How soon is now? Evidence of present bias from convex time budget experiments
在肯尼亚进行实验室实验，用凸时间预算方法测量494名参与者的时间和风险偏好，发现当日立即支付时存在现时偏误，参数估计在0.902到0.924之间。
Abstract We conduct a laboratory experiment in Kenya in which we elicit time and risk preference parameters from 494 participants, using convex time budgets and tightly controlling for transaction costs. Using the Kenyan mobile money system M-Pesa to make real-time transfers to subjects’ phones , we vary whether same-day payments are made immediately after the experimental session or at the close of the business day. We find strong evidence of present bias, with estimates of the present bias parameter ranging from 0.902 to 0.924—but only when same-day payments are made immediately after the experiment.