Customer loyalty is crucial for internet services since retaining users of a service to ensure the staying time of the service is of signi€cance for increasing revenue. It demands the retention of customers to be high enough to meet the needs for yielding pro€t for the internet servers. Besides, the growing of rich purchasing interaction feedback helps in uncovering the inner mechanism of purch...

We study the moral hazard problem without the first-order approach or other common structure. We present sufficient conditions under which the shadow value of simultaneously tightening the minimum payment and individual rationality constraints has a simple and intuitive expression. We then show how this expression can be used to perform comparative statics exercises in which we study (i) the ef...

The convergence of the Internet, electronic commerce, and wireless technology has created the basis for the rapid global diffusion of mobile commerce. We believe that one approach to understand mobile commerce diffusion is to study the diffusion of digital mobile devices required in m-commerce activities. Although prior research in technology diffusion has identified a set of variables that aff...

A new approach to moral hazard is presented. Once local incentive compatibility is satisfied, the problem of verifying global incentive compatibility is shown to be isomorphic to the problem of comparing two classes of distribution functions. Thus, tools from choice under uncertainty can be brought to bear on the problem. The approach allows classic justifications of the first-order approach (F...

background: the aim of this study was to detect prognostic factors in recurrent breast cancer metastasis. materials and methods: th is retrospective cohort study employed data from 996 breast cancer patients of isfahan seyed-o-shohada research center from 1998 to 2010. stratifi ed cox proportional hazards model, marginal approach, was used to evaluate the prognostic value of estrogen receptor, ...

BACKGROUND AND AIMS Large metropolitan areas often exhibit multiple morbidity hotspots. However, the identification of specific health hazards, associated with the observed morbidity patterns, is not always straightforward. In this study, we suggest an empirical approach to the identification of specific health hazards, which have the highest probability of association with the observed morbidi...

The threat of impact on Earth of an asteroid or comet, while of very low probability, has the potential to create public panic and – should an impact happen – be sufficiently destructive (perhaps on a global scale) that an integrated approach to the science, technology, and public policy aspects of the impact hazard is warranted. This report outlines the breadth of the issues that need to be ad...

Hazards act upon vulnerability and exposure to create disaster risk. Despite the growth of risk assessments, number approaches that develop studies is still small when compared with hazard modelling. In fact, limited have considered relationship between variables how this can change future management actions on a local scale. This paper addresses gap by proposing an integrated framework combina...