Abstract
R-squared measures of goodness of fit for count data are rarely, if ever, reported in empirical studies or by statistical packages. We propose several R-squared measures based on various definitions of residuals for the basic Poisson regression model and for more general models such as negative binomial that accommodate overdispersed data The preferred R-squared measure is based on the deviance residual. An application to data on health-care-service utilization measured in counts illustrates the performance and usefulness of the various R-squared measures.
Original language | English |
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Pages (from-to) | 209-220 |
Number of pages | 12 |
Journal | Journal of business & economic statistics |
Volume | 14 |
Issue number | 2 |
Publication status | Published - Apr 1996 |
Keywords
- deviance
- deviance residual
- goodness of fit
- negative binomial regression
- Pearson residual
- Poisson regression
- DEVIANCE
- DIAGNOSTICS
- RESIDUALS
- GOODNESS
- FIT