We consider three accepted truths about iris biometrics, involving pupil dilation, contact lenses and template aging. We also consider a relatively ignored issue that may arise in system interoperability. Experimental results from our laboratory demonstrate that the three accepted truths are not entirely true, and also that interoperability can involve subtle performance degradation. All four of these problems affect primarily the stability of the match, or authentic, distribution of template comparison scores rather than the non-match, or imposter, distribution of scores. (...) In this sense, these results confirm the security of iris biometrics in an identity verification scenario. We consider how these problems affect the usability and security of iris biometrics in large-scale applications, and suggest possible remedies. (shrink)

Patient safety has only recently been subjected to wide-spread systematic study. Healthcare differs from other high risk industries in being more diverse and multi-contextual, and less certain and regulated. Also many patient safety problems are low-frequency events associated with many, varied contributing factors. The subject of this paper is the epistemology of patient safety (the science of the method of finding out about patient safety). Patient safety research is considered here on the background of a risk management framework which requires (...) researchers to: • Understand the context - as a subset of healthcare quality, services and systems research, with technical and human behavioural (cultural) components and a range of external and internal organisational influences, a wide range of research disciplines is necessary • Identify the risks - identify the things that go wrong and the frequency and nature of different types of incidents from sources such as medical record review, observational studies, audit, incident and medico-legal reports • Analyse the risks - deconstruct the things that go wrong, identifying contributing factors and trying to detect trends and patterns in contributing factors, detection, mitigation factors, ameliorating factors and actions taken to reduce risk • Evaluate the risks - decide on priorities, identifying preventive and corrective strategies and judging the risk- and cost-benefit of potential corrective strategies such as standardisation or simplification of a process or device • Manage the risk - evaluate and scope preventive and/or corrective strategies and then implement these, or place the problem on a risk register pending solution, or accept that what is needed is unaffordable • Communicate and consult - use interactive sessions, audit, on-going feedback, reminders and patient mediated prompts • Monitor and review the state of the problem - get baseline trends and patterns so that changes can be tracked and properly attributed to an intervention A hierarchy of levels of evidence has been proposed for clinical research and we argue that insufficient weighting has been given to lower ranked levels of research and to qualitative research, although critical interpretive synthesis is now gaining acceptance in mainstream thinking (e.g. by the Cochrane Collaboration). Fundamental challenges remain including how to grasp the elusive concept of patient safety, how to quantify, characterise and cost the problems, how to judge the extent to which harm can be attributed to errors, violations or system failures, how to identify contributing factors and the extent to which they can be implicated, how to judge whether incidents or their precursors are preventable, how to generate strong evidence to make healthcare safer and how to translate research into practice. Future directions include addressing the mundane as well as rare, dramatic events, and developing further research in non-hospital settings and in developing countries. In summary, a mixture of qualitative and quantitative methods, using information from all available data sources and combining retrospective, real time and prospective study designs, is necessary to address some of the more difficult patient safety problems. (shrink)

Whittaker, following Siebeck, pointed out the important role Plotinus assigns to the functions of imagination in psychic life. Imagination is the terminus ad quern of all properly human conscious experience; it is that faculty of man without which there can be no conscious experience. The sensitive soul is an imaginative soul below which there is Nature, or vegetative soul, which acts without being conscious. When the functions of reason are added to sensation to produce a rational human being, there is (...) conscious discursive thought as well as conscious sensation; and since the sensitive soul cannot be responsible for the imaging of rational concepts, Plotinus asserts the existence of a conceptual imagination. (shrink)

