University of Chicago and NBER, United States.
J Health Econ. 2012 Jan;31(1):35-49. doi: 10.1016/j.jhealeco.2011.12.006. Epub 2012 Jan 3.
Despite high rates of HIV in Sub-Saharan Africa, and the corresponding high mortality risk associated with risky sexual behavior, behavioral response has been limited. This paper explores three explanations for this: bias in OLS estimates, limited non-HIV life expectancy and limited knowledge. I find support for the first two. First, using a new instrumental variable strategy I find that OLS estimates of the relationship between risky sex and HIV are biased upwards, and IV estimates indicate reductions in risky behavior in response to the epidemic. Second, I find these reductions are larger for individuals who live in areas with higher life expectancy, suggesting high rates of non-HIV mortality suppress behavioral response; this is consistent with optimizing behavior. Using somewhat limited knowledge proxies, I find no evidence that areas with higher knowledge of the epidemic have greater behavior change.
尽管撒哈拉以南非洲地区的艾滋病毒感染率很高，与危险性行为相关的死亡率也很高，但行为反应却受到限制。本文探讨了对此的三种解释：OLS 估计的偏差、有限的非艾滋病毒预期寿命和有限的知识。我发现前两个解释有一定的支持。首先，我使用一种新的工具变量策略，发现 OLS 估计的危险性行为与艾滋病毒之间的关系存在向上的偏差，而 IV 估计表明，艾滋病毒流行会导致危险行为减少。其次，我发现对于那些生活在预期寿命较高地区的人来说，这种减少幅度更大，这表明高非艾滋病毒死亡率抑制了行为反应；这与优化行为是一致的。使用一些有限的知识代理，我发现没有证据表明对艾滋病了解更多的地区会有更大的行为改变。
