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Modus Operandi: The Methods By Which EPA & ATSDR Keep The Fear Alive

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Formaldehyde: Fact & Fiction

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The Greenhouse Effect Fallacy

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Frank SchnellRSS Feed of this column.

Dr. Frank Schnell, PhD, is a retired toxicologist from the Agency for Toxic Substances and Disease Registry, part of the CDC, in Atlanta, Georgia.... Read More »

When a system is well understood, a well-constructed mathematical model of that system can make realistic predictions based on the data sets fed into it. However, when a system is not well-understood, but one insists on making a mathematical of it, anyway, the holes in the database and the gaps in our knowledge must, necessarily, be filled with assumptions and estimates, instead of established principles and actual data.

The poorer our understanding of the system, the greater the impact of those simplifying assumptions and arbitrary estimates on the modeled results.