Table 4.
Model | Probit Regression Coefficient | Odds Ratio [95% CI] | 1st IV condition X2/F [df] | 2nd IV condition X2 [df] | Exogenous Cigarettes X2 [1] |
---|---|---|---|---|---|
Excluding OTHER_BEHAVIOR | |||||
Probit | 0.013* (0.007) | 1.21* [0.99,1.51] | |||
CML-IV probit – Instrument Specification 1 | 0.099*** (0.030) | 4.2** [1.01,9.13] | 24.52*** [8] | 3.08 [7]; p=0.88 | 5.33** |
Two stage IV probit – Instrument Specification 1 | 0.11** (0.04) | 3.82** [1.09,7.13] | 3.3*** [8, 829] | 4.98** | |
CML-IV probit under alternative instrument specifications | |||||
Instrument Specification 2 | 0.11*** (0.03) | 4.73** [1.13,8.17] | 21.8*** [5] | 2.45 [4]; p = 0.65 | 6.24** |
Instrument Specification 3 | 0.11*** (0.03) | 4.59* [0.94,8.19] | 19.19*** [6] | 2.88 [5]; p= 0.72 | 5.00** |
Instrument Specification 4 | 0.11*** (0.03) | 4.82* [0.96,8.32] | 17.42*** [4] | 2.45 [3]; p= 0.48 | 5.14** |
Note: The models are based on a sample size of 856 observations. Standard errors of regression coefficients are in parentheses. The 95% confidence bounds of the odds ratio estimates are in brackets. The first IV condition column reports a chisquare test of the joint significance of the instruments in the cigarettes function (degrees of freedom [df] in brackets). The second IV condition reports the over-identification chi-square test (df in brackets).
p < 0.1,
p < 0.05,
p < 0.01.