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+The incidence decay (ID) estimator assumes an exponential model and finds the parameters by minimizing the sum of the
+squared differences between the observed cases counts and the case counts expected based on the assumed model.
+The method assumes that the serial interval is known. This means that the user needs to input the value of the serial
+interval. The serial interval is the average time between the first infection and the time the first infected individual
+exhibits disease symptoms.