537
Table 11.9
Estimated panel data models for doctor visits (standard errors in parentheses)
Variable Poisson
Negative binomial
Pooled(robust s.e.)
Fixed effects Random
effects
Pooled NB2 Fixed effects
Random effects
FE-NB1
FE-NB2
HHG-gamma
Normal
Constant 0.7162
(0.1319)
0.0000
0.4957(0.05463)
0.7628(0.07247)
–1.2354(0.1079)
0.0000
–0.6343(0.07328)
0.1169(0.06612)
Age
0.01844(0.001336)
0.03115(0.001443)
0.02329(0.0004458)
0.01803(0.0007916)
0.02389(0.001188)
0.04479(0.002769)
0.01899(0.0007820)
0.02231(0.0006969)
Educ
–0.03429(0.007255)
–0.03803(0.01733)
–0.03427(0.004352)
–0.03839(0.003965)
0.01652(0.006501)
–0.04589(0.02967)
–0.01779(0.004056)
–0.03773(0.003595)
Income
–0.4751(.08212)
–0.3030(0.04104)
–0.2646(0.01520)
–0.4206(0.04700)
0.02373(0.05530)
–0.1968(0.07320)
–0.08126(0.04565)
–0.1743(0.04273)
Kids
–0.1582(0.03115)
–0.001927(0.01546)
–0.03854(0.005272)
–0.1513(0.01738)
–0.03381(0.02116)
–0.001274(0.02920)
–0.1103(0.01675)
–0.1187(0.01582)
Public
0.2365(0.04307)
0.1015(0.02980)
0.1535(0.01268)
0.2324(0.02900)
0.05837(0.03896)
0.09700(0.05334)
0.1486(0.02834)
0.1940(0.02574)
θ
0.0000
0.0000
1.1646(0.01940)
1.9242(0.02008)
0.0000
1.9199(0.02994)
0.0000
1.0808(0.01203)
a
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
2.1463(0.05955)
0.0000
b
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
3.8011(0.1145)
0.0000
σ
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.9737(0.008235)
ln
L
–104440.3
–60337.13
–71763.13
–60265.49
–34016.16
–49476.36
–58182.52
–58177.66