Research on Modifications to the Method of Preliminary Estimates of Interprovincial Migration - ARCHIVED

The Population Estimates Program at Statistics Canada is using internal migration estimates derived from administrative sources of data. There are two versions of migration estimates currently available, preliminary (P), based on Child Tax Credit information and final (F), produced using information from income tax reports. For some reference dates they could be significantly different. This paper summarises the research undertaken in Demography Division to modify the current method for preliminary estimates in order to decrease those differences. After a brief analysis of the differences, six methods are tested: 1) regression of out-migration; 2) regression of in- and out-migration separately; 3) regression of net migration; 4) the exponentially weighted moving average; 5) the U.S. Bureau of Census approach; and 6) method of using the first difference regression. It seems that the methods in which final and preliminary migration data are combined to estimate preliminary net migration (Method 3) are the best approach to improve convergence between preliminary and final estimates of internal migration for the Population Estimation Program. This approach allows for "smoothing" of some erratic patterns displayed by the former method while preserving CTB data's ability to capture current shifts in migration patterns.