首页 > 最新文献

Annals of Actuarial Science最新文献

英文 中文
An assessment of model risk in pricing wind derivatives 风衍生品定价模型风险评估
Q3 BUSINESS, FINANCE Pub Date : 2023-09-21 DOI: 10.1017/s1748499523000192
Giovani Gracianti, Rui Zhou, Johnny Siu-Hang Li, Xueyuan Wu
Abstract Wind derivatives are financial instruments designed to mitigate losses caused by adverse wind conditions. With the rapid growth of wind power capacity due to efforts to reduce carbon emissions, the demand for wind derivatives to manage uncertainty in wind power production is expected to increase. However, existing wind derivative literature often assumes normally distributed wind speed, despite the presence of skewness and leptokurtosis in historical wind speed data. This paper investigates how the misspecification of wind speed models affects wind derivative prices and proposes the use of the generalized hyperbolic distribution to account for non-normality. The study develops risk-neutral approaches for pricing wind derivatives using the conditional Esscher transform, which can accommodate stochastic processes with any distribution, provided the moment-generating function exists. The analysis demonstrates that model risk varies depending on the choice of the underlying index and the derivative’s payoff structure. Therefore, caution should be exercised when choosing wind speed models. Essentially, model risk cannot be ignored in pricing wind speed derivatives.
风衍生品是旨在减轻不利风条件造成的损失的金融工具。由于减少碳排放的努力,风力发电容量迅速增长,预计对风力衍生产品的需求将增加,以管理风力发电的不确定性。然而,尽管历史风速数据存在偏态和细峰态,但现有的风导数文献通常假设风速为正态分布。本文研究了风速模型的错误规范如何影响风衍生品价格,并提出使用广义双曲分布来解释非正态性。本研究利用条件Esscher变换开发了风衍生品定价的风险中性方法,该方法可以适应任何分布的随机过程,只要存在矩生成函数。分析表明,模型风险随标的指数的选择和衍生品的收益结构而变化。因此,在选择风速模型时应谨慎。在风速衍生品定价中,模型风险是不可忽视的。
{"title":"An assessment of model risk in pricing wind derivatives","authors":"Giovani Gracianti, Rui Zhou, Johnny Siu-Hang Li, Xueyuan Wu","doi":"10.1017/s1748499523000192","DOIUrl":"https://doi.org/10.1017/s1748499523000192","url":null,"abstract":"Abstract Wind derivatives are financial instruments designed to mitigate losses caused by adverse wind conditions. With the rapid growth of wind power capacity due to efforts to reduce carbon emissions, the demand for wind derivatives to manage uncertainty in wind power production is expected to increase. However, existing wind derivative literature often assumes normally distributed wind speed, despite the presence of skewness and leptokurtosis in historical wind speed data. This paper investigates how the misspecification of wind speed models affects wind derivative prices and proposes the use of the generalized hyperbolic distribution to account for non-normality. The study develops risk-neutral approaches for pricing wind derivatives using the conditional Esscher transform, which can accommodate stochastic processes with any distribution, provided the moment-generating function exists. The analysis demonstrates that model risk varies depending on the choice of the underlying index and the derivative’s payoff structure. Therefore, caution should be exercised when choosing wind speed models. Essentially, model risk cannot be ignored in pricing wind speed derivatives.","PeriodicalId":44135,"journal":{"name":"Annals of Actuarial Science","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136129646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Individual life insurance during epidemics 流行病期间的个人人寿保险
Q3 BUSINESS, FINANCE Pub Date : 2023-09-13 DOI: 10.1017/s1748499523000209
Laura Francis, Mogens Steffensen
Abstract The coronavirus pandemic has created a new awareness of epidemics, and insurance companies have been reminded to consider the risk related to infectious diseases. This paper extends the traditional multi-state models to include epidemic effects. The main idea is to specify the transition intensities in a Markov model such that the impact of contagion is explicitly present in the same way as in epidemiological models. Since we can study the Markov model with contagious effects at an individual level, we consider individual risk and reserves relating to insurance products, conforming with the standard multi-state approach in life insurance mathematics. We compare our notions with other but related notions in the literature and perform numerical illustrations.
