Thursday, September 13, 2007

"A simple mathematical model"

We are grateful for the over view of a mathematical modeler, with an MSc degree in the subject, self employed and freelance in his profession.
He has looked at the basis of the ISG data for us, and comments thus:

"One of the more telling sentences is the penultimate one of section 7.19: "

“The ISG chose to use a relatively simple model rather than a more complicated and potentially more realistic model because the objectives were to reach rather broad conclusions, and because the more realistic models require the specification of many essential unknown features”.

"In mathematical modelling terms, this basically means:"

a) It is a simple model – therefore not even close to modeling a ‘realistic’ scenario. Waste of time basically.

b) The objective was to reach a broad conclusion – ie nothing of substance again.

c) There were many essential unknown features – again the more realistic model that might be of some use can not be used as they don’t have the information.

Our modeler continues:

How can this model, using such basic assumptions and missing key information (because of unknown but essential features) be relied upon for real world decisions that affect people and livelihoods?! It is fine for an academic discussion but that is where it should be kept.

So, it would appear that by opting for a simplified, broad brush model into which to put generalised assumptions, the ISG has turned an embryonic mathematical 'science' into an art form which can be tweaked to achieve their intended answer We would add, that to see the eminent professor actually appear proud of his acceptance of such a political bridle in which to 'work' was quite extraordinary. Illuminating, but extraordinary.

But we digress: in modeling terms, our independent expert describes such input as ;

"simple squared equals stupid". Referring to the fact that the ISG have used a simple model to which they have applied simple assumptions.

We referred to such blind faith in the machinations of skewed input into computers in our post here and also drew our reader's attention to one such extremely broad 'hypothesis', on the relative importance offered to the sacred machine of 2 parts cattle v. 1 part badger, which extruded 50 per cent cattle to cattle transmission - and the inevitable cattle carnage. This input data could have been much more accurate, if information from the Tb 99 tomes had been used. Lord knows we spent long enough filled the goddamn things in.

We note that the ISG have recorded manure spreading as a factor encountered on the vast majority of breakdown farms. Yes. Cows do have that unfortunate habit, and the resultant organic manure is spread. And?