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-This is a short description of the IDEA method.
+The Incidence Decay and Exponential Adjustment (ID) estimator is an alternative formulation of the Incidence Decay (ID) model which includes a decay factor to reflect the often observed outbreak decline.
+This addresses the potential underestimation of the $R_0$ estimate when using the ID method.
+The method of least squares is used to estimate $R_0$, and similar to the ID model, the serial interval is assumed to be known and this method is developed assuming the SIR model.
+We note that, since we need to obtain a minimizer of the decay factor to solve the optimization problem, we require that the number of cases in the dataset be at least 2.