A note on different models of stochastic processes dealt with in the collective theory of risk

Abstract

1. For the definition of general processes with special regard to those concerned in Collective Risk Theory reference is made to Cramér (Collective Risk Theory, Skandia Jubilee Volume, Stockholm, 1955). Let the independent parameter of such a process be denoted by τ, with the origin at the point of departure of the process and on a scale independent of the number of expected changes of the random function. Denote with p(τ, n)dt the asymptotic expression for the conditional probability of one change in the random function while the parameter passes from τ to τ + dτ: relative to the hypothesis that n changes have occurred, while the parameter passes from 0 to τ. Assume further—unless the contrary is stated—that the probability of more than one change, while the parameter passes from τ to τ + dτ, is of smaller order than dτ.     

Lewis' branching poisson process model from the point of view of the theory of compound poisson processes

Abstract

1. Lewis [1] has used a composite process as a model for computer failure patterns. This model seems to be of a much wider scope of application at least after some modifications, which are discussed in this note. ¹ The present author has read Lewis [1] only in the form of a galley proof with due regard to a few corrections kindly communicated by Lewis. This note was prepared in 1964 before the publication of Lewis' paper.      

The Displacement Effect of Public Pensions on the Accumulation of Financial Assets*

The generosity of public pensions may depress private savings and provide incentives to retire early. While there is plenty of evidence supporting the latter effect, there remains considerable controversy over whether public pensions crowd out private savings. This paper uses international micro‐data sets collected over recent years to investigate whether public pensions displace private savings. The identification strategy relies not only on cross‐country differences in generosity but also on differences in the progressivity or non‐linearity of pension formulas across countries. We estimate that an extra dollar of pension wealth depresses accumulated financial assets around the time of retirement by 22 cents. An extra 10,000 dollars in public pension wealth reduces the average retirement age by roughly one month, which implies an elasticity of years of retirement with respect to pension wealth of 0.15.     

Benchmarking Risk Management Within the International Water Utility Sector. Part I: Design of a Capability Maturity Methodology

Risk management in the water utility sector is becoming increasingly explicit. However, due to the novelty and complexity of the discipline, utilities are encountering difficulties in defining and institutionalising their risk management processes. In response, the authors have developed a sector specific capability maturity methodology for benchmarking and improving risk management. The research, conducted in consultation with water utility practitioners, has distilled risk management into a coherent, process‐based framework. We identified eleven risk management processes, and eight key attributes with characterise the extent to which these processes are defined, controlled and institutionalised. Implementation of the model should enable utilities to more effectively employ their portfolio of risk analysis techniques for optimal, credible and defensible decision making.     

A behavioural model of investor sentiment in limit order markets

By incorporating behavioural sentiment in a model of a limit order market, we show that behavioural sentiment not only helps to replicate most of the stylized facts in limit order markets simultaneously, but it also plays a unique role in explaining those stylized facts that cannot be explained by noise trading, such as fat tails in the return distribution, long memory in the trading volume, an increasing and non-linear relationship between trade imbalance and mid-price returns, as well as the diagonal effect, or event clustering, in order submission types. The results show that behavioural sentiment is an important driving force behind many of the well-documented stylized facts in limit order markets.     

Are fully independent audit committees really necessary?

Accounting scandals and concerns about the quality of financial statements have led to many calls for improved audit committee effectiveness. Prior research indicates that audit committee independence is positively related to effective oversight of the financial reporting process. Unfortunately, prior research has not provided an answer as to how much independence on the audit committee is enough. This is an important unanswered question because while Section 301 of the Sarbanes-Oxley Act of 2002 (SOX) currently requires all listed companies to maintain an audit committee that is 100% independent there has been much debate regarding easing the SOX requirements for smaller and foreign companies. In this paper we examine whether the regulatory requirements of a completely independent audit committee are necessary to obtain the monitoring benefits related to audit committee independence that have been documented in prior literature. Our results suggest that the benefits of audit committee independence are consistently achieved only when the audit committee is completely independent. These results provide support for the SOX requirement of 100% independent audit committees.     

Using Market Structure to Regulate a Vertically Integrated Monopolist

A natural monopolist whose cost is private information produces a good which is combined with another good that can be produced by the monopolist or by other firms. The agency that regulates the monopolist can impose any of several different market structures in the industry: integrated monopoly, vertical separation with free entry downstream, or liberalization downstream (both integrated and independent production). When several firms produce downstream, a Cournot quantity-setting game with free entry determines the market price. We derive the optimal contracts to offer the monopolist under all three market structures and examine the influence of downstream cost differences on access prices.We then study the optimal regulatory policy where the regulator can condition the downstream market structure on the monopolist's cost report to the regulator. The optimal regulatory policy awards a monopoly to a low-cost upstream firm, but requires free entry downstream if the monopolist reports high upstream costs. Thus, the choice of market structure is an additional tool to limit rent extraction by the monopolist. Simulation analysis reveals the possibility of significant welfare gains from this additional regulatory tool.