新型冠状病毒大流行让人们对流行病有了新的认识,也提醒保险公司考虑与传染病相关的风险。本文扩展了传统的多状态模型,使其包含了流行病的影响。主要思想是在马尔可夫模型中指定过渡强度,以便传染的影响以与流行病学模型相同的方式明确呈现。由于我们可以在个体水平上研究具有传染效应的马尔可夫模型,因此我们考虑了与保险产品相关的个体风险和准备金,符合人寿保险数学中的标准多状态方法。我们将我们的概念与文献中其他相关概念进行比较,并进行数值说明。
{"title":"Individual life insurance during epidemics","authors":"Laura Francis, Mogens Steffensen","doi":"10.1017/s1748499523000209","DOIUrl":"https://doi.org/10.1017/s1748499523000209","url":null,"abstract":"Abstract The coronavirus pandemic has created a new awareness of epidemics, and insurance companies have been reminded to consider the risk related to infectious diseases. This paper extends the traditional multi-state models to include epidemic effects. The main idea is to specify the transition intensities in a Markov model such that the impact of contagion is explicitly present in the same way as in epidemiological models. Since we can study the Markov model with contagious effects at an individual level, we consider individual risk and reserves relating to insurance products, conforming with the standard multi-state approach in life insurance mathematics. We compare our notions with other but related notions in the literature and perform numerical illustrations.","PeriodicalId":44135,"journal":{"name":"Annals of Actuarial Science","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135740470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
An uncertainty-based risk management framework for climate change risk 基于不确定性的气候变化风险管理框架
IF 1.7 Q3 BUSINESS, FINANCE Pub Date : 2023-09-05 DOI: 10.1017/s1748499523000179
Rüdiger Kiesel, Gerhard Stahl
Climate risks are systemic risks and may be clustered according to so-called volatilities, uncertainties, complexities, and ambiguities (VUCA) criteria. We analyze climate risk in the VUCA concept and provide a framework that allows to interpret systemic risks as model risk. As climate risks are characterized by deep uncertainties (unknown unknowns), we argue that precautionary and resilient principles should be applied instead of capital-based risk measures (reasonable for known unknows). A prominent example of the proposed principles is the precommitment approach (PCA). Within the PCA, subjective probabilities allow to discriminate between tolerable risks and acceptable ones. The amount of determined solvency capital for acceptable risks and estimations of model risk may be aggregated by means of a multiplier approach. This framework is in line with the three-pillar approach of Solvency II, especially with the recovery and resolution plan. Furthermore, it fits smoothly to a hybrid approach of micro- and macroprudential supervision.
气候风险是系统性风险,可以根据所谓的波动性、不确定性、复杂性和模糊性(VUCA)标准进行聚类。我们分析了VUCA概念中的气候风险,并提供了一个框架,允许将系统性风险解释为模型风险。由于气候风险具有深刻的不确定性(未知的未知),我们认为应该采用预防和弹性原则,而不是基于资本的风险措施(对于已知的未知是合理的)。提出的原则的一个突出例子是预承诺方法(PCA)。在PCA中,主观概率允许区分可容忍的风险和可接受的风险。可接受风险的确定偿付能力资本数额和模型风险的估计可以用乘数法加以汇总。该框架符合《偿付能力II》的三支柱方法,特别是与复苏和处置计划相一致。此外,它还能很好地适应微观和宏观审慎监管的混合方法。
{"title":"An uncertainty-based risk management framework for climate change risk","authors":"Rüdiger Kiesel, Gerhard Stahl","doi":"10.1017/s1748499523000179","DOIUrl":"https://doi.org/10.1017/s1748499523000179","url":null,"abstract":"\u0000 Climate risks are systemic risks and may be clustered according to so-called volatilities, uncertainties, complexities, and ambiguities (VUCA) criteria. We analyze climate risk in the VUCA concept and provide a framework that allows to interpret systemic risks as model risk. As climate risks are characterized by deep uncertainties (unknown unknowns), we argue that precautionary and resilient principles should be applied instead of capital-based risk measures (reasonable for known unknows). A prominent example of the proposed principles is the precommitment approach (PCA). Within the PCA, subjective probabilities allow to discriminate between tolerable risks and acceptable ones. The amount of determined solvency capital for acceptable risks and estimations of model risk may be aggregated by means of a multiplier approach. This framework is in line with the three-pillar approach of Solvency II, especially with the recovery and resolution plan. Furthermore, it fits smoothly to a hybrid approach of micro- and macroprudential supervision.","PeriodicalId":44135,"journal":{"name":"Annals of Actuarial Science","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48990961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Lapse risk modeling in insurance: a Bayesian mixture approach 保险中的失误风险建模:一种贝叶斯混合方法
