A Lipro household projection model for Flanders: data issues, consistency and household formation scenario setting

Ingrid H. Schockaert, Vrije Universiteit Brussel
Johan Surkyn, Vrije Universiteit Brussel

The purpose of the paper is to discuss some methodological issues of a Household Projection Model for Flanders (2006-2031) based on the Lipro Projection Method. This projection is part of the larger on-going research project Flemosi (Flemish Model for Simulation) that aims at building a simulation model for ex ante evaluation of Flanders socio-economic policies. We will discuss (1) data issues, (2) the problem of consistency and (3) the influence of scenario setting about household formation dynamics on population trends. Using empirical examples, we will clarify the advantages and limitations of the Lipro projection method for the case of Flanders. First, since Lipro-projections have high data demands, data are not readily and only partially available. We will show how we used linked Census and Micro Census data (2001, 2006) and additional information from the National Register to construct the initial population data and rate matrix. Data issues such as incompleteness of the Micro Census data and mortality figures, and their solutions will also be examined. Secondly, we will focus on the impact of consistency constraints to internal transitions on the projection results, comparing the population structure with and without consistency and discussing our results in the light of the recent household projection presented by the Flemish government. Finally, we will introduce scenarios about changes in marriage, divorce, single households and family recomposition and evaluate their influence on the projection results.