Modelling methodology and forecast failure

Clements, M. P. ORCID: https://orcid.org/0000-0001-6329-1341 and Hendry, D. F. (2002) Modelling methodology and forecast failure. Econometrics Journal, 5 (2). pp. 319-344. ISSN 1368-423X doi: 10.1111/1368-423X.00086

Abstract/Summary

We analyse by simulation the impact of model-selection strategies (sometimes called pre-testing) on forecast performance in both constant-and non-constant-parameter processes. Restricted, unrestricted and selected models are compared when either of the first two might generate the data. We find little evidence that strategies such as general-to-specific induce significant over-fitting, or thereby cause forecast-failure rejection rates to greatly exceed nominal sizes. Parameter non-constancies put a premium on correct specification, but in general, model-selection effects appear to be relatively small, and progressive research is able to detect the mis-specifications.