IF 1.7 Q3 BUSINESS, FINANCE Pub Date : 2023-09-01 DOI: 10.1017/s1748499523000180
Viviana G. R. Lobo, Thaís C. O. Fonseca, M. Alves
This paper focuses on modeling surrender time for policyholders in the context of life insurance. In this setup, a large lapse rate at the first months of a contract is often observed, with a decrease in this rate after some months. The modeling of the time to cancelation must account for this specific behavior. Another stylized fact is that policies which are not canceled in the study period are considered censored. To account for both censoring and heterogeneous lapse rates, this work assumes a Bayesian survival model with a mixture of regressions. The inference is based on data augmentation allowing for fast computations even for datasets of over millions of clients. Moreover, frequentist point estimation based on Expectation–Maximization algorithm is also presented. An illustrative example emulates a typical behavior for life insurance contracts, and a simulated study investigates the properties of the proposed model. A case study is considered and illustrates the flexibility of our proposed model allowing different specifications of mixture components. In particular, the observed censoring in the insurance context might be up to $50%$ of the data, which is very unusual for survival models in other fields such as epidemiology. This aspect is exploited in our simulated study.
本文主要研究人寿保险背景下投保人的退保时间模型。在这种设置中,通常在合同的前几个月观察到较大的失效率,几个月后该失效率会下降。取消时间的建模必须考虑到这种特定的行为。另一个程式化的事实是,在研究期间没有取消的政策被视为审查。为了考虑审查率和异质失效率,这项工作假设了一个混合回归的贝叶斯生存模型。该推断基于数据扩充,即使对于数百万客户端的数据集也可以进行快速计算。此外,还提出了基于期望-最大化算法的频率点估计。一个示例模拟了人寿保险合同的典型行为,并对所提出的模型的性质进行了模拟研究。通过一个案例研究,说明了我们提出的模型的灵活性,允许不同规格的混合物成分。特别是,在保险背景下观察到的审查可能高达数据的50%,这对于流行病学等其他领域的生存模型来说是非常不寻常的。在我们的模拟研究中利用了这一方面。
{"title":"Lapse risk modeling in insurance: a Bayesian mixture approach","authors":"Viviana G. R. Lobo, Thaís C. O. Fonseca, M. Alves","doi":"10.1017/s1748499523000180","DOIUrl":"https://doi.org/10.1017/s1748499523000180","url":null,"abstract":"\u0000 This paper focuses on modeling surrender time for policyholders in the context of life insurance. In this setup, a large lapse rate at the first months of a contract is often observed, with a decrease in this rate after some months. The modeling of the time to cancelation must account for this specific behavior. Another stylized fact is that policies which are not canceled in the study period are considered censored. To account for both censoring and heterogeneous lapse rates, this work assumes a Bayesian survival model with a mixture of regressions. The inference is based on data augmentation allowing for fast computations even for datasets of over millions of clients. Moreover, frequentist point estimation based on Expectation–Maximization algorithm is also presented. An illustrative example emulates a typical behavior for life insurance contracts, and a simulated study investigates the properties of the proposed model. A case study is considered and illustrates the flexibility of our proposed model allowing different specifications of mixture components. In particular, the observed censoring in the insurance context might be up to \u0000 \u0000 \u0000 \u0000$50%$\u0000\u0000 \u0000 of the data, which is very unusual for survival models in other fields such as epidemiology. This aspect is exploited in our simulated study.","PeriodicalId":44135,"journal":{"name":"Annals of Actuarial Science","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49468786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Plant growth stages and weather index insurance design 植物生长阶段与天气指数保险设计
IF 1.7 Q3 BUSINESS, FINANCE Pub Date : 2023-08-03 DOI: 10.1017/s1748499523000167
Jing Zou, M. Odening, Ostap Okhrin
