A new approach to truncated regression for count data

Standard Poisson and negative binomial truncated regression models for count data include the regressors in the mean of the non-truncated distribution. In this paper, a new approach is proposed so that the explanatory variables determine directly the truncated mean. The main advantage is that the re...

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Bibliographic Details
Authors: Martínez-Rodríguez, Ana M., Conde-Sánchez, Antonio, Olmo-Jiménez, María J.
Format: article
Status:Versión aceptada para publicación
Publication Date:2018
Country:España
Institution:Universidad de Jaén
Repository:RUJA. Repositorio Institucional de la Producción Científica de la Universidad de Jaén
OAI Identifier:oai:ruja.ujaen.es:10953/1858
Online Access:https://doi.org/10.1007/s10182-018-00345-x
https://hdl.handle.net/10953/1858
Access Level:Open access
Keyword:Count data
Hurdle model
Negative binomial regression
Poisson regression
Truncated models
Description
Summary:Standard Poisson and negative binomial truncated regression models for count data include the regressors in the mean of the non-truncated distribution. In this paper, a new approach is proposed so that the explanatory variables determine directly the truncated mean. The main advantage is that the regression coefficients in the new models have a straightforward interpretation as the effect of a change in a covariate on the mean of the response variable. A simulation study has been carried out in order to analyze the performance of the proposed truncated regression models versus the standard ones showing that coefficient estimates are now more accurate in the sense that the standard errors are always lower. Also, the simulation study indicates that the estimates obtained with the standard models are biased. An application to real data illustrates the utility of the introduced truncated models in a hurdle model. Although in the example there are slight differences in the results between the two approaches, the proposed one provides a clear interpretation of the coefficient estimates.