不對稱訊息在台灣車體保險市場之研究

Abstract

本論文實證研究台灣車體損失保險資訊不對稱的現象，根據Chiappori and Salanié (2000)模型，實證結果發現保險公司與投保人之間存在資訊不對稱的現象。然而我們的模型實證結果支持，在控制保費價格後，保障高低和理賠發生與否並不相關，此一現象在高理賠金額部分更明顯。我們的研究結果支持：利用保費調整，台灣目前購買車體險的投保人與保險公司之間，特別在高金額理賠部分，保險公司似乎有效地控制資訊不對稱問題。然而從整體市場來看，調高保費後，由於投保比例大幅下降，我們的研究結果認為整個車體險的市場，可能仍存在嚴重的資訊不對稱問題有待解決。

The paper extends Chiappori and Salanie (2000) to analyze asymmetric information problems in Taiwan’s automobile physical damage insurance market. By using alternative paired proit models, we first investigate whether asymmetric information exists in the market. We further examine whether insurance companies can use pricing system to control asymmetric information problems. Finally, we test whether asymmetric information problems are mainly contributed by small claims, which could be an empirical evidence to argue that the underwriting and auditing systems of insurance companies may help to control asymmetric information problems. Chiappori and Salanie (2000) found no empirical support for the existence of asymmetric information in the liability insurance market of France. On the contrary, we find strong empirical evidence to support the existence of asymmetric information in Taiwan’s automobile physical damage insurance market. Our paper demonstrates a further need for the research which tests the existence of asymmetric information by using data from different markets as well as different countries. Moreover, we find that insurance companies could somehow control the asymmetric information problems by their pricing, underwriting, and auditing systems. We find that, after controlling insurance premium, the conditional correlation of policy choices and claims is not significantly different from zero. Furthermore, we find that the conditional correlation of policy choices and claims decreases with respective to an increase of monetary threshold of claims. Although we find that the asymmetric information problems between the insured and the insurer seems under control by insurance companies, we observe that the population who purchase automobile physical damage insurance has decreased dramatically since 1995. This evidence supports that automobile physical damage insurance market may need further reformed to cope with asymmetric information problems.