Effect of uncertainties in rate coefficients on densities of E region species

A direct statistical method has been applied to determine the effect of uncertainties in rate coefficients on computed densities of E region species. Uncertainties in rate coefficients are described in terms of Gaussian error law distributions with a common fractional standard deviation. Mean densities are found to be relatively insensitive to rate coefficient uncertainties; fractional standard deviations of density distributions are, in general, less than twice those associated with rate coefficient distributions, provided the fractional standard deviations of the rate coefficient distributions are not greater than 0.45.