Computer models not always accurate

To the editor:

The Spectrum piece by Mike Nizich (Feb. 1) accurately portrayed the misuse of the Endangered Species Act to frustrate and delay any development efforts that involve the use of natural resources such as timber harvest, mining, petroleum exploration and use, etc. His article refers to the use of computer models to predict impact of the proposed actions in the future. Often the predictions are for future decades and centuries.

I would like to comment that computer models used for these predictions are almost always based on a combination of data and so-called professional estimates that are simply educated guesses. These estimates (guesses) can number in the hundreds for complicated models. It is important for people to understand that an error in any of these estimates will result in a prediction that is wrong. The more estimates, the greater the chance of error unless there are exactly compensating factors.

In my opinion, it would be was to be very cautious when making decisions based on the results of these types of computer models.

John Raynor

Wasilla