Abstract
Many experiments in chemical kinetics are initiated by a fast pulse, such as electric discharge, shock wave, flash lamp, or laser. After this pulse one observes the production and subsequent decay of a reactive intermediate. One then postulates a mechanism and adjusts the associated rate constants so as to minimize the difference between the results of the experiment and the prediction of the mechanism. The parameters to be estimated are usually strongly correlated, so that it is not possible to determine them separately. These estimated parameters are of little value unless we can also estimate statistically valid confidence limits for them. The difficulties are discussed which frequently arise in estimating parameters and confidence limits for a kinetic mechanism which is widely used in interpreting laser excitation and fluorescence measurements, that is, firstβorder production and decay. These difficulties, and methods for dealing with them, are illustrated with realistic data. The estimation problem is particularly ill conditioned when the production and loss rates are nearly equal. In some experimental systems this can be avoided, but in others it is inevitable.