兩篇關於保險需求之論文

Two Essays on Demand for Coinsurance

陳姿穎(Tzu-Ying Chen)

指導教授 ： 曾郁仁

國立臺灣大學/管理學院/財務金融學研究所/博士(2021年)

https://doi.org/10.6342/NTU202100818

摘要

本論文由兩篇關於保險需求理論的文章所組成。在第一篇文章中，根據序列相依期望效用(rank-dependent expected utility)理論，我們提出了保險連接型樂透(insurance-linked lotto)商品，作為政府在保險市場中的政策工具。此一保險連接型樂透商品，與可保風險的發生與否無關，而是藉由樂透獎金或樂透中獎機率的設計機制，使其與個人保險需求量相連結。研究結果發現，若個人在不確定情況下的決策行為可以根據序列相依期望效用理論來描述，政府發行此一保險連接型樂透商品，不僅可以有效提升個人保險購買量，更可以進一步提升整體社會福祉。
在第二篇文章中，根據Tsetlin, Winkler, Huang and Tzeng (2015)所定義的經濟重要性(economically important)個人，當面臨之風險變動時，我們提出經濟重要性個人會提升保險購買量的充分必要條件。接著進一步將風險變動的來源，分為以下兩部分討論：第一部分是損失機率(probability of loss)的改變，第二部分是損失強度(severity of loss)的改變。最後，透過數值範例來說明主要定理之可行性。

關鍵字

序列相依期望效用 ； 樂透 ； 保險需求 ； 隨機優越 ； 幾乎隨機優越

並列摘要

Adopting advanced models in the literature of risk theory, my dissertation studies the demand for coinsurance and contains two essays. Notations defined in each chapter are applicable for that chapter only.
In the first chapter of my dissertation, inspired by the successful prediction of rank dependent expected utility (RDEU) theory on human behavior, I propose an insurance-linked lotto as a new tool of government intervention in insurance markets. The lotto is independent of the occurrence of the insurable risk, but the prize and/or the probability of winning the prize is dependent on the insurance demand. I show that when an individual's preference is characterized by RDEU, the insurance-linked lotto could improve social welfare and enhance the equilibrium demand for insurance.
In the second chapter of my dissertation, I provide the necessary and sufficient conditions such that economically important individuals, as suggested by Tsetlin, Winkler, Huang and Tzeng (2015), demand a higher coinsurance rate when they face a change in risk. I further study this issue by classifying the changes in risk into: (1) an increase in the probability of loss, and (2) an increase in the severity of loss. Finally, I provide a numerical example to demonstrate the usefulness of the proposed approach.

並列關鍵字

Rank dependent expected utility ； lotto ； demand for insurance ； stochastic dominance ； almost stochastic dominance

參考文獻

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