Given the assumption that weather risks affect crop yields, we designed a weather index insurance product for soybean producers in the US state of Illinois. By separating the entire vegetation cycle into four growth stages, we investigate whether the phase-division procedure contributes to weather–yield loss relation estimation and, hence, to basis risk mitigation. Concretely, supposing stage-variant interaction patterns between temperature-based weather index growing degree days and rainfall-based weather index cumulative rainfall, a nonparametric weather–yield loss relation is estimated by a generalized additive model. The model includes penalized B-spline (P-spline) approach based on nonlinear optimal indemnity solutions under the expected utility framework. The P-spline analysis of variance (PS-ANOVA) method is used for efficient estimation through mixed model re-parameterization. The results indicate that the phase-division models significantly outperform the benchmark whole-cycle ones either under quadratic utility or exponential utility, given different levels of risk aversions. Finally, regarding hedging effectiveness, the expected utility ratio between the phase-division contract and the whole-cycle contract, and the percentage changes of mean root square loss and variance of revenues support the proposed phase-division contract.
假设天气风险影响作物产量,我们为美国伊利诺伊州的大豆生产者设计了一种天气指数保险产品。通过将整个植被周期划分为四个生长阶段,我们研究了阶段划分程序是否有助于天气-产量损失关系估计,从而有助于基础风险缓解。具体而言,假设基于温度的天气指数增温日数与基于降雨量的天气指数累积降雨量之间存在阶段性的相互作用模式,利用广义加性模型估计了非参数天气-产量损失关系。该模型采用基于期望效用框架下非线性最优补偿解的惩罚b样条(p样条)方法。采用p样条方差分析(PS-ANOVA)方法,通过混合模型再参数化进行有效估计。结果表明,在风险厌恶程度不同的情况下,分相模型在二次效用和指数效用下均显著优于基准全周期模型。最后,在套期保值有效性方面,分阶段合约与全周期合约之间的预期效用比、均方根损失和收益方差的百分比变化均支持建议的分阶段合约。
{"title":"Plant growth stages and weather index insurance design","authors":"Jing Zou, M. Odening, Ostap Okhrin","doi":"10.1017/s1748499523000167","DOIUrl":"https://doi.org/10.1017/s1748499523000167","url":null,"abstract":"\u0000 Given the assumption that weather risks affect crop yields, we designed a weather index insurance product for soybean producers in the US state of Illinois. By separating the entire vegetation cycle into four growth stages, we investigate whether the phase-division procedure contributes to weather–yield loss relation estimation and, hence, to basis risk mitigation. Concretely, supposing stage-variant interaction patterns between temperature-based weather index growing degree days and rainfall-based weather index cumulative rainfall, a nonparametric weather–yield loss relation is estimated by a generalized additive model. The model includes penalized B-spline (P-spline) approach based on nonlinear optimal indemnity solutions under the expected utility framework. The P-spline analysis of variance (PS-ANOVA) method is used for efficient estimation through mixed model re-parameterization. The results indicate that the phase-division models significantly outperform the benchmark whole-cycle ones either under quadratic utility or exponential utility, given different levels of risk aversions. Finally, regarding hedging effectiveness, the expected utility ratio between the phase-division contract and the whole-cycle contract, and the percentage changes of mean root square loss and variance of revenues support the proposed phase-division contract.","PeriodicalId":44135,"journal":{"name":"Annals of Actuarial Science","volume":"1 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42113444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Portfolio management for insurers and pension funds and COVID-19: targeting volatility for equity, balanced, and target-date funds with leverage constraints 针对保险公司、养老基金和COVID-19的投资组合管理:针对杠杆限制下的股票、平衡基金和目标日期基金的波动性
IF 1.7 Q3 BUSINESS, FINANCE Pub Date : 2023-07-11 DOI: 10.1017/s1748499523000143
Bao Doan, Jonathan J. Reeves, Michael Sherris
Insurers and pension funds face the challenges of historically low-interest rates and high volatility in equity markets, that have been accentuated due to the COVID-19 pandemic. Recent advances in equity portfolio management with a target volatility have been shown to deliver improved on average risk-adjusted return, after transaction costs. This paper studies these targeted volatility portfolios in applications to equity, balanced, and target-date funds with varying constraints on leverage. Conservative leverage constraints are particularly relevant to pension funds and insurance companies, with more aggressive leverage levels appropriate for alternative investments. We show substantial improvements in fund performance for differing leverage levels, and of most interest to insurers and pension funds, we show that the highest Sharpe ratios and smallest drawdowns are in targeted volatility-balanced portfolios with equity and bond allocations. Furthermore, we demonstrate the outperformance of targeted volatility portfolios during major stock market crashes, including the crash from the COVID-19 pandemic.
