Confidence sets for the date of a single break in linear time series regressions

This paper considers the problem of constructing confidence sets for the date of a single break in a linear time series regression. We establish analytically and by small sample simulation that the current standard method in econometrics for constructing such confidence intervals has a coverage rate far below nominal levels when breaks are of moderate magnitude. Given that breaks of moderate magnitude are a theoretically and empirically relevant phenomenon, we proceed to develop an appropriate alternative. We suggest constructing confidence sets by inverting a sequence of tests. Each of the tests maintains a specific break date under the null hypothesis, and rejects when a break occurs elsewhere. By inverting a certain variant of a locally best invariant test, we ensure that the asymptotic critical value does not depend on the maintained break date. A valid confidence set can hence be obtained by assessing which of the sequence of test statistics exceeds a single number.     

Risk measures for derivatives with Markov-modulated pure jump processes

We consider a regime-switching HJB approach to evaluate risk measures for derivative securities when the price process of the underlying risky asset is governed by the exponential of a pure jump process with drift and a Markov switching compensator. The pure jump process is flexible enough to incorporate both the infinite, (small), jump activity and the finite, (large), jump activity. The drift and the compensator of the pure jump process switch over time according to the state of a continuous-time hidden Markov chain representing the state of an economy. The market described by our model is incomplete. Hence, there is more than one pricing kernel and there is no perfect hedging strategy for a derivative security. We derive the regime-switching HJB equations for coherent risk measures for the unhedged position of derivative securities, including standard European options and barrier options. For measuring risk inherent in the unhedged option position, we first need to mark the position into the market by valuing the option. We employ a well-known tool in actuarial science, namely, the Esscher transform to select a pricing kernel for valuation of an option and to generate a family of real-world probabilities for risk measurement. We also derive the regime-switching HJB-variational inequalities for coherent risk measures for American-style options.     

A Discrete Time Equivalent Martingale Measure

An equivalent martingale measure selection strategy for discrete time, continuous state, asset price evolution models is proposed. The minimal martingale law is shown to generally fail to produce a probability law in this context. The proposed strategy, termed the extended Girsanov principle, performs a multiplicative decomposition of asset price movements into a predictable and martingale component with the measure change identifying the discounted asset price process to the martingale component. However, unlike the minimal martingale law, the resulting martingale law of the extended Girsanov principle leads to weak form efficient price processes. It is shown that the proposed measure change is relevant for economies in which investors adopt hedging strategies that minimize the variance of a risk adjusted discounted cost of hedging that uses risk adjusted asset prices in calculating hedging returns. Risk adjusted prices deflate asset prices by the asset's excess return. The explicit form of the change of measure density leads to tractable econometric strategies for testing the validity of the extended Girsanov principle. A number of interesting applications of the extended Girsanov principle are also developed.     

CORPORATE GOVERNANCE IN JAPAN AND THE UK: CODES,THEORY AND PRACTICE

We reflect on the evolution of corporate governance and the role of institutional investors in enhancing governance in Japan and the UK. Japan places emphasis on stakeholder capitalism, whereas the UK places emphasis on shareholder capitalism. Nonetheless, in both countries, institutional investors have exerted significant influence on the evolution of corporate governance. Institutional investors in the UK have more power over company management than their Japanese counterparts, although it is alleged that these powers are not exercised to their best potential in either country.     

Static and dynamic measurement of intra-industry trade and adjustment: A geometric reappraisal

Static and Dynamic Measurement of Intra-Industry Trade and Adjustment: A Geometric Reappraisal. — The principal analytical device used is an industry “trade box” that allows the authors to geometrically examine changes in intra-industry trade (ITT), total trade (TT), net trade (NT) and the Grubel and Lloyd (GL) index as a result of movements in trade points. The authors propose an approach to measure changes in both the absolute and relative valuesof ITTand NT with respect to changes inTT. Their methodology highlights a number of weaknesses with the existing literature on marginalIIT and provides a methodology that can be applied to investigate adjustment implications of changing patterns and levels of intra-industry trade.     

Estimation and Testing of Forecast Rationality under Flexible Loss

In situations where a sequence of forecasts is observed, a common strategy is to examine „rationality” conditional on a given loss function. We examine this from a different perspective—supposing that we have a family of loss functions indexed by unknown shape parameters, then given the forecasts can we back out the loss function parameters consistent with the forecasts being rational even when we do not observe the underlying forecasting model? We establish identification of the parameters of a general class of loss functions that nest popular loss functions as special cases and provide estimation methods and asymptotic distributional results for these parameters. This allows us to construct new tests of forecast rationality that allow for asymmetric loss. The methods are applied in an empirical analysis of IMF and OECD forecasts of budget deficits for the G7 countries. We find that allowing for asymmetric loss can significantly change the outcome of empirical tests of forecast rationality.     

THE ECONOMIC CONSEQUENCES OF HARVESTER

A century has elapsed since the ‘New Protection’ policy of the newly established Commonwealth government of Australia gave birth to the ‘basic wage’ principle following the ‘Harvester’ judgement. This paper re‐examines, with special reference to economic considerations – unemployment, the tariff, and the wage structure – the controversy surrounding the initial formulation of this principle and the evolution of its application under the federal wage fixing tribunals and the legislation under which they operated. It concludes that even the vestigial remains of the concept underlying Harvester have progressively disappeared from Australian wage fixing principles.     

Competition,Cooperation and Regulatory Intervention Impacts on Independent School Fees

This paper examines the factors determining fee levels set by independent schools, focusing on the impact of competition, cooperation and regulatory intervention in the sector. Results indicate that, once account is taken of factors such as the extent of local competition between independent schools, the impact of the 2003–2005 Office of Fair Trading investigation into the fee-setting cartel on independent school fees becomes insignificant. Meanwhile, the extent of competition between independent schools has a significant effect on levels of boarding school fees. Results highlight the importance of considering pricing strategies of groups within a cartel.     

Forecast combination when outcomes are difficult to predict

We show that when outcomes are difficult to forecast in the sense that forecast errors have a large common component that (a) optimal weights are not affected by this common component, and may well be far from equal to each other but (b) the relative mean square error loss from averaging over optimal combination can be small. Hence, researchers could well estimate combining weights that indicate that correlations could be exploited for better forecasts only to find that the difference in terms of loss is negligible. The results then provide an additional explanation for the commonly encountered practical situation of the averaging of forecasts being difficult to improve upon.     

Hospital staff shortage: the role of the competitiveness of pay of different groups of nursing staff on staff shortage

Shortages of nursing staff in OECD countries have been a preoccupation for policy makers. Shortages of staff may be the consequence of uncompetitive pay. In the private sector, employers in different regions can offer different pay rates to reflect local amenities and cost of living. Hospitals in the UK however cannot set the pay for their employees, and as a result they might therefore incur staff shortages. Moreover, occupational groups do not operate in isolation. Shortages of staff may also be the consequence of the competitiveness of pay of an alternative group of staff. This is investigated using two distinct groups of nursing staff: assistant nurses (ANs) and registered nurses (RNs) working in English hospitals in 2003–2005 using national-level data sets. We find that an increase by 10% of the pay competitiveness of RNs decreases the shortage of both the RNs and of ANs by 0.6% and 0.4%, respectively.