Table 8.
Probit Estimates: Reactions to Learning HIV Results
| Dependent variable: Bought any condoms | ||||
|---|---|---|---|---|
| OLS (1) | IV (2) | Probit (marginal effects) (3) | Bivariate probit (marginal effects) (4) | |
| Panel A: HIV positive | ||||
| Got results | 0.427*** (0.149) | 0.273 (0.200) | 0.437*** (0.138) | 0.370*** (0.141) |
| Male | 0.038 (0.115) | 0.024 (0.117) | 0.043 (0.129) | 0.026 (0.131) |
| Age | 0.001 (0.040) | −0.018 (0.043) | 0.004 (0.039) | −0.009 (0.038) |
| Age2 | 0.000 (0.001) | 0.000 (0.001) | 0.000 (0.000) | 0.000 (0.000) |
| Simulated average distance | 0.025 (0.074) | 0.026 (0.072) | 0.026 (0.074) | 0.025 (0.074) |
| Rumphi | −0.084 (0.179) | −0.08 (0.177) | −0.126 (0.195) | −0.117 (0.193) |
| Constant | 0.055 (0.823) | 0.511 (0.974) | ||
| Sample size | 52 | 52 | 52 | 52 |
| R2 | 0.21 | 0.18 | 0.18 | |
| Mean | 0.38 | 0.38 | 0.38 | 0.38 |
|
| ||||
| Panel B: HIV negative | ||||
| Got results | −0.023 (0.025) | −0.072 (0.061) | −0.033 (0.029) | −0.128 (0.088) |
| Male | 0.113*** (0.028) | 0.111*** (0.027) | 0.118*** (0.029) | 0.114*** (0.029) |
| Age | −0.007 (0.005) | −0.006 (0.005) | −0.005 (0.005) | −0.004 (0.005) |
| Age2 | 0.000 (0.000) | 0.000 (0.000) | 0.000 (0.000) | 0.000 (0.000) |
| Simulated average distance | −0.052** (0.022) | −0.053** (0.022) | −0.043** (0.018) | −0.044** (0.018) |
| Rumphi | −0.362*** (0.040) | −0.368*** (0.041) | −0.356*** (0.036) | −0.365*** (0.037) |
| Constant | 0.754*** (0.109) | 0.784*** (0.116) | ||
| Sample size | 956 | 956 | 956 | 956 |
| R2 | 0.19 | 0.19 | 0.18 | |
| Mean | 0.25 | 0.25 | 0.25 | 0.25 |
Notes: Sample includes HIV-positive and negative respondents in Balaka and Rumphi who were tested for HIV, were reinterviewed in 2005, and who had sex in 2004. Robust standard errors clustered by village (for 57 villages) with district fixed effects are in parentheses. Coefficients in column 1 are linear OLS estimates. Coefficients in column 2 are linear IV estimates where knowing HIV status is instrumented by having any nonzero incentive, the total amount of the incentive, total amount squared, distance from the HIV results center, distance-squared, and all terms interacted with gender. Column 3 presents marginal probit estimates, which do not control for endogenous selection into learning HIV results. Column 4 presents the marginal effects of a seemingly unrelated bivariate probit, controlling for endogenous selection into learning HIV results (see text).
Significantly different from zero at 99 percent confidence level.
Significantly different from zero at 95 percent confidence level.
Significantly different from zero at 90 percent confidence level.