保险公司和养老基金面临着历史上低利率和股票市场高度波动的挑战,这些挑战因COVID-19大流行而加剧。具有目标波动率的股票投资组合管理的最新进展已被证明,在扣除交易成本后,可提供更高的经风险调整后的平均回报。本文研究了这些目标波动率组合在不同杠杆约束下的股票基金、平衡基金和目标日期基金中的应用。保守的杠杆限制与养老基金和保险公司尤其相关,更激进的杠杆水平适合另类投资。我们展示了不同杠杆水平下基金业绩的显著改善,保险公司和养老基金最感兴趣的是,我们展示了最高的夏普比率和最小的回撤是在股票和债券配置的目标波动性平衡投资组合中。此外,我们还证明了在重大股市崩盘期间,包括COVID-19大流行造成的崩盘期间,目标波动率投资组合的表现优于其他投资组合。
{"title":"Portfolio management for insurers and pension funds and COVID-19: targeting volatility for equity, balanced, and target-date funds with leverage constraints","authors":"Bao Doan, Jonathan J. Reeves, Michael Sherris","doi":"10.1017/s1748499523000143","DOIUrl":"https://doi.org/10.1017/s1748499523000143","url":null,"abstract":"Insurers and pension funds face the challenges of historically low-interest rates and high volatility in equity markets, that have been accentuated due to the COVID-19 pandemic. Recent advances in equity portfolio management with a target volatility have been shown to deliver improved on average risk-adjusted return, after transaction costs. This paper studies these targeted volatility portfolios in applications to equity, balanced, and target-date funds with varying constraints on leverage. Conservative leverage constraints are particularly relevant to pension funds and insurance companies, with more aggressive leverage levels appropriate for alternative investments. We show substantial improvements in fund performance for differing leverage levels, and of most interest to insurers and pension funds, we show that the highest Sharpe ratios and smallest drawdowns are in targeted volatility-balanced portfolios with equity and bond allocations. Furthermore, we demonstrate the outperformance of targeted volatility portfolios during major stock market crashes, including the crash from the COVID-19 pandemic.","PeriodicalId":44135,"journal":{"name":"Annals of Actuarial Science","volume":"19 3","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138509571","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Insurance as an ergodicity problem 保险是一个遍历性问题
IF 1.7 Q3 BUSINESS, FINANCE Pub Date : 2023-07-01 DOI: 10.1017/s1748499523000131
O. Peters
In November 2014, the economist Ken Arrow and I had one of our long conversations about my efforts to re-imagine economic science from the perspective of the ergodicity problem (Peters, 2019). Ergodicity, as it pertains to economics, is about two different ways of averaging to deal with randomness. Let us say we measure some quantity at regularly spaced times t = 1 . . . T and model it as a stochastic process, x(t,ω), where ω denotes the realization of the process. If we want to reduce the process to a single informative number, we can average across the ensemble of realizations, yielding the expected value E [x] (t)= limN→∞ 1 N ∑N i x(t,ωi), or we can average across time, yielding the time average T [x] (ω)= limT→∞ 1 T ∑T t x(t,ωi), Fig. 1. If the process is ergodic, then the two ways of averaging will give the same result. We are interested in cases where this is not true.