Reform of the federal income tax system has become a perennial item on the domestic policy agenda of the United States, although there is considerable uncertainty over specifics. Indeed the recent report of the President's Advisory Panel on Federal Tax Reform recommended not one but two divergent policy directions. In Fundamental Tax Reform, top experts in tax policy discuss a wide range of issues raised by the prospect of significant tax reform, identifying the most critical questions and considering whether the (...) answers are known, unknown--or unknowable. The debates over tax reform usually concern the advantages and disadvantages of income-based taxation as opposed to any of the several alternative forms of consumption-based taxation. The book opens with chapters that discuss the strengths, weaknesses, and political feasibility of these options. Other chapters consider the effect of tax reform on businesses, especially their investment behavior, and include a discussion of possible problems in any transition to a consumption-based tax; international taxation issues arising in an era of globalization; and individual behavioral response to tax reform, including a view of the topic from the perspective of the relatively new field of behavioral economics. ContributorsRosanne Altshuler, Alan J. Auerbach, John W. Diamond, Harry Grubert, Arnold C. Harberger, Kevin A. Hassett, Thomas J. Kniesner, Laurence J. Kotlikoff, Edward J. McCaffery, Kathryn Newmark, David Rapson, Daniel Shaviro, Joel Slemrod, James P. Ziliak, George R. ZodrowDiscussants James Alm, Henry J. Aaron, Charles L. Ballard, Leonard E. Burman, Robert S. Chirinko, Robert D. Dietz, Malcolm Gillis, Roger H. Gordon, Jane G. Gravelle, Timothy S. Gunning, James M. Poterba, Thomas S. Neubig, Alan Viard, George Yin John W. Diamond is Edward and Hermena Kelly Fellow in Tax Policy and Adjunct Professor of Economics at the Baker Institute for Public Policy, Rice University. George R. Zodrow is Professor of Economics and Rice Scholar at the Baker Institute and International Research Fellow at the Centre for Business Taxation, Oxford University. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Thomas Abbt and the Formation of an Enlightened German “Public”Benjamin W. RedekopScholarly interest in the emergence of a “public sphere” and “public opinion” in eighteenth-century Europe remains strong, and with good reason. The ideological construct of a modern public in Europe “was a characteristic product of the Enlightenment, and it marked one of the critical zones of intersection between Enlightenment discourse and a broad range of socio-economic and institutional (...) changes.” 1 Analysis of the emerging figure of “the public” helps illuminate the relationship between intellectual and material culture, between “Enlightenment” and society. The recognition of the constitutive nature of language and its role in the interplay between “meaning” and “experience” 2 lead one to take seriously terms like “the public” and “public opinion” as important links between linguistic and social domains. Text and context merge into one as social entities like “the public” become rhetorical ones, and vice-versa.Keith Baker, for example, resolves the contextual dimension of “public opinion” in France into the textual one, whereby it emerges as a “rhetorical figure” or “political invention” in the latter decades of the eighteenth century. 3 Others stay closer to the social domain, including the salons of Paris, to look for the emergence of the notion of rational public opinion. 4 Taken together, these are two sides of the same coin—an emerging sphere of “public” discourse carried on by “private” individuals, and a more private sphere in which public discursivity was nurtured. 5 [End Page 81]In this article I explore these themes in a German context, focusing on the writings of Thomas Abbt (1738–66) as an attempt to grapple with the exigencies of German social and intellectual life in a novel fashion. Making use of a variety of European sourc es, Abbt—an academic with broad interests—strove in On Dying for the Fatherland (1761), On Merit (1765), and in his contributions to the seminal journal Letters Concerning the Newest Literature to conceptualize and to create a sense of citizenship and the “common good” which cut across the various divisions of German society, uniting all orders into a greater and harmonious whole or Publikum (public). The written word was the primary vehicle available for this simultaneous mo vement of enlightenment and socio-political formation, and Abbt’s works represent an early attempt to inscribe a public sphere—to create a space in which it became possible for individuals to think, talk, and act in reference to a larger socio-political whole. While Prussian patriotism was behind his initial foray into the topic of the public sphere in On Dying for the Fatherland, Abbt’s On Merit reveals an expansion in perspective, and with it the emergence of “the public” as a moral and s ocio-political point of reference. There is a good degree of continuity, however, between the two works, concerned as they are with overcoming the basic German problem of a fragmented public sphere with enlightened arguments designed to lead readers to lo cate themselves and their well-being in an enlarged societal frame.While at least one commentator has argued that Abbt was seeking to write for the common German Volk, 6 his primary audience was clearly that of the middling and higher orders. 7 The general problem Abbt addressed, however, was that of reconciling Enlightenment and reform with the entire spectrum of German society. This entailed the exploration of new, informal, and inclusive terms and modes of address: an available term was “the public,” and the mode of address a writing style which transformed ancient forms of public oratory into text—the public speaker became, under modern circumstances, the public writer.It is in this sense that Abbt was original and influential. Johann Gottfried Herder, Friedrich Nicolai, Moses Mendelssohn, J. G. Zimmerman, Friedrich Schiller, and others were moved in one way or another by Abbt’s writings. 8 [End Page 82] Herder in particular was stimulated by Abbt’s works, and Herder’s project was informed by the same kinds of socio-political concerns outlined here in relation to Abbt. 9 G. E. Lessing’s work also reflected a concern with the formation of a broader Publikum, as he mediated... (shrink)

This paper is based on a semantic foundation of quantum logic which makes use of dialog-games. In the first part of the paper the dialogic method is introduced and under the conditions of quantum mechanical measurements the rules of a dialog-game about quantum mechanical propositions are established. In the second part of the paper the quantum mechanical dialog-game is replaced by a calculus of quantum logic. As the main part of the paper we show that the calculus of quantum logic (...) is complete and consistent with respect to the dialogic semantics. Since the dialoggame does not involve the 'excluded middle' the calculus represents a calculus of effective (intuitionistic) quantum logic. In a forthcoming paper it is shown that this calculus is equivalent to a calculus of sequents and more interestingly to a calculus of propositions. With the addition of the 'excluded middle' the latter calculus is a model for the lattice of subspaces of a Hilbert space. (shrink)

The article argues against the commonly held 'green glasses' interpretation of Kant's "a priori", where any one's familiar experience must be seen as integrated by space and time and the categories. Such an interpretation does not answer Hume's problem, Which was whether any necessary connection could be found in experience. For the connections of familiar experience are customary and contingent. Passages from Kant are cited to show that he meant by 'objective experience', not familiar experience, but that body of scientific (...) observation which has been connected according to law. The "a priori" turns out to be what the scientist finds necessary for the possibility of such a connected experience. (shrink)