Spearman Simultaneous Estimation for a Compartmental Model

A compartmental model is presented for tracer experiments with a fixed and known amount of tracer material which is injected initially into a single compartment and accumulates in another compartment. The model could also arise as a description of chemical reactions. The model is represented as a system of linear combinations of exponentials with common exponential parameters. Then a simultaneous estimation procedure, which is a generalization of the Spearman estimation procedure presented by Johnson and Brown [7] for a single equation, is developed for this model under the assumption that the values of the independent variable in the model are equally spaced on a logarithmic scale. Asymptotic properties of the estimation procedure are investigated and an example is given.