摘要
本文针对年金管理,综合考虑死亡率随年龄和时间的变动规律,构建基于我国历史数据的Gaussian-Gompertz随机死亡率模型,采用Vasicek模型刻画短期利率风险,采用几何布朗运动随机模型刻画权益风险,采用资产负债比率变异系数、破产概率和偿付能力风险资本系数等指标度量风险。研究发现:个体波动性长寿风险通过扩大投保规模将得到有效分散;集体趋势性长寿风险随时间的延续不断积聚;长寿风险、利率风险与投资风险的综合影响会显著增加保险公司的风险水平,危及公司的偿付能力;相比长寿风险,利率风险和投资风险对偿付能力风险的影响更大。
This paper combines the evolutions of mortality with age and time for annuity management and establishes a Gaussian-Gompertz stochastic mortality model based on the historical data of mortalities in China. Moreover, the interest rate follows the Vasicek model and the equity risk is modeled by a geometric Brownian motion. Meanwhile, this paper assesses the risks by the coefficient of variance of funding ratio, probability of ruin and solvency capital requirement. The analysis show that:the individual volatility longevity risk can be efficiently eliminated by increasing the size of the annuity; the group tendency longevity risk accumulates with time continuously; the combination of longevity risk, interest risk and investment risk increases risks of the insurance company significantly and imperils the solvency of the company; compared to longevity risk, the effects of interest risk and investment risk on the risk level are larger.
引文
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