Models as measuring instruments: measurement of duration dependence of unemployment
Nancy Cartwright views models as blueprints for nomological machines - machines that, if properly shielded, generate law-like behaviour or regularities. Marcel Boumans has argued that we can look for devices inside models, which enable us to measure aspects of these regularities. Therefore, if models do produce regular behaviour (Cartwright), they might perhaps generate numbers about phenomena in the world, provided we can locate a good measuring device in the model (Boumans). How do they do this? Models are often understood to consist of internal principles and bridge principles. Both of these play a role in the measuring process. This paper suggests that we can understand the internal principles to be responsible for generating the regularities displayed by the model - and for many users of the model, this is sufficient use. The bridge principles (following Cartwright - 'the real bridge principles') are a matter of picking the right mathematical representation to make the model work with respect to some real world case at hand. These 'real' bridge principles may enable the model to generate numbers and so serve to make the model into a measuring device. This paper explores this construction of a measuring device of duration dependence of unemployment. Since search theory cannot be made operational for this purpose duration models, which model of the outflow process of unemployment with a Weibull function, are taken as a representation of reservation wage setting in search models. As I show, this Weibull function serves as a bridge principle to make a measure of the elasticity of response between unemployment benefit and duration of unemployment. It enables measurement to take place by modelling behaviour according to some assumptions, which operate as constraints. While this Weibull function serves this purpose, its assumptions are arbitrary rather than connected to theory, and measurements generated with this bridge principle turn out to be highly sensitive to its specification. The Weibull function does enable the model to function as a measuring device, but the lack of ability to make newly invoked unobservable variables operational makes it of dubious worth.
If you experience problems downloading a file, check if you have the proper application to view it first. In case of further problems read the IDEAS help page. Note that these files are not on the IDEAS site. Please be patient as the files may be large.
As the access to this document is restricted, you may want to look for a different version under "Related research" (further below) or search for a different version of it.
Volume (Year): 12 (2005)
Issue (Month): 3 ()
|Contact details of provider:|| Web page: http://www.tandfonline.com/RJEC20|
|Order Information:||Web: http://www.tandfonline.com/pricing/journal/RJEC20|
References listed on IDEAS
Please report citation or reference errors to , or , if you are the registered author of the cited work, log in to your RePEc Author Service profile, click on "citations" and make appropriate adjustments.:
- Albrecht, James W & Axell, Bo, 1983.
"An Equilibrium Model of Search Unemployment,"
Working Paper Series
99, Research Institute of Industrial Economics.
- Lancaster, Tony, 1979. "Econometric Methods for the Duration of Unemployment," Econometrica, Econometric Society, vol. 47(4), pages 939-56, July.
- Lars Peter Hansen & James J. Heckman, 1996. "The Empirical Foundations of Calibration," Journal of Economic Perspectives, American Economic Association, vol. 10(1), pages 87-104, Winter.
- Stephen Machin & Alan Manning, 1998.
"The causes and consequences of long-term unemployment in Europe,"
LSE Research Online Documents on Economics
20255, London School of Economics and Political Science, LSE Library.
- Machin, Stephen & Manning, Alan, 1999. "The causes and consequences of longterm unemployment in Europe," Handbook of Labor Economics, in: O. Ashenfelter & D. Card (ed.), Handbook of Labor Economics, edition 1, volume 3, chapter 47, pages 3085-3139 Elsevier.
- Stephen Machin & Alan Manning, 1998. "The Causes and Consequences of Long-Term Unemployment in Europe," CEP Discussion Papers dp0400, Centre for Economic Performance, LSE.
- Layard, Richard & Nickell, Stephen & Jackman, Richard, 1991.
"Unemployment: Macroeconomic Performance and the Labour Market,"
Oxford University Press, number 9780198284345, December.
- Layard, Richard & Nickell, Stephen & Jackman, Richard, 2005. "Unemployment: Macroeconomic Performance and the Labour Market," OUP Catalogue, Oxford University Press, number 9780199279173, December.
- Narendranathan, W & Nickell, S & Stern, J, 1985. "Unemployment Benefits Revisited," Economic Journal, Royal Economic Society, vol. 95(378), pages 307-29, June.
- Flinn, Christopher J & Heckman, James J, 1983.
"Are Unemployment and Out of the Labor Force Behaviorally Distinct Labor Force States?,"
Journal of Labor Economics,
University of Chicago Press, vol. 1(1), pages 28-42, January.
- Christopher J. Flinn & James J. Heckman, 1982. "Are Unemployment and Out of the Labor Force Behaviorally Distinct Labor Force States?," NBER Working Papers 0979, National Bureau of Economic Research, Inc.
- Spanos,Aris, 1986. "Statistical Foundations of Econometric Modelling," Cambridge Books, Cambridge University Press, number 9780521269124, Junio.
- Marcel Boumans, 1999. "Representation and stability in testing and measuring rational expectations," Journal of Economic Methodology, Taylor & Francis Journals, vol. 6(3), pages 381-402.
When requesting a correction, please mention this item's handle: RePEc:taf:jecmet:v:12:y:2005:i:3:p:407-431. 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: (Michael McNulty)
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.
If references are entirely missing, you can add them using this form.
If the full references list an item that is present in RePEc, but the system did not link to it, you can help with 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 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.