| DoctorVisits {AER} | R Documentation |
Cross-section data originating from the 1977–1978 Australian Health Survey.
data("DoctorVisits")
A data frame containing 5,190 observations on 12 variables.
Journal of Applied Econometrics Data Archive.
http://www.econ.queensu.ca/jae/1997-v12.3/mullahy/
Cameron, A.C. and Trivedi, P.K. (1986). Econometric Models Based on Count Data: Comparisons and Applications of Some Estimators and Tests. Journal of Applied Econometrics, 1, 29–53.
Cameron, A.C. and Trivedi, P.K. (1998). Regression Analysis of Count Data. Cambridge: Cambridge University Press.
Mullahy, J. (1997). Heterogeneity, Excess Zeros, and the Structure of Count Data Models. Journal of Applied Econometrics, 12, 337–350.
data("DoctorVisits")
library("MASS")
## Cameron and Trivedi (1986), Table III, col. (1)
dv_lm <- lm(visits ~ . + I(age^2), data = DoctorVisits)
summary(dv_lm)
## Cameron and Trivedi (1998), Table 3.3
dv_pois <- glm(visits ~ . + I(age^2), data = DoctorVisits, family = poisson)
summary(dv_pois) ## MLH standard errors
coeftest(dv_pois, vcov = vcovOPG) ## MLOP standard errors
logLik(dv_pois)
## standard errors denoted RS ("unspecified omega robust sandwich estimate")
coeftest(dv_pois, vcov = sandwich)
## Cameron and Trivedi (1986), Table III, col. (4)
dv_nb <- glm.nb(visits ~ . + I(age^2), data = DoctorVisits)
summary(dv_nb)
logLik(dv_nb)