2014年11月,经济学家肯·阿罗(Ken Arrow)和我就我从遍历性问题的角度重新构想经济科学的努力进行了一次长谈(Peters, 2019)。在经济学中,遍历性是关于处理随机性的两种不同的平均方法。假设我们在规则间隔时间t = 1处测量某个量…T,并将其建模为随机过程x(T,ω),其中ω表示该过程的实现。如果我们想将过程简化为单个信息数,我们可以对实现集合进行平均,得到期望值E [x] (t)= limN→∞1 N∑N i x(t,ωi),或者我们可以对时间进行平均,得到时间平均值t [x] (ω)= limT→∞1 t∑t x(t,ωi),如图1所示。如果过程是遍历的,那么两种平均方法将得到相同的结果。我们感兴趣的是它不成立的情况。
{"title":"Insurance as an ergodicity problem","authors":"O. Peters","doi":"10.1017/s1748499523000131","DOIUrl":"https://doi.org/10.1017/s1748499523000131","url":null,"abstract":"In November 2014, the economist Ken Arrow and I had one of our long conversations about my efforts to re-imagine economic science from the perspective of the ergodicity problem (Peters, 2019). Ergodicity, as it pertains to economics, is about two different ways of averaging to deal with randomness. Let us say we measure some quantity at regularly spaced times t = 1 . . . T and model it as a stochastic process, x(t,ω), where ω denotes the realization of the process. If we want to reduce the process to a single informative number, we can average across the ensemble of realizations, yielding the expected value E [x] (t)= limN→∞ 1 N ∑N i x(t,ωi), or we can average across time, yielding the time average T [x] (ω)= limT→∞ 1 T ∑T t x(t,ωi), Fig. 1. If the process is ergodic, then the two ways of averaging will give the same result. We are interested in cases where this is not true.","PeriodicalId":44135,"journal":{"name":"Annals of Actuarial Science","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43824770","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Some comments on “A Hermite spline approach for modelling population mortality” by Tang, Li & Tickle (2022) 唐,李和蒂克尔(2022)对“人口死亡率建模的埃尔米特样条方法”的一些评论
IF 1.7 Q3 BUSINESS, FINANCE Pub Date : 2023-06-13 DOI: 10.1017/s174849952300012x
S. Richards
Tang et al. (2022) propose a new class of models for stochastic mortality modelling using Hermite splines. There are four useful features of this class that are worth emphasising. First, for single-sex datasets, this new class of projection models can be fitted as a generalised linear model. Second, these models can automatically extrapolate mortality rates to ages above the maximum age of the data set. Third, simpler sub-variants of the models exist for forecasting when one of the variables lacks a clear drift. Finally, a minor reparameterisation increases the quality of long-range forecasts of period mortality.
唐等人(2022)提出了一类使用埃尔米特样条进行随机死亡率建模的新模型。这个类有四个有用的特性值得强调。首先,对于单性别数据集,这类新的投影模型可以拟合为广义线性模型。其次,这些模型可以自动将死亡率外推到数据集最大年龄以上的年龄。第三,当其中一个变量缺乏明显的漂移时,存在用于预测的模型的更简单的子变量。最后,一个小的重新特征化提高了长期预测周期死亡率的质量。
{"title":"Some comments on “A Hermite spline approach for modelling population mortality” by Tang, Li & Tickle (2022)","authors":"S. Richards","doi":"10.1017/s174849952300012x","DOIUrl":"https://doi.org/10.1017/s174849952300012x","url":null,"abstract":"\u0000 Tang et al. (2022) propose a new class of models for stochastic mortality modelling using Hermite splines. There are four useful features of this class that are worth emphasising. First, for single-sex datasets, this new class of projection models can be fitted as a generalised linear model. Second, these models can automatically extrapolate mortality rates to ages above the maximum age of the data set. Third, simpler sub-variants of the models exist for forecasting when one of the variables lacks a clear drift. Finally, a minor reparameterisation increases the quality of long-range forecasts of period mortality.","PeriodicalId":44135,"journal":{"name":"Annals of Actuarial Science","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47227766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Neural networks for quantile claim amount estimation: a quantile regression approach 分位数索赔金额估计的神经网络:一种分位数回归方法
IF 1.7 Q3 BUSINESS, FINANCE Pub Date : 2023-05-17 DOI: 10.1017/s1748499523000106
Alessandro G. Laporta, Susanna Levantesi, L. Petrella
In this paper, we discuss the estimation of conditional quantiles of aggregate claim amounts for non-life insurance embedding the problem in a quantile regression framework using the neural network approach. As the first step, we consider the quantile regression neural networks (QRNN) procedure to compute quantiles for the insurance ratemaking framework. As the second step, we propose a new quantile regression combined actuarial neural network (Quantile-CANN) combining the traditional quantile regression approach with a QRNN. In both cases, we adopt a two-part model scheme where we fit a logistic regression to estimate the probability of positive claims and the QRNN model or the Quantile-CANN for the positive outcomes. Through a case study based on a health insurance dataset, we highlight the overall better performances of the proposed models with respect to the classical quantile regression one. We then use the estimated quantiles to calculate a loaded premium following the quantile premium principle, showing that the proposed models provide a better risk differentiation.
