虛擬實境中之跨期選擇：天氣的影響

Abstract

本研究利用虛擬實境（Virtual Reality, VR）頭戴裝置，探討天氣的視覺及聽覺刺激對跨期選擇的影響。我們進行了一項隨機對照試驗（Randomized Controlled Trial, RCT），讓受試者隨機暴露於虛擬晴天和雨天的環境中，並要求其在較早獲得較少報酬，與較晚獲得較多報酬之間進行選擇。本研究發現，晴天條件下的受試者選擇較早獲得較少報酬選項的比例，比在雨天條件下高出 7.4\\\\\\\\\\\\\\\\%，且此結果由資訊搜集行為中介。儘管晴天條件提升了情緒效價，但情緒效價並未顯著地中介天氣對跨期選擇的影響。此外，我們發現天氣條件的順序對情緒效價具有重要影響，從晴天轉為雨天導致情緒顯著下降，而反之則未發生。此研究不僅突顯了環境因素對決策行為的重要性，還挑戰了將天氣作為工具變數來研究可能與時間偏好有關的變數之間因果關係的方法。

This study investigates the impact of highly realistic, visually simulated weather conditions, along with auditory stimuli, on intertemporal choices using a Virtual Reality (VR) headset. We conducted a randomized controlled trial (RCT) in which subjects were randomly assigned to virtual environments simulating sunny or rainy weather and were asked to choose between receiving smaller, sooner rewards or larger, later rewards. The results show that subjects exposed to sunny conditions were 7.4\\\\\\\\\\\\\\\\% more likely to choose the smaller, sooner rewards compared to those in rainy conditions, and this effect was mediated by information-gathering behavior. Although sunny conditions increased emotional valence, emotional valence did not significantly mediate the effect of weather on intertemporal choices. Furthermore, we found that the sequence of weather conditions significantly influenced emotional valence: transitioning from sunny to rainy weather led to a marked decline in emotional valence, whereas the reverse transition did not have a significant effect. This study not only highlights the importance of environmental factors in decision-making but also challenges the use of weather as an instrumental variable for investigating causal relationships between variables that may be related to time preferences.