Multivariate Insurance Loss Models with Applications in Risk Retention

Multivariate Insurance Loss Models with Applications in Risk Retention

Author: Gee Yul Lee

Publisher:

Published: 2017

Total Pages: 0

ISBN-13:

DOWNLOAD EBOOK

This dissertation contributes to the risk and insurance literature by expanding our understanding of insurance claims modeling, deductible ratemaking, and the insurance risk retention problem. In the claims modeling part, a data-driven approach is taken to analyze insurance losses using statistical methods. It is often common for an analyst to be interested in several outcome measures depending on a large set of explanatory variables, with the goal of understanding both the average behavior, and the overall distribution of the outcomes. The use of multivariate analysis has an advantage in a broad context, and the literature on multivariate regression modeling is extended with a focus on dependence among multiple insurance lines. In this process, a deductible is an important feature of an insurance policy to consider, because it may influence the frequency and severity of claims to be censored or truncated. Standard textbooks have approached deductible ratemaking using models for coverage modification, utilizing parametric loss distributions. In practice, regression could be used with explanatory variables including the deductible amount. The various approaches to deductible ratemaking are compared in this dissertation. Ultimately, an insurance manager would be interested in understanding the influence of a retention parameter change to the risk of a portfolio of losses. The retention parameter may be deductible, upper limit, or coinsurance. This dissertation contributes to the statistics and actuarial literature by introducing and applying the 01-inflated negative binomial frequency model (a frequency model for observations with an inflated number of zeros and ones), and illustrating how discrete and continuous copula methods can be empirically applied to insurance claims analysis. In the process, the dissertation provides a comparison among various deductible analysis procedures, and shows that the regression approach has an advantage in problems of moderate size. Finally, the dissertation attempts to broaden our understanding of the risk retention problem within a constrained optimization framework, and demonstrates the quasiconvexity of the objective function in this problem. The dissertation reveals that the loading factor of a reinsurance premium has a risk measure interpretation, and relates to the risk measure relative margins (RMRM). Concepts are illustrated using the Wisconsin Local Government Property Insurance Fund (LGPIF) data.


A Multivariate Claim Count Model for Applications in Insurance

A Multivariate Claim Count Model for Applications in Insurance

Author: Daniela Anna Selch

Publisher: Springer

Published: 2018-08-31

Total Pages: 167

ISBN-13: 3319928686

DOWNLOAD EBOOK

This monograph presents a time-dynamic model for multivariate claim counts in actuarial applications. Inspired by real-world claim arrivals, the model balances interesting stylized facts (such as dependence across the components, over-dispersion and the clustering of claims) with a high level of mathematical tractability (including estimation, sampling and convergence results for large portfolios) and can thus be applied in various contexts (such as risk management and pricing of (re-)insurance contracts). The authors provide a detailed analysis of the proposed probabilistic model, discussing its relation to the existing literature, its statistical properties, different estimation strategies as well as possible applications and extensions. Actuaries and researchers working in risk management and premium pricing will find this book particularly interesting. Graduate-level probability theory, stochastic analysis and statistics are required.


Copula-Based Multivariate Models with Applications to Risk Management and Insurance

Copula-Based Multivariate Models with Applications to Risk Management and Insurance

Author: Marco Bee

Publisher:

Published: 2005

Total Pages: 27

ISBN-13:

DOWNLOAD EBOOK

The purpose of this paper consists in analysing the relevance of dependence concepts in finance, insurance and risk management, exploring how these concepts can be implemented in a statistical model via copula functions and pointing out some difficulties related to this methodology. In particular, we first review the statistical models currently used in the actuarial and financial fields when dealing with loss data; then we show, by means of two risk management applications, that copula-based models are very flexible but sometimes difficult to set up and to estimate; finally we study, by means of a simulation experiment, the properties of the maximum likelihood estimators of the Gaussian and Gumbel copula.


Risk Models Defined With Multivariate Mixtures of Exponential Distributions

Risk Models Defined With Multivariate Mixtures of Exponential Distributions

Author: Hélène Cossette

Publisher:

Published: 2019

Total Pages: 30

ISBN-13:

DOWNLOAD EBOOK

Mixed exponential distributions are frequently used in actuarial risk modeling. Distributions obtained through mixtures allow greater flexibility in the modeling of non-life insurance loss amounts . Several research works have studied mixed exponential distributions in univariate and multivariate settings. The present paper highlights the usefulness of such distributions and lays the story of the mixing technique behind them. It also explains the underlying link between all these works. In addition, a comprehensive study of three special cases of mixing distributions is considered. Applications in actuarial science of these distributions are presented throughout the paper highlighting their many uses and useful properties.


