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To provide a brief introduction to warranty analysis and a classification of general repairs. To introduce the notion of accelerated probability distribution and use it to model imperfect warranty repairs.

The notion of accelerated probability distribution is discussed and its similarity with quasi‐renewal and geometric processes is observed. An approach to modeling imperfect warranty repairs based on the accelerated probability distributions is presented, and the corresponding expected warranty cost over the warranty period under non‐renewing free replacement warranty policy is evaluated.

It is observed that quasi‐renewal and the geometric processes are equivalent. Using data from an existing warranty database it is shown that the inter‐repair times form a quasi‐renewal process. The corresponding expected warranty cost over the warranty period under a non‐renewing free replacement warranty policy is evaluated.

This approach is applicable only if the cost of the warranty repair is an increasing function of the number of repairs.

Provides a useful approach to modeling inter‐repair times incorporating the idea of imperfect repairs in practice.

Provides an approach to model imperfect warranty repairs and to evaluate the corresponding expected warranty cost.

The purpose of this paper is to review and develop stochastic models for the evaluation of the expected warranty cost, from dealer's viewpoint, for second hand items sold under different warranty policies.

This study makes a useful contribution to the warranty literature by developing a framework to study one dimensional warranty policies for second‐hand products from dealer's viewpoint. Also, numerical examples are provided to illustrate the application of these models.

Despite the fact that warranties for second‐hand products are commonly used, the accurate pricing of warranties in many situations remains an unsolved problem, for both the dealer and customer. The proposed framework allows the dealer to analyze the cost of alternative warranty policies before deciding on the policy to be offered with the sale of a second‐hand item.

The policies and models developed in this paper can be useful in managerial decisions making related to second‐hand products such as automobiles, home appliances, helicopters, electronic equipment and electronics.

To investigate the optimal burn‐in time from the perspective of minimizing the expected total cost (i.e. manufacturing plus warranty costs) per unit of product sold under a failure‐free renewing warranty policy. The conditions indicating when burn‐in becomes beneficial were also derived.

An age‐dependent general repairable product sold under a failure‐free renewing warranty agreement was considered. In the case of such a general repairable model, there are two ways in which the product can fail: type I failure (minor) can be rectified through minimal repairs; while in type II failure (catastrophic), the product must be replaced. Then optimal burn‐in time is then examined in order to achieve a trade‐off between reducing the warranty cost and increasing the manufacturing cost.

The optimal burn‐in time depends on the failure/repair characteristics, length of warranty, cost parameters and the probability of failure type II (catastrophic). A burn‐in program is beneficial if the initial failure rate is high or product failures during the warranty period are costly. Moreover, the optimal burn‐in time is always less than the infant mortality period.

The product considered in this paper is an age‐dependent general repairable product: on which no such study has yet been conducted. This is also the first study to apply a failure‐free renewing warranty to a general repairable item. It can be seen that the present model is a generalization of the model considered by Chien and Sheu.

To provide a brief survey of the literature directed towards the analysis of warranty claim data.

For convenience, this survey of the analysis of warranty claims data is somewhat arbitrarily be classified by topics as follows: age‐based claims analysis, aggregated warranty claims analysis, marginal counts of claims analysis, warranty claims analysis by using covariates, estimation of lifetime distribution using supplementary data, two‐dimensional warranty, warranty costs analysis, sales lag and reporting lag analysis, and forecasts of warranty claims.

Emphasis is placed on a discussion of different kinds of warranty claims data selected from reviews and on a comparison of the statistical models and methods used to analyze such data.

Since the literature on product warranty data is vast, more work on this problem is needed.

This review points out why warranty claims data is important and gives a survey of the literature pertaining to the analysis of such data. The emphasis is on the analysis of minimal databases of real warranty data, constructed by combining information from different sources, which can be collected economically and efficiently through service networks. The research is applicable for those responsible for product reliability, product design decisions and warranty management in manufacturing industries.

The paper reviews different statistical models and methods used to analyze warranty claims data. The statistical models and methods presented are be valuable and meaningful tools for product reliability and warranty management and analysis.

To consider the problem of outsourcing warranty repairs to outside vendors when items have priorities in service.

The repair allocation problem is formulated as a convex minimum‐cost network flow problem and solve it by the successive shortest path algorithm. The computation issues involved with the problem are also discussed.

Examples are provided to illustrate the cost benefits achieved due to the priority structure.

The research uses a closed static allocation model. Future research efforts can expand our model by considering a dynamic allocation method or an open population model.

The paper can be a valuable resource to warranty managers who make decisions regarding the negotiations of warranty contracts and the allocation of items to outside repair vendors.

A warranty manager can apply our results to receive insight on the value of giving priority in service to special customers. In addition, resource allocation problems with an objective structure similar to our application can be efficiently solved using our algorithm.

To make a theoretical comparison between two scale‐inspection and warranty policies for weight‐quality, one practical and the other theoretically grounded.

Comparison is made in a Stackelberg game framework considering the consumer's as well as the manufacturer's viewpoint.

The practical policy is more profitable for the manufacturer than the theoretical policy in many cases.

The study confines itself to scale‐inspection and warranty policies, but the underlying approach used in this paper can also be applied to other topics.

The proposed model can also provide a lower bound for the warranty.

The study compares a practical policy with a theoretical one from both the consumer's and manufacturer's point of view.

To determine the optimal software warranty period in continuous and discrete circumstances where the difference between the software testing environment and the operational environment can be characterised by an environment factor.

Software reliability models based on continuous and discrete time non‐homogeneous Poisson processes are assumed to describe the failure occurrence phenomena under both environments. Based on the idea of accelerated life testing for hardware products, the operational profile of the software is modeled, and the total expected software cost incurred in both testing and operational phases is formulated.

Under a milder condition, the optimal warranty period which minimizes the total software cost is derived analytically.

This paper introduces the operational profile of software to model the difference between the testing environment and the operational environment.