Saddlepoint approximations to the mean and variance of the extended hypergeometric distribution

Conditional inference on 2 x 2 tables with fixed margins and unequal probabilities is based on the extended hypergeometric distribution. If the support of the distribution is large, exact calculation of the conditional mean and variance of the table entry may be computationally demanding. This paper proposes a single‐saddlepoint approximation to the mean and variance. While the approximation achieves acceptable accuracy for ordinary practical purposes, an alternative saddlepoint approximation is provided that gives much closer to exact results. It improves the accuracy of current approximations to up to more than four powers of ten.     

Developing a process for the relative valuation of R&D programmes

This paper addresses the issue of R&D programme prioritisation within a manufacturing company in the aerospace industry, in the context of an overall framework for technology management. A review of approaches to R&D project selection leads into a recent case, which describes how the company developed a practical methodology. The benefits of the process and the relevance of the academic contribution are discussed, leading to a practical checklist for in-company development of a prioritisation process.     

Social capital and soil conservation: evidence from the Philippines*

The formation of social capital is hypothesised to enhance collective efforts for soil conservation. The Landcare Program in the southern Philippines promotes simple conservation practices in upland environments by supporting community landcare groups and municipal landcare associations, thus augmenting social capital. A study was conducted in 2002–2003 to evaluate the Landcare Program, using a mix of quantitative and qualitative techniques. In the present paper, the relationship between social capital formation and adoption of soil conservation in the Municipality of Lantapan is investigated. It is concluded that the Landcare Program as a whole created a valuable stock of bridging social capital, rapidly accelerating the adoption of contour farming measures, but that on‐going support is needed to maintain this capital stock.     

Targeting Monitoring Resources to Enhance the Effectiveness of the CAP

From its inception the operation of the CAP has required the compliance monitoring of farming activities and anticipated increases in the complexity of the monitoring tasks with the introduction of the SFP will stretch monitoring resources even further. We outline the scope for using targeting to enhance effectiveness of monitoring resources in dealing with non-compliant behaviour. Targeting resources can increase information on particular groups making identification of inappropriate behaviour easier. However, in reallocating monitoring resources towards the targeted sub-group, there is likely to be an associated reduction in resources allocated to monitoring non-targeted agents and therefore an increase in their incentive to cheat. To reduce this problem we suggest balancing the targeting-induced reduction in the probability of being caught cheating for non-targeted agents with an appropriate increase in the penalty for those agents if they are caught cheating. This increase in penalty results in an increased divergence between the outcomes from being caught or not caught cheating for non-targeted agents, which increases the overall perceived risk of the cheating option. And for risk-averse agents, this increase is a disincentive to cheating. On this basis we argue for greater use of target-based compliance monitoring as part of the revised and evolving CAP.     

Falling through the cracks: International accounting rate reform at the ITU and WTO

Heightened attention to international accounting rates at the ITU and the WTO has led some observers to conclude that carriers soon will impose cost-based termination charges. This article concludes that while accounting rates have declined on some routes, many incumbent carriers can and will delay or thwart progress. The article examines the FCC's unilateral regulatory initiative as evidence of a growing schism between governments keen on immediate progress and those that fear a ‘free fall’ in accounting rates and a quick end to settlement surpluses. The article also considers technological innovations like call-back and Internet telephony with an eye toward assesssing whether and how widespread accounting rate reductions will occur.     

Seasonal variability,land values and willingness–to–pay for a forward wheat contract with protein premiums and discounts

This article investigates the impact of a protein premiums and discounts system on the income stream from growing wheat. Based on a biological relationship between protein and yield in uncertain seasonal conditions, it shows that such a system reduces the expected level and variability of wheat income. It is subsequently argued, using a numerical analysis, that protein payments affect both the attraction to wheat growers of forward contracts and the value of land used for wheat. The nature of both of these impacts is related to the level of seasonal variability affecting the land. Consequently, wheat growers in the more unreliable regions of the wheatbelt may have been particularly disadvantaged by the system.     

“Panelizing” Repeated Cross Sections

This paper considers the implementation of a non-stationary, heterogeneous Markov model for the analysis of binary dependent variables in a time series of repeated cross-sectional (RCS) surveys. The model offers the opportunity to estimate entry and exit transition probabilities and to examine the effects of time-constant and time-varying covariates on the hazards. We show how maximum likelihood estimates of the parameters can be obtained by Fishers method-of-scoring and how to estimate both fixed and time-varying covariate effects. The model is exemplified with an analysis of the labor force participation decision of Dutch and West German women using ISSP (and other) data from 10 annual Dutch surveys conducted between 1987 and 1996 and 7 annual West German surveys conducted between 1988 and 1994. Some open problems concerning the application of the model are discussed.