Insurance Applications of Some New Dependence Models Derived from Multivariate Collective Models

Insurance Applications of Some New Dependence Models Derived from Multivariate Collective Models

Author: Enkelejd Hashorva

Publisher:

Published: 2017

Total Pages: 21

ISBN-13:

DOWNLOAD EBOOK

Consider two different portfolios which have claims triggered by the same events. Their corresponding collective model over a fixed time period is given in terms of individual claim sizes $(X_i,Y_i), i ge 1$ and a claim counting random variable $N$. In this paper we are concerned with the joint distribution function $F$ of the largest claim sizes $(X_{N:N}, Y_{N:N})$. By allowing $N$ to depend on some parameter, say $ theta$, then $F=F( theta)$ is for various choices of $N$ a tractable parametric family of bivariate distribution functions. We present three applications of the implied parametric models to some data from the literature and a new data set from a Swiss insurance company. Furthermore, we investigate both distributional and asymptotic properties of $(X_{N:N,Y_{N:N})$


Applications of Pascal Mixture Models to Insurance and Risk Management

Applications of Pascal Mixture Models to Insurance and Risk Management

Author: Dameng Tang

Publisher:

Published: 2016

Total Pages:

ISBN-13:

DOWNLOAD EBOOK

This thesis studies the applications of Pascal mixture models in three closely related topics in insurance and risk management. The first topic is on the modeling of correlated frequencies of operational risk (OR) losses from financial institutions. We propose a copula-free approach for modeling correlated frequencies using an Erlang-based multivariate mixed Poisson distribution. Many properties possessed by this class of distributions are investigated and a tailor-made generalized expectation-maximization (EM) algorithm is derived for fitting purposes. The applicability of the proposed distribution is illustrated in an OR management context, where this class is used to model the OR loss. The accuracy of the proposed approach is analyzed using a modified real operational loss data set. The second topic is about multivariate count regression with application in modeling correlated claim frequencies. We propose a multivariate Pascal mixture regression model as an alternative to understand the association between multivariate count response variables and their covariates. We examine the many properties possessed by this class of regression. A generalized EM algorithm is derived for fitting purposes, which also provides the standard errors of the regression coefficients which are useful for inference. Its applicability is demonstrated by fitting an automobile insurance claim count data set. The third topic is about modeling and predicting the number of incurred but not reported (IBNR) claims in Property Casualty (P) insurance. We model the claim arrival process together with the reporting delays as a marked Cox process whose intensity function is governed by a hidden Markov chain. The associated reported claim process and IBNR claim process remain to be marked Cox processes with easily convertible intensity functions and marking distributions. Closed-form expressions for both the autocorrelation function (ACF) and the distributions of the numbers of reported claims and IBNR claims are derived. A generalized EM algorithm is obtained to estimate the model parameters. The proposed model is examined through simulation studies and is also applied to a real insurance claim data set. We compare the predictive distributions of our model with those of the over-dispersed Poisson model (ODP), a stochastic model that underpins the widely used chain-ladder method.


Modeling Dependence Induced by a Common Random Effect and Risk Measures with Insurance Applications

Modeling Dependence Induced by a Common Random Effect and Risk Measures with Insurance Applications

Author: Junjie Liu

Publisher:

Published: 2012

Total Pages: 0

ISBN-13:

DOWNLOAD EBOOK

Random effects models are of particular importance in modeling heterogeneity. A commonly used random effects model for multivariate survival analysis is the frailty model. In this thesis, a special frailty model with an Archimedean dependence structure is used to model dependent risks. This modeling approach allows the construction of multivariate distributions through a copula with univariate marginal distributions as parameters. Copulas are constructed by modeling distribution functions and survival functions, respectively. Measures of the dependence are applied for the copula model selections. Tail-based risk measures for the functions of two dependent variables are investigated for particular interest. The statistical application of the copula modeling approach to an insurance data set is discussed where losses and loss adjustment expenses data are used. Insurance applications based on the fitted model are illustrated.


Risk Modelling in General Insurance

Risk Modelling in General Insurance

Author: Roger J. Gray

Publisher: Cambridge University Press

Published: 2012-06-28

Total Pages: 409

ISBN-13: 0521863945

DOWNLOAD EBOOK

A wide range of topics give students a firm foundation in statistical and actuarial concepts and their applications.