Goyal Shruti, Miyapuram Krishna P
Centre for Cognitive and Brain Sciences, Indian Institute of Technology Gandhinagar, Gujarat, India.
Front Psychol. 2019 May 3;10:962. doi: 10.3389/fpsyg.2019.00962. eCollection 2019.
Our understanding of the decisions made under scenarios where both descriptive and experience-based information are available is very limited. Underweighting of small probabilities was observed in the gain domain when both description and experience were provided. The divergence observed from the prospect theory suggests a need for a separate or modified theory of decision making under risk. Recent studies suggest a possible role of probability weighting in the choice behavior under risk. We investigated both gain and loss domains with and without feedback for small and large probability conditions. We characterized the shape of the probability weighting function by a two-parameter functional form representing discriminability (concave-convex shape) and attractiveness (level of absolute weights relative to objective probability). We replicated a fourfold pattern of risk attitude on non-WEIRD population. We find that feedback leads to underweighting of small probabilities and overweighting of large probabilities in the gain domain and overall underweighting of probabilities in the loss domain. We find that underweighting of small probabilities is driven by changes in discriminability and attractiveness components in the gain domain and changes in the attractiveness component in the loss domain. We have interpreted the results by proposing an updated belief-based account of decisions under uncertainty in which feedback, when available, influences the probability weighting mediating the choice behavior.
我们对于在既有描述性信息又有基于经验的信息的情况下所做决策的理解非常有限。当同时提供描述和经验时，在收益领域观察到小概率被低估的情况。与前景理论的分歧表明需要一种单独的或经过修正的风险决策理论。最近的研究表明概率加权在风险下的选择行为中可能发挥作用。我们研究了有反馈和无反馈情况下小概率和大概率条件下的收益和损失领域。我们通过一个双参数函数形式来刻画概率加权函数的形状，该函数形式表示可辨别性（凹凸形状）和吸引力（相对于客观概率的绝对权重水平）。我们在非西方、工业化、富裕、民主（WEIRD）人群中重现了风险态度的四重模式。我们发现反馈导致收益领域中小概率被低估、大概率被高估，而损失领域中概率总体被低估。我们发现小概率被低估是由收益领域中可辨别性和吸引力成分的变化以及损失领域中吸引力成分的变化驱动的。我们通过提出一种更新的基于信念的不确定性决策解释来解读这些结果，在这种解释中，反馈（如果可用）会影响介导选择行为的概率加权。
