Changes in Risk and the Demand for Coinsurance for Economically Important Individuals

風險轉換與經濟重要性個人之共同保險需求

10.6545/JFS.202109_29(3).0002

陳姿穎(Tzu-Ying Chen)

stochastic dominance ； almost stochastic dominance ； demand for coinsurance ； 隨機優越 ； 幾乎隨機優越 ； 共同保險需求

財務金融學刊

29卷3期（2021 / 09 / 30）

61 - 90

英文

This paper provides the necessary and sufficient conditions such that economically important individuals, as suggested by Tsetlin et al. (2015), demand a higher coinsurance rate when they face a change in the underlying loss distribution. We further study this issue by classifying the changes in risk into: (1) an increase in the severity of loss, and (2) an increase in the probability of loss. Finally, we provide a numerical example to demonstrate the usefulness of the proposed approach.

本文以Tsetlin et al.（2015）定義之經濟重要性（economically important）個人，探討其在面臨損失分配改變時，保險需求提升的充分必要條件。接著進一步將風險變動的來源，劃分為以下兩個部分討論：第一部分是損失強度（severity of loss）增加，第二部分是損失機率（probability of loss）增加。最後，本文以數值範例說明主要定理之應用。

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