变利率下基于CEV模型的最优再保险-投资策略Optimal Reinsurance-investment Strategy Based on CEV Model Under Variable Interest Rate
徐文静,夏登峰,杨铭,韩雪伟
摘要(Abstract):
假设保险公司的盈余过程由跳扩散风险模型来刻画。为了保值增值,保险公司购买超额损失再保险来降低自身风险,同时将其盈余投资于金融市场中的无风险资产和风险资产。其中,无风险资产的利率服从Vasicek利率模型,风险资产价格遵循CEV模型。保险公司的目标是终端财富的期望指数效用最大化。接着,应用随机最优控制的方法建立了值函数相应的HJB方程,并在指数效用函数下求解得到最优策略。最后,运用数值算例方法阐述了模型参数对最优策略的影响。研究结果说明风险厌恶系数和利率风险对最优策略的影响较大。
关键词(KeyWords): 超额损失再保险;随机利率;跳-扩散模型;CEV模型;HJB方程
基金项目(Foundation): 安徽省高校自然科学研究重点项目(KJ2021A0514)
作者(Author): 徐文静,夏登峰,杨铭,韩雪伟
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