The demographic measurement of migration and its adjustment for under enumeration

William L J Xu-Doeve, .

This paper focuses on the measurement of migration and its adjustment for underenumeration. We first develop an elementary axiomatic-deductive theoretical mathematical framework focusing on the instantaneous rates at which individual demographic events occur in continuous time. Next, we investigate how to establish relationships between abstract theory and empirically-observable events. The mathematical theory is shown to lead to valid measurement methods in an unambiguous and simple manner. Finally, we demonstrate the power of this method by using empirical population census migration data for Bangkok. We show how errors and underenumeration can be corrected in a theoretically-justifiable manner in the general case where one is dealing with deficient data sets. In fact, this approach to measurement is the first truly demographic method of measuring and adjusting migration data in populations for which data are incomplete and defective, such as in statistically less-developed countries or in the case of illegal migration.