PRE-TEST ESTIMATION AND TESTING IN ECONOMETRICS: RECENT DEVELOPMENTS

Abstract. This paper surveys a range of important developments in the area of preliminary-test inference in the context of econometric modelling. Both pre-test estimation and pre-test testing are discussed. Special attention is given to recent contributions and results. These include analyses of pre-test strategies under model mis-specification and generalised regression errors; exact sampling distribution results; and pre-testing inequality constraints on the model's parameters. In many cases, practical advice is given to assist applied econometricians in appraising the relative merits of pre-testing. It is shown that there are situations where pre-testing can be advantageous in practice     

Party Politics and the Political Economy of Ghana’s Oil

Ghana’s status as a new oil producer raises questions about the developmental effects of resources, and the role of political institutions in these processes. The conundrum this paper addresses is the rather limited impact of oil exploitation in Ghana despite the country’s strong democratic record and internationally acclaimed oil governance legislation. The reasons for this lie in the nature of elite-based political coalitions and we root our analysis of Ghana’s hydrocarbons in the political settlements literature, which moves us beyond the ‘good governance’ approaches so often linked to ‘resource curse’ thinking. We also move beyond the instrumentalism of political settlements theory to examine the role political ideas play in shaping resource governance. We argue that inter-coalitional rivalry has generally undermined the benefits of Ghana’s oil but that a crude interests-based interpretation is insufficient to explain differences between these coalitions.     

The learning path of the hidden economy: the tax burden and tax evasion in New Zealand

This paper considers the ‘learning curve’ relationship between the aggregate tax rate and the relative size of the hidden economy in New Zealand. Some simple non-linear models are estimated so that the effects of changes in the effective tax rate on the underground economy can be simulated. This study finds that about half of the hidden activity in New Zealand is a learned response to changing opportunities and constraints in fiscal policy, but this amount varies over the business cycle. Simulating a zero tax rate permits us to discover the ‘natural rate’ of underground and criminal activity. Some partial lessons are drawn for taxation policy in that country.     

Institutional arrangements of outgrower sugarcane production in Southern Africa

ABSTRACT

Management models are needed that empower local communities to produce biofuel feedstock in a manner that drives rural development. Much can be learnt through the accumulated experiences of sugarcane outgrower schemes in southern Africa. Early schemes provided limited empowerment, but protected outgrowers from the risks of volatile sugar value chains. In later schemes, processing plants were responsible for all operations and simply paid dividends to participating farmers. More recent schemes offer full ownership, which comes with greater rewards and empowerment, but also exposure to risks. The underlying institutional structures of outgrower schemes largely dictate their performance, and thus the factors that affect their viability or collapse. To understand the different institutional arrangements of sugarcane outgrower schemes we undertake a comparative analysis of 13 schemes in southern Africa employing a political economy framework that uses the three key questions: ‘who owns what’, ‘who does what’, and ‘who gets what’.     

Economic Analysis for Ecosystem Service Assessments

The paper seeks to contribute to the expanding literature on ecosystem service assessment by considering its integration with economic analyses of such services. Focussing upon analyses for future orientated policy and decision making, we initially consider a single period during which ecological stocks are maintained at sustainable levels. The flow of ecosystems services and their contribution to welfare bearing goods is considered and methods for valuing resultant benefits are reviewed and illustrated via a case study of land use change. We then broaden our time horizon to discuss the treatment of future costs and benefits. Finally we relax our sustainability assumption and consider economic approaches to the incorporation of depleting ecological assets with a particular focus upon stocks which exhibit thresholds below which restoration is compromised.     

Analysing multi-level Monte Carlo for options with non-globally Lipschitz payoff

Giles (Oper. Res. 56:607–617, 2008) introduced a multi-level Monte Carlo method for approximating the expected value of a function of a stochastic differential equation solution. A key application is to compute the expected payoff of a financial option. This new method improves on the computational complexity of standard Monte Carlo. Giles analysed globally Lipschitz payoffs, but also found good performance in practice for non-globally Lipschitz cases. In this work, we show that the multi-level Monte Carlo method can be rigorously justified for non-globally Lipschitz payoffs. In particular, we consider digital, lookback and barrier options. This requires non-standard strong convergence analysis of the Euler–Maruyama method.