Institute of Social and Economic Research, Osaka University, 6-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan.
J Health Econ. 2010 Mar;29(2):268-84. doi: 10.1016/j.jhealeco.2010.01.002. Epub 2010 Jan 25.
Analysis of a broad survey of Japanese adults confirms that time discounting relates to body weight, not only via impatience, but also via hyperbolic discounting, proxied by inclination toward procrastination, and the sign effect, where future negative payoffs are discounted at a lower rate than future positive payoffs. Body mass index is positively associated with survey responses indicative of impatience and hyperbolic discounting, and negatively associated with those indicative of the sign effect. A one-unit increase in the degree of procrastination is associated with a 2.81 percentage-point increase in the probability of being obese. Subjects exhibiting the sign effect show a 3.69 percentage-point lower probability of being obese and a 4.02 percentage-point higher probability of being underweight than those without the sign effect. These effects are substantial compared with the prevalence rates of the corresponding body mass status. Obesity and underweight thus result in part from the temporal decision biases.
对日本成年人进行的广泛调查分析证实，时间贴现不仅与不耐烦有关，还与拖延倾向所代表的双曲线贴现以及未来负收益贴现率低于未来正收益贴现率的符号效应有关。体重指数与急躁和双曲线贴现的调查反应呈正相关，与符号效应的调查反应呈负相关。拖延程度每增加一个单位，肥胖的概率就会增加 2.81 个百分点。表现出符号效应的个体肥胖的概率比没有符号效应的个体低 3.69 个百分点，体重不足的概率高 4.02 个百分点。与相应体重状况的流行率相比，这些影响是相当大的。因此，肥胖和体重不足部分是由于时间决策偏差所致。
