Repeated audit controls

An important task of auditors is to check whether recorded values are correct. From the number (or total) of the errors found in a sample, upper confidence limits for the fraction (or total) of the errors in the population are calculated by standard methods.
Even auditors are human, however, and may make mistakes: errors may remain unnoticed. As administrative rules and regulations are becoming more and more complicated, this kind of auditors' mistakes tends to occur more frequently. Hence, there is an increasing need to check the auditing process itself. This can be achieved by checking a subsample of audited values a second time, now by an error-free supervisor.
This paper investigates the consequences of the (possible) occurrence of errors in this subsample. A simple and analytically attractive model is presented for the number of errors found in this double inspection scheme. Maximum likelihood estimators are derived for the population fraction of errors and the probability of an error remaining unnoticed. Based on that, an exact upper confidence limit for the population fraction of errors is calculated, treating the probability of an unnoticed error as a nuisance parameter. Our method was originally developed during a recent Dutch case study: in a subsample of already audited values one additional error was found by the supervisor. It is shown that, as a consequence, the upper confidence limit is increased very sizeably.     

Predicting early adoption of successive video player generations

Early adopters play an important role in the innovation diffusion process. Over the past decades, many factors have been identified as predictors for early adoption of innovations. Less attention has been paid to the relationship between the early adoption of one generation of a specific product and the early adoption of successive product generations. This paper analyzes how early adoption of a new product generation depends on ownership, purchase experience and adoption times for previous generations of the same product. The paper develops predictive models of early adoption for four generations of video player products, based on a survey among 815 Australian consumers. The model allows the testing of various hypotheses. It is shown that previous generation variables outperform conventional socio-demographic and psychographic variables in predicting early adoption but also that the two variable types complement each other. The best predicting models include both previous generation and socio/psychographic variables. It is concluded that previous generation models have substantial merits for new product forecasting as they are more parsimonious than conventional models and the data required to estimate them is relatively easy to obtain.     

Random incentive systems in a dynamic choice experiment

Experiments frequently use a random incentive system (RIS), where only tasks that are randomly selected at the end of the experiment are for real. The most common type pays every subject one out of her multiple tasks (within-subjects randomization). Recently, another type has become popular, where a subset of subjects is randomly selected, and only these subjects receive one real payment (between-subjects randomization). In earlier tests with simple, static tasks, RISs performed well. The present study investigates RISs in a more complex, dynamic choice experiment. We find that between-subjects randomization reduces risk aversion. While within-subjects randomization delivers unbiased measurements of risk aversion, it does not eliminate carry-over effects from previous tasks. Both types generate an increase in subjects’ error rates. These results suggest that caution is warranted when applying RISs to more complex and dynamic tasks.     

Simon Kuipers: An Economist in Search of Rigour and Relevance

At the end of 1997 and after twenty-five years of duty, Professor Simon Kuipers retired as managing editor of De Economist. As a token of indebtedness and gratitude, this article reviews Kuipers' written work. The article focuses on two topics that dominate Kuipers' endeavours. First, his contributions to macroeconomic theory, with particular emphasis on his (neo-)Keynesian approach are examined. Second, Kuipers' contributions to actual monetary and economic policy are discussed, emphasis being placed on his empirical work.     

A new risk-based design approach for hydraulic engineering

Hydraulic structures providing flood and coastal protection facilitate economic development as well as living areas and often converge with other infrastructure. There is a need for general guidance for analysing risks of hydraulic structures. This paper analyses two actual hydraulic engineering projects in the UK in which acceptable risk levels are incorporated in the design using a new risk-based design approach, taking consciously into account the influence of stakeholders, the legal framework as set by the Government, design-elements from different design-disciplines and funding.     

Recreational demand for farm commonage in Ireland: A contingent valuation assessment

This paper measures willingness to pay (WTP) for public access and trail improvements on commonage farmland for recreational walking in upland and lowland areas of Connemara region in the West of Ireland using the contingent valuation method (CVM). Common to both upland and lowland commonage sites was the much higher ranking for infrastructural features by those WTP for scenario implementation compared to those preferring the status quo. Results for those expressing a positive WTP reveal a median willingness to pay (MWTP) for formal access with improved trail infrastructure of €12.22 for the lowlands compared with €9.08 for the uplands.     

Monitoring in service triads consisting of buyers, subcontractors and end customers

Organisations increasingly outsource service delivery to specialist subcontractors. These buyers, their subcontractors and their end customers operate in a triadic service relationship. In these triads, the buyer lacks direct control over service delivery and completely depends on the subcontractor for its performance towards its end customers. Subcontractors are confronted with two principals (buyer and end customer) who may have conflicting objectives.Although traditionally focusing on dyadic buyer–seller relationships rather than triads, Agency Theory provides valuable suggestions on the type of contract to be used and the type of monitoring to be employed. We adopt Agency Theory as a theoretical lens to look at the buyer–subcontractor–end customer triad and develop propositions on the design of contractual arrangements and monitoring activities. We use the results of two cases of service triads to provide some initial validation for these propositions.