Blockchain Papers

Frédéric Lasserre

No abstract is available for this record.

Boaz Barak

We present the first constant-round non-malleable commitment scheme and the first constant-round non-malleable zero-knowledge argument system, as defined by Dolev, Dwork and Naor (1991). Previous constructions either used a non-constant number of rounds, or were only secure under stronger setup assumptions. An example of such an assumption is the shared random string model where we assume all parties have access to a reference string that was chosen uniformly at random by a trusted dealer. We obtain these results by defining an adequate notion of non-malleable coin-tossing, and presenting a constant-round protocol that satisfies it. This protocol allows us to transform protocols that are non-malleable in (a modified notion of) the shared random string model into protocols that are non-malleable in the plain model (without any trusted dealer or setup assumptions). Observing that known constructions of a non-interactive non-malleable zero-knowledge argument systems in the shared random string model (De Santis et. al., 2001) are in fact non-malleable in the modified model, and combining them with our coin-tossing protocol we obtain the results mentioned above. The techniques we use are different from those used in previous constructions of non-malleable protocols. In particular our protocol uses diagonalization and a non-black-box proof of security (in a sense similar to Barak's zero-knowledge argument (2001)).

John Watrous

In this paper we propose a definition for (honest verifier) quantum statistical zero-knowledge interactive proof systems and study the resulting complexity class, which we denote QSZK/sub HV/. We prove several facts regarding this class, including: the following problem is a complete promise problem for QSZKHV: given instructions for preparing two mixed quantum states, are the states close together or far apart in the trace norm metric? This problem is a quantum generalization of the complete promise problem of Sahai and Vadhan (1997) for (classical) statistical zero-knowledge; QSZK/sub HV/ is closed under complement; QSZK/sub HV//spl sube/PSPACE. (At present it is not known if arbitrary quantum interactive proof systems can be simulated in PSPACE even for one-round proof systems); any polynomial-round honest verifier quantum statistical zero-knowledge proof system can be simulated by a two-message (i.e., one-round) honest verifier quantum statistical zero-knowledge proof system. Similarly, any polynomial-round honest verifier quantum statistical zero-knowledge proof system can be simulated by a three-message public-coin honest verifier quantum statistical zero-knowledge proof system. These facts establish close connections between classical statistical zero-knowledge and our definition for quantum statistical zero-knowledge, and give some insight regarding the effect of this zero-knowledge restriction on quantum interactive proof systems. The relationship between our definition and possible definitions of general (i.e., not necessarily honest) quantum statistical zero-knowledge are also discussed.

Manoj Prabhakaran, Alon Rosen, Arun Sahai

We show that every language in NP has a (black-box) concurrent zero-knowledge proof system using O/spl tilde/(log n) rounds of interaction. The number of rounds in our protocol is optimal, in the sense that any language outside BPP requires at least /spl Omega//spl tilde/(log n) rounds of interaction in order to be proved in black-box concurrent zero-knowledge. The zero-knowledge property of our main protocol is proved under the assumption that there exists a collection of claw free functions. Assuming only the existence of one-way functions, we show the existence of O/spl tilde/(log n)-round concurrent zero-knowledge arguments for all languages in NP.

Brian J. Driessen, Nader Sadegh

We consider the problem of discrete-time iterative learning control (ILC) for position trajectory tracking of multiple-input, multiple-output systems with Coulomb friction, bounds on the inputs, and equal static and sliding coefficients of friction. Only position measurements are assumed available. No velocity measurements are assumed available. We present an ILC controller and a proof of convergence to zero tracking error, provided the associated learning gain matrices are scalar-scaled with a sufficiently small positive scalar. We also show that non-diagonal learning gain matrices satisfying the same prescribed conditions do not lead to the same convergence property. To the best of our knowledge, for problems with Coulomb friction, this paper represents a first convergence theory for the discrete-time ILC problem with multiple-inputs and multiple-bounded-outputs; previous work presented the theory only for the single-input, single-output problem.

