The explanatory factors of individual healthcare consumption are studied by means of healthcare expenditures from the 2000–2005 Swiss Household Income and Expenditure Survey (SHIES). In order to tackle the issues of large number of null expenditures and skewed distribution of positive...

In a large sample of Swedish unemployed disabled workers, the workers participate in between zero and ten policy programmes during their unemployment spell. Clustering of programmes to about half of the sample is prominent. <p> The number of programmes is modelled as a standard count data model, as...</p>

We discuss robust estimation of INARCH models for count time series, where each observation conditionally on its past follows a negative binomial distribution with a constant scale parameter, and the conditional mean depends linearly on previous observations. We develop several robust...

Applications of zero-inflated count data models have proliferated in empirical economic research. There is a downside to this development, as zero-inflated Poisson or zero-inflated Negative Binomial Maximum Likelihood estimators are not robust to misspecification. In contrast, simple Poisson...