Ecologic studies of this sort have well-known limitations: above all, they make use of aggregate information on the exposure groups and rates of disease rather than information on individuals.

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Aziz, who helped write AlgoRisk 2.3, says the limitations of risk-management software are known.

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At least two of the allies -- Britain and France -- have already made known their objection to inclusion of their air forces under such limitations.

CENTERFORSECURITYPOLICY: Center For Security Policy

This is for example the case of herbal medicine which power is generally underestimated and insufficiently known, or of practices that are exclusively turned to without consideration of their limitations.

UNESCO: Social and Human Sciences