IDEAS home Printed from
   My bibliography  Save this article

Internal and External Consistency in Multidimensional Population Projection Models


  • N W Keilman

    (Netherlands Interuniversity Demographic Institute (NIDI), PO Box 955, 2270 AZ Voorburg, The Netherlands)


In this paper the impact of consistency requirements upon the formulation of multidimensional population projection models is dealt with. The problem of internal consistency arises when certain output variables of the model have to be consistent with one another, as in models containing marital status (two-sex problem). External consistency problems arise when certain output variables have to satisfy externally specified restrictions. For instance, regional population projections may have to add up to national projections. The paper gives internal and external consistency algorithms, which control both for stock and for flow variables. Two approaches are discussed: a simple proportional adjustment for each relevant demographic component and an approach that minimises deviations in age-specific patterns of the input rates. Both algorithms are illustrated using data from the Netherlands. In the first illustration the internal consistency algorithm is applied to the age, sex, and marital-status-specific model of the official 1980 national population forecasts. In the second, external consistency is considered within the context of the multiregional projection model which was constructed for the regional population forecasts for the Netherlands.

Suggested Citation

  • N W Keilman, 1985. "Internal and External Consistency in Multidimensional Population Projection Models," Environment and Planning A, , vol. 17(11), pages 1473-1498, November.
  • Handle: RePEc:sae:envira:v:17:y:1985:i:11:p:1473-1498

    Download full text from publisher

    File URL:
    Download Restriction: no

    Other versions of this item:


    Citations are extracted by the CitEc Project, subscribe to its RSS feed for this item.

    Cited by:

    1. Karine Briard, 2009. "Un modèle de carrières types dynamiques pondérées pour le régime général d’assurance vieillesse : une application aux conséquences de la réforme de 2003," Économie et Prévision, Programme National Persée, vol. 187(1), pages 47-64.
    2. Dik Leering & Andries Hans De Jong, 2005. "Pearl - The New Regional Forecasting Model Of The Netherlands," ERSA conference papers ersa05p420, European Regional Science Association.
    3. Nijkamp, Peter & Van Wissen, Leo & Rima, Annemarie, 1993. "A household life cycle model for residential relocation behaviour," Socio-Economic Planning Sciences, Elsevier, vol. 27(1), pages 35-53, March.

    More about this item


    Access and download statistics


    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:sae:envira:v:17:y:1985:i:11:p:1473-1498. See general information about how to correct material in RePEc.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: (SAGE Publications). General contact details of provider: .

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    We have no references for this item. You can help adding them by using this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service hosted by the Research Division of the Federal Reserve Bank of St. Louis . RePEc uses bibliographic data supplied by the respective publishers.