在本文中,我们讨论了使用神经网络方法将问题嵌入分位数回归框架中的非人寿保险总索赔金额的条件分位数的估计。作为第一步,我们考虑分位数回归神经网络(QRNN)程序来计算保险费率制定框架的分位数。作为第二步,我们将传统的分位数回归方法与QRNN相结合,提出了一种新的分位数-回归组合精算神经网络(quantile CANN)。在这两种情况下,我们都采用了两部分模型方案,其中我们拟合逻辑回归来估计积极索赔的概率,并拟合QRNN模型或Quantile CANN来估计积极结果。通过基于健康保险数据集的案例研究,我们强调了所提出的模型相对于经典分位数回归模型的总体性能更好。然后,我们根据分位数保费原则,使用估计的分位数来计算负载保费,表明所提出的模型提供了更好的风险区分。
{"title":"Neural networks for quantile claim amount estimation: a quantile regression approach","authors":"Alessandro G. Laporta, Susanna Levantesi, L. Petrella","doi":"10.1017/s1748499523000106","DOIUrl":"https://doi.org/10.1017/s1748499523000106","url":null,"abstract":"\u0000 In this paper, we discuss the estimation of conditional quantiles of aggregate claim amounts for non-life insurance embedding the problem in a quantile regression framework using the neural network approach. As the first step, we consider the quantile regression neural networks (QRNN) procedure to compute quantiles for the insurance ratemaking framework. As the second step, we propose a new quantile regression combined actuarial neural network (Quantile-CANN) combining the traditional quantile regression approach with a QRNN. In both cases, we adopt a two-part model scheme where we fit a logistic regression to estimate the probability of positive claims and the QRNN model or the Quantile-CANN for the positive outcomes. Through a case study based on a health insurance dataset, we highlight the overall better performances of the proposed models with respect to the classical quantile regression one. We then use the estimated quantiles to calculate a loaded premium following the quantile premium principle, showing that the proposed models provide a better risk differentiation.","PeriodicalId":44135,"journal":{"name":"Annals of Actuarial Science","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49179332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Package AdvEMDpy: Algorithmic variations of empirical mode decomposition in Python AdvEMDpy包:Python中经验模式分解的算法变化
Q3 BUSINESS, FINANCE Pub Date : 2023-05-05 DOI: 10.1017/s1748499523000088
Cole van Jaarsveldt, Matthew Ames, Gareth W. Peters, Mike Chantler
Abstract This work presents a $textsf{Python}$ EMD package named AdvEMDpy that is both more flexible and generalises existing empirical mode decomposition (EMD) packages in $textsf{Python}$ , $textsf{R}$ , and $textsf{MATLAB}$ . It is aimed specifically for use by the insurance and financial risk communities, for applications such as return modelling, claims modelling, and life insurance applications with a particular focus on mortality modelling. AdvEMDpy both expands upon the EMD options and methods available, and improves their statistical robustness and efficiency, providing a robust, usable, and reliable toolbox. Unlike many EMD packages, AdvEMDpy allows customisation by the user, to ensure that a broader class of linear, non-linear, and non-stationary time series analyses can be performed. The intrinsic mode functions (IMFs) extracted using EMD contain complex multi-frequency structures which warrant maximum algorithmic customisation for effective analysis. A major contribution of this package is the intensive treatment of the EMD edge effect which is the most ubiquitous problem in EMD and time series analysis. Various EMD techniques, of varying intricacy from numerous works, have been developed, refined, and, for the first time, compiled in AdvEMDpy . In addition to the EMD edge effect, numerous pre-processing, post-processing, detrended fluctuation analysis (localised trend estimation) techniques, stopping criteria, spline methods, discrete-time Hilbert transforms (DTHT), knot point optimisations, and other algorithmic variations have been incorporated and presented to the users of AdvEMDpy . This paper and the supplementary materials provide several real-world actuarial applications of this package for the user’s benefit.
