WORKING PAPER SERIES
13/9: A ZERO INFLATED REGRESSION MODEL FOR
Sarah Brown, Alan Duncan, Mark Harris,
Jennifer Roberts and Karl Taylor
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© Bankwest Curtin Economics Centre, October 2013
Bankwest Curtin Economics Centre Working Paper Series
Sarah Brown1, Alan Duncan2, Mark Harris2,3, Jennifer Roberts1 & Karl Taylor1
Department of Economics, University of Sheffield, United Kingdom
Bankwest Curtin Economics Centre, Curtin Business School, Australia
School of Economics and Finance, Curtin University, Australia
Brown, S., Duncan, A.S., Harris, M.N, Roberts, J. and Taylor, K. (2013), ‘A Zero Inflated Regression Model for Grouped Data’,
Bankwest Curtin Economics Centre Working Paper 13/9, Perth: Curtin University.
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A ZERO INFLATED REGRESSION MODEL
FOR GROUPED DATA
Sarah Brown1, Alan Duncan2, Mark Harris2,3, Jennifer Roberts1 and Karl Taylor1
of Economics, University of Sheffield, United Kingdom
Curtin Economics Centre (BCEC), Curtin Business School, Australia
of Economics and Finance, Curtin University, Australia
We introduce the (panel) zero-inflated interval regression (ZIIR) model, which is ideally suited when data are in the form of groups, which is commonly the case in survey data, and there is an ‘excess’ of zero observations. We apply our new modelling framework to the analysis of visits to general practitioners (GPs) using individual-level panel data from the British Household Panel Survey
(BHPS). The ZIIR model simultaneously estimates the