2018年10月10日（水）に、エラスムス大学ロッテルダム エラスムス・スクール・オブ・エコノミックスのProf. Han Bleichrodt（行動経済学教授）を講師にお招きして、HIAS Health第33回定例研究会を開催しました（一橋大学国際交流セミナーとの合同開催）。
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| 講演中のProf. Han Bleichrodt（エラスムス大学ロッテルダム） | 参加者の質問に答えるProf. Han Bleichrodt |
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| 会場の様子 | 参加者と |
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| 日時 | 2018年10月10日（水）18：00～19：30 |
| 会場 | 西キャンパス 第2研究館 5階 HIASセミナー室（517号室） |
| 報告者 | Prof. Han Bleichrodt, Professor of Behavioral Economics, Erasmus School of Economics, Erasmus University Rotterdam, the Netherlands |
| タイトル | Ambiguity preferences for health |
| 言語 | 英語 |
| 概要 | In most medical decisions, probabilities are ambiguous and not objectively known. Empirical evidence suggests that people's preferences are affected by ambiguity. Health economic analyses generally ignore ambiguity preferences and assume that they are the same as preferences under risk. We show how health preferences can be measured under ambiguity, and we compare them with health preferences under risk. We assume a general ambiguity model that includes many of the ambiguity models that have been proposed in the literature. For health gains, ambiguity preferences and risk preferences were indeed the same. For health losses, they differed with subjects being more pessimistic in decision under ambiguity. Utility and loss aversion were the same for risk and ambiguity. Our results imply that reducing the clinical ambiguity of health losses has more impact than reducing the ambiguity of health gains, that utilities elicited with known probabilities may not carry over to an ambiguous setting, and that ambiguity aversion may impact value of information analyses if losses are involved. These findings are highly relevant for medical decision making, because most medical interventions involve losses. |