本工作提出了一个名为AdvEMDpy的$textsf{Python}$ EMD包,它既灵活又推广了$textsf{Python}$、$textsf{R}$和$textsf{MATLAB}$中现有的经验模式分解(EMD)包。它的目标是专门为保险和金融风险社区使用,用于诸如回报建模、索赔建模和特别关注死亡率建模的人寿保险应用程序。AdvEMDpy扩展了可用的EMD选项和方法,并提高了它们的统计健壮性和效率,提供了一个健壮、可用和可靠的工具箱。与许多EMD包不同,AdvEMDpy允许用户定制,以确保可以执行更广泛的线性、非线性和非平稳时间序列分析。使用EMD提取的内禀模态函数(IMFs)包含复杂的多频率结构,需要最大限度地定制算法以进行有效分析。该软件包的一个主要贡献是对EMD边缘效应的强化处理,这是EMD和时间序列分析中最普遍存在的问题。在AdvEMDpy中,已经开发、改进并首次编译了各种EMD技术,这些技术的复杂程度各不相同。除了EMD边缘效应之外,AdvEMDpy还整合了许多预处理、后处理、去趋势波动分析(局部趋势估计)技术、停止准则、样条方法、离散时间希尔伯特变换(DTHT)、结点优化和其他算法变化,并向用户展示。本文和补充材料为用户的利益提供了该软件包的几个实际精算应用。
{"title":"Package AdvEMDpy: Algorithmic variations of empirical mode decomposition in Python","authors":"Cole van Jaarsveldt, Matthew Ames, Gareth W. Peters, Mike Chantler","doi":"10.1017/s1748499523000088","DOIUrl":"https://doi.org/10.1017/s1748499523000088","url":null,"abstract":"Abstract This work presents a $textsf{Python}$ EMD package named AdvEMDpy that is both more flexible and generalises existing empirical mode decomposition (EMD) packages in $textsf{Python}$ , $textsf{R}$ , and $textsf{MATLAB}$ . It is aimed specifically for use by the insurance and financial risk communities, for applications such as return modelling, claims modelling, and life insurance applications with a particular focus on mortality modelling. AdvEMDpy both expands upon the EMD options and methods available, and improves their statistical robustness and efficiency, providing a robust, usable, and reliable toolbox. Unlike many EMD packages, AdvEMDpy allows customisation by the user, to ensure that a broader class of linear, non-linear, and non-stationary time series analyses can be performed. The intrinsic mode functions (IMFs) extracted using EMD contain complex multi-frequency structures which warrant maximum algorithmic customisation for effective analysis. A major contribution of this package is the intensive treatment of the EMD edge effect which is the most ubiquitous problem in EMD and time series analysis. Various EMD techniques, of varying intricacy from numerous works, have been developed, refined, and, for the first time, compiled in AdvEMDpy . In addition to the EMD edge effect, numerous pre-processing, post-processing, detrended fluctuation analysis (localised trend estimation) techniques, stopping criteria, spline methods, discrete-time Hilbert transforms (DTHT), knot point optimisations, and other algorithmic variations have been incorporated and presented to the users of AdvEMDpy . This paper and the supplementary materials provide several real-world actuarial applications of this package for the user’s benefit.","PeriodicalId":44135,"journal":{"name":"Annals of Actuarial Science","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136011890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
期刊
Annals of Actuarial Science
全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:604180095
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1