On Interaction Effects: The Case of Heckit and Two-Part Models
AbstractInteraction effects capture the impact of one explanatory variable x1 on the marginal effect of another explanatory variable x2. To explore interaction effects, socalled interaction terms x1x2 are typically included in estimation specifications. While in linear models the effect of a marginal change in the interaction term is equal to the interaction effect, this equality generally does not hold in non-linear specifi cations (AI, NORTON, 2003). This paper provides for a general derivation of interaction effects in both linear and non-linear models and calculates the formulae of the interaction effects resulting from HECKMAN’s sample selection model as well as the Two-Part Model, two regression models commonly applied to data with a large fraction of either missing or zero values in the dependent variable, respectively. Drawing on a survey of automobile use from Germany, we argue that while it is important to test for the significance of interaction effects, their size conveys limited substantive content. More meaningful, and also more easy to grasp, are the conditional marginal effects pertaining to two variables that are assumed to interact.
Download InfoIf 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.
Bibliographic InfoPaper provided by Rheinisch-Westfälisches Institut für Wirtschaftsforschung, Ruhr-Universität Bochum, Universität Dortmund, Universität Duisburg-Essen in its series Ruhr Economic Papers with number 0309.
Length: 24 pages
Date of creation: Jan 2012
Date of revision:
Other versions of this item:
- Manuel Frondel & Colin Vance, 2013. "On Interaction Effects: The Case of Heckit and Two-Part Models," Journal of Economics and Statistics (Jahrbuecher fuer Nationaloekonomie und Statistik), Justus-Liebig University Giessen, Department of Statistics and Economics, vol. 233(1), pages 22-38, January.
- C34 - Mathematical and Quantitative Methods - - Multiple or Simultaneous Equation Models; Multiple Variables - - - Truncated and Censored Models; Switching Regression Models
This paper has been announced in the following NEP Reports:
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.:
- Greene, William, 2010.
"Testing hypotheses about interaction terms in nonlinear models,"
Elsevier, vol. 107(2), pages 291-296, May.
- William H. Greene, 2009. "Testing Hypotheses About Interaction Terms in Nonlinear Models," Working Papers 09-08, New York University, Leonard N. Stern School of Business, Department of Economics.
- Manuel Frondel & Colin Vance, 2009.
"Do High Oil Prices Matter? Evidence on the Mobility Behavior of German Households,"
Environmental & Resource Economics,
European Association of Environmental and Resource Economists, vol. 43(1), pages 81-94, May.
- Manuel Frondel & Colin Vance, 2008. "Do High Oil Prices Matter? – Evidence on the Mobility Behavior of German Households," Ruhr Economic Papers 0072, Rheinisch-Westfälisches Institut für Wirtschaftsforschung, Ruhr-Universität Bochum, Universität Dortmund, Universität Duisburg-Essen.
- Frondel, Manuel & Vance, Colin, 2010. "Driving for fun? Comparing the effect of fuel prices on weekday and weekend fuel consumption," Energy Economics, Elsevier, vol. 32(1), pages 102-109, January.
- Duan, Naihua, et al, 1984. "Choosing between the Sample-Selection Model and the Multi-part Model," Journal of Business & Economic Statistics, American Statistical Association, vol. 2(3), pages 283-89, July.
- Ai, Chunrong & Norton, Edward C., 2003. "Interaction terms in logit and probit models," Economics Letters, Elsevier, vol. 80(1), pages 123-129, July.
- White, Michelle J, 1986. "Sex Differences in Urban Commuting Patterns," American Economic Review, American Economic Association, vol. 76(2), pages 368-72, May.
- Manuel Frondel & Jorg Peters & Colin Vance, 2008.
"Identifying the Rebound: Evidence from a German Household Panel,"
The Energy Journal,
International Association for Energy Economics, vol. 0(Number 4), pages 145-164.
- Manuel Frondel & Jörg Peters & Colin Vance, 2007. "Identifying the Rebound - Evidence from a German Household Panel," Ruhr Economic Papers 0032, Rheinisch-Westfälisches Institut für Wirtschaftsforschung, Ruhr-Universität Bochum, Universität Dortmund, Universität Duisburg-Essen.
- Colin Vance, 2009. "Marginal effects and significance testing with Heckman's sample selection model: a methodological note," Applied Economics Letters, Taylor & Francis Journals, vol. 16(14), pages 1415-1419.
- Colin Vance, 2006. "Marginal Effects and Significance Testing with Heckman’s Sample Selection Model: A Methodological Note," RWI Discussion Papers 0039, Rheinisch-Westfälisches Institut für Wirtschaftsforschung.
- Edward C. Norton & Hua Wang & Chunrong Ai, 2004. "Computing interaction effects and standard errors in logit and probit models," Stata Journal, StataCorp LP, vol. 4(2), pages 154-167, June.
- Birte Pohl & Peter Mulder, 2013.
"Explaining the Diffusion of Renewable Energy Technology in Developing Countries,"
GIGA Working Paper Series
217, GIGA German Institute of Global and Area Studies.
- Pfeiffer, Birte & Mulder, Peter, 2013. "Explaining the diffusion of renewable energy technology in developing countries," Energy Economics, Elsevier, vol. 40(C), pages 285-296.
For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: (Sabine Weiler).
If references are entirely missing, you can add them using this form.