852 research outputs found

    An Empirical Analysis of Dynamic Multiscale Hedging using Wavelet Decomposition

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    This paper investigates the hedging effectiveness of a dynamic moving window OLS hedging model, formed using wavelet decomposed time-series. The wavelet transform is applied to calculate the appropriate dynamic minimum-variance hedge ratio for various hedging horizons for a number of assets. The effectiveness of the dynamic multiscale hedging strategy is then tested, both in- and out-of-sample, using standard variance reduction and expanded to include a downside risk metric, the time horizon dependent Value-at-Risk. Measured using variance reduction, the effectiveness converges to one at longer scales, while a measure of VaR reduction indicates a portion of residual risk remains at all scales. Analysis of the hedge portfolio distributions indicate that this unhedged tail risk is related to excess portfolio kurtosis found at all scales.

    Logic Programming: Context, Character and Development

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    Logic programming has been attracting increasing interest in recent years. Its first realisation in the form of PROLOG demonstrated concretely that Kowalski's view of computation as controlled deduction could be implemented with tolerable efficiency, even on existing computer architectures. Since that time logic programming research has intensified. The majority of computing professionals have remained unaware of the developments, however, and for some the announcement that PROLOG had been selected as the core language for the Japanese 'Fifth Generation' project came as a total surprise. This thesis aims to describe the context, character and development of logic programming. It explains why a radical departure from existing software practices needs to be seriously discussed; it identifies the characteristic features of logic programming, and the practical realisation of these features in current logic programming systems; and it outlines the programming methodology which is proposed for logic programming. The problems and limitations of existing logic programming systems are described and some proposals for development are discussed. The thesis is in three parts. Part One traces the development of programming since the early days of computing. It shows how the problems of software complexity which were addressed by the 'structured programming' school have not been overcome: the software crisis remains severe and seems to require fundamental changes in software practice for its solution. Part Two describes the foundations of logic programming in the procedural interpretation of Horn clauses. Fundamental to logic programming is shown to be the separation of the logic of an algorithm from its control. At present, however, both the logic and the control aspects of logic programming present problems; the first in terms of the extent of the language which is used, and the second in terms of the control strategy which should be applied in order to produce solutions. These problems are described and various proposals, including some which have been incorporated into implemented systems, are described. Part Three discusses the software development methodology which is proposed for logic programming. Some of the experience of practical applications is related. Logic programming is considered in the aspects of its potential for parallel execution and in its relationship to functional programming, and some possible criticisms of the problem-solving potential of logic are described. The conclusion is that although logic programming inevitably has some problems which are yet to be solved, it seems to offer answers to several issues which are at the heart of the software crisis. The potential contribution of logic programming towards the development of software should be substantial

    Scaling the twin peaks : systemic risk and dual regulation

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    In April 2013, the UK implemented a dual-regulation approach to financial services often referred to as twin peaks. In this paper, we assess the impact of the introduction of twin peaks regulation on the systemic risk contributions of UK financial institutions. Using a matched sample of single- and dual-regulated financial institutions, we provide evidence that twin peaks regulation resulted in a relative reduction in systemic risk for dual-regulated firms

    A4_16 Set Phasers to stun

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    This article considers the possibility of creating a ’stun ray’ style weapon similar in concept to the phaserused in Star Trek when on a setting to stun its target. It is found that in order to create such an energybased stun weapon which was effective over a similar range to that of the phaser which did not simplykill the target should be technologically possible

    A4_9 Water-Propelled Jetpacks

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    Theoretically it would be possible to create a jetpack that used water as a primary propulsion method. This paper looks at the physics behind such a proposition, by deriving a relationship between the mass of the water required m and the time spent airborne t. The masses of water involved are analysed for practicability, and it is found that 99.0 kg of water is required per second of flight, which is concluded to be an unfeasibly large amount

    A4_8 Don't Aim at Him!

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     This paper investigates the horizontal deviation due to gravity that would be experienced by a bullet fired from a rifle. The paper looks at the recent setting of a new sharpshooting distance record as a case study for the investigation. While the deviation quoted by the soldier involved significantly differed from that calculated we show that a significant deviation is measured
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