Bending It Like Beckham: How to Visually Fool the Goalkeeper

Background: As bending free-kicks becomes the norm in modern day soccer, implications for goalkeepers have largely been ignored. Although it has been reported that poor sensitivity to visual acceleration makes it harder for expert goalkeepers to perceptually judge where the curved free-kicks will cross the goal line, it is unknown how this affects the goalkeeper's actual movements.

Methodology/Principal Findings: Here, an in-depth analysis of goalkeepers' hand movements in immersive, interactive virtual reality shows that they do not fully account for spin-induced lateral ball acceleration. Hand movements were found to be biased in the direction of initial ball heading, and for curved free-kicks this resulted in biases in a direction opposite to those necessary to save the free-kick. These movement errors result in less time to cover a now greater distance to stop the ball entering the goal. These and other details of the interceptive behaviour are explained using a simple mathematical model which shows how the goalkeeper controls his movements online with respect to the ball's current heading direction. Furthermore our results and model suggest how visual landmarks, such as the goalposts in this instance, may constrain the extent of the movement biases.

Conclusions: While it has previously been shown that humans can internalize the effects of gravitational acceleration, these results show that it is much more difficult for goalkeepers to account for spin-induced visual acceleration, which varies from situation to situation. The limited sensitivity of the human visual system for detecting acceleration, suggests that curved free-kicks are an important goal-scoring opportunity in the game of soccer.

Enforcing Employment Discrimination Law - Potential Transplants from Italy to Britain and Vice Versa?

While substantive EU non-discrimination law has been harmonized in great detail, the enforcement regime for EU non-discrimination law consists merely of a few isolated elements. Thus, the pursuit of unity through harmonization in substantive EU law is accompanied by considerable regulatory autonomy for Member States in securing the efficiency of those laws, reflecting the diversity of national enforcement regimes, and resulting in twenty-seven different national models for enforcing discrimination law in labour markets. This article pursues two connected arguments through a comparison of rules for enforcing non-discrimination law in labour markets in Britain and Italy. First, it argues that enforcing non-discrimination law in labour markets is best achieved when responsive governance, repressive regulation and mainstreaming equality law are combined. Second, the article submits that diversity of national legal orders within the EU is not necessarily detrimental, as it offers opportunities for mutual learning across legal systems.The notion of mutual learning across systems is proposed in order to analyse the transnational migration of legal ideas within the EU. Such migration has been criticized in debates about the ‘transplantation’ of legal concepts or legal irritation through foreign legal ideas, in particular by comparative labour lawyers. However, EU harmonization policies in the field of non-discrimination law aim to impact on national labour laws. The article develops the notion of mutual learning across legal systems in order to establish conditions for transnational migration of legal ideas, and demonstrates the viability of these concepts by applying them to the field of non-discrimination law

Setting the Rules of the Game: Mega-Regionals and the Role of the WTO

Faced with a WTO in a state of paralysis, large developed trading nations have shifted their attentions to other fora to pursue their trade policy objectives. In particular, preferential trade agreements (PTAs) are now being used to promote the regulatory disciplines that were previously rejected by developing countries at the multilateral level. These so-called ‘deep’ or ‘21st century’ PTAs address a variety of issues, from technical norms, procurement, investment protection and intellectual property rights to social and environmental protection. Moreover, recently, developed countries have sought to negotiate PTAs which are large in scale, both in terms of economic size and geographical reach, including the so-called ‘mega-regional’ PTAs, such as the EU-US Transatlantic Trade and Investment Partnership, the EU-Japan PTA, the Transpacific Partnership, and the China-backed Regional Comprehensive Economic Partnership. These mega-regional PTAs are distinctive not just in terms of their sheer size and the breadth and depth of issues addressed, but also because some of their proponents readily admit that one of the central aims pursued by such agreements is to design global rules on new trade issues. In other words, these agreements are being conceived as alternatives to multilateral rule making at the WTO level. The proliferation of 21st century trade deals raises important questions concerning the continued relevance of the WTO as a global rule-making venue, and the impact that the regulatory disciplines promoted in such agreements will have on both developing and developed countries. This paper discusses the emerging features of an international trading system that is increasingly populated by large-scale PTAs and discusses some of the points of tension that arise from such practice. Firstly, it examines instances of horizontal tension resulting from the proliferation of PTAs, particularly the extent to which such PTAs represent a threat or multilateral trade governance. Secondly, it looks at an example of vertical tension by examining the manner in which the imposition of regulatory disciplines through trade agreements can undermine the ability of countries, especially developing countries, to pursue legitimate public interest objectives. Finally, the paper considers a number of steps that could be considered to address some of the adverse effects associated with the fragmentation of the international trading system, including the option of embracing variable geometry within the WTO framework and the need to develop mechanisms that provide flexibility for developing countries in the implementation of regulatory disciplines.

Cumulative or sequential assessment during hermit crab shell fights: effects of oxygen on decision rules

Agonistic interactions between animals are often settled by the use of repeated signals which advertise the resource-holding potential of the sender. According to the sequential assessment game this repetition increases the accuracy with which receivers may assess the signal, but under the cumulative assessment model the repeated performances accumulate to give a signal of stamina. These models may be distinguished by the temporal pattern of signalling they predict and by the decision rules used by the contestants. Hermit crabs engage in shell fights over possession of the gastropod shells that they inhabit. During these interactions the two roles of signaller and receiver may be examined separately because they are fixed for the duration of the encounter. Attackers rap their shell against that of the defender in a series of bouts whereas defenders remain tightly withdrawn into their shells for the duration of the contest. At the end of a fight the attacker may evict the defender from its shell or decide to give up without first effecting an eviction; the decision for defenders is either to maintain a grip on its shell or to release the shell and allow itself to be evicted. We manipulated fatigue levels separately for attackers and defenders, by varying the oxygen concentration of the water that they are held in prior to fighting, and examined the effects that this has on the likelihood of each decision and on the temporal pattern of rapping. We show that the vigour of rapping and the likelihood of eviction are reduced when the attacker is subjected to low oxygen but that this treatment has no effect on rates of eviction when applied to defenders. We conclude that defenders compare the vigour of rapping with an absolute threshold rather than with a relative threshold when making their decision. The data are compatible with the cumulative assessment model and with the idea that shell rapping signals the stamina of attackers, but do not fit the predictions of the sequential assessment game.