively and critically against the reality in the field.
Predictions are not the same as reality. All that was done was to see if the curves matched generally. This testing should have been done last year during the epidemic and certainly against the modelers' demand for 3kms culling. There was sufficient field experience and GIS topographic and detailed agricultural data to put it in doubt and certainly to hard test. I have a phrase I use on my students and those over-enamored of their computers and models, "Why should I believe you when you have a computer pallor and no mud on your shoes?" The truth is in the field, not in the computer. When models are checked and rechecked against reality they can be fine-tuned and may eventually become useful.

Remember that they all start as merely the mathematical expression of the model builder's presumptions and assumptions.

[2] During any emergency, big or small, appropriate data must be collected and kept securely to allow a critical retrospective post-mortem. This may need a special forensic team with funding to independently assess what had happened and why, using ministry samples and data collected during the epidemic and even additional data collected subsequently. When all the dust has settled and honors awarded, one must be able to sit down and work out, without blame, what went right, what could have been done better, and play "what-if" if one is to ever get it right. Plus the next time will be different. If there are good databases, they can be used to model the future and ask new questions. Also these data should be readily shared.

Based on my experience, I fear both are hobby horses; I have built my share of mathematical models. Some fall in love with their models but you should never marry them. And the truth is in the field. - Mod.MHJ]