Boaz Barak, Oded Goldreich

We put forward a new type of computationally-sound proof systems, called universal-arguments, which are related but different from both CS-proofs (as defined by Micali, 2000) and arguments (as defined by Brassard et al., 1986). In particular, we adopt the instance-based prover-efficiency paradigm of CS-proofs, but follow the computational-soundness condition of argument systems (i.e., we consider only cheating strategies that are implementable by polynomial-size circuits). We show that universal-arguments can be constructed based on standard intractability assumptions that refer to polynomial-size circuits (rather than assumptions referring to subexponential-size circuits as used in the construction of CS-proofs). As an application of universal-arguments, we weaken the intractability assumptions used in the recent non-black-box zero-knowledge arguments of Barak (2001). Specifically, we only utilize intractability assumptions that refer to polynomial-size circuits (rather than assumptions referring to circuits of some "nice" super-polynomial size).

Jonathan D. Moreno

In 1986, the German sociologist Ulrich Beck published the first edition of his book, Risk Society.1 Beck's book has attained wide popularity, especially in Europe, for his analysis of the distance between scientific expertise and popular opinion in the understanding of potential harms. Time and again, Beck points out, the public complains that there is a harmful process at work, while the scientists who are appointed by authorities to assess the complaints conclude that there is no objective basis for concern. Too often, though, the scientific conclusions are advanced without involving the public and without taking into account conditions outside of the laboratory. Subsequent experiences, such as the Mad Cow disaster in British livestock, have only reinforced the problem. Public skepticism about genetically modified organisms and the food supply can be traced to the same roots. On both sides of the Atlantic, the example of HIV in the blood supply, the halting management of the crisis, and the resulting loss of public confidence in the system, constitute an all-too-familiar case for readers of this journal. These kinds of examples and the conditions that Beck describes and explicates helped lead to the development of a policy standard, again especially in Europe, called the precautionary principle. In a 1992 statement, the European Environment Agency gave a succinct statement of the principle: [I]n order to protect the environment, a precautionary approach should be widely applied, meaning that where there are threats of serious or irreversible damage to the environment, lack of full scientific certainty should not be used as a reason for postponing cost-effective measures to prevent environmental degradation. Further, The precautionary principle permits a lower level of proof of harm to be used in policy-making whenever the consequences of waiting for higher levels of proof may be very costly and/or irreversible (emphasis added).2 Paradoxically, technologic advancement itself is the source of the risks that concern us. In other words, scientific expertise has created the very conditions that society now doubts the experts fully appreciate. In Risk Society, Beck defines risk as “a systematic way of dealing with hazards and insecurities induced and introduced by modernization itself.” He goes on, “Risks, as opposed to older dangers, are consequences which relate to the threatening force of modernization and to its globalization of doubt.” The social and political conditions that affect current issues in transfusion medicine are thus part of a much larger “globalization of doubt” about expertise. Although he does not allude to transfusion medicine per se, it is a paradigm case of risk in the sense that Beck writes about, for it has been a modernizing development in medical care and the risks it brings about would not exist without that modernization. The tensions within a “risk society” are brought to the surface when a new incident reignites doubt, such as concerns about West Nile virus in the summer of 2002. Sensitized by previous failures to satisfy public concern, responsible officials leap into action, often shifting their attention and energy away from known and measurable risks to persuade society that the unknown and often nonmeasurable risk is being taken seriously. This reaction, while understandable in light of the critique leveled by Beck and many others, should give us pause. Along with policies intended to drastically reduce risk, it is an example of the way that the precautionary principle has been both transformed into a dogma and taken out of its original context. I call these tendencies “creeping precautionism” because the adoption of a precautionary stance may not even be noticed until it is too late, and because a reasonable principle can easily be turned into a self-defeating ideology. Consider two recent policies that public health and blood industry experts have cited in conversation as examples that might reflect creeping precautionism: p24 antigen testing for HIV, which may have prevented one case per year at a cost of tens of millions a year; and deferral of donors who have been European residents, when the risk of CJD risk remains highly theoretical with no documented case of transmission, and hundreds of thousands of units have been lost as a result. I am no authority on the complex medical and public health issues involved, but suppose for the sake of argument that these policies raise valid questions. How did they come to pass? Clearly many elements came into play in these policy decisions. One that has not previously been identified is the fact that, as these policies were being formed, the precautionary principle came to have a great deal of influence in environmental health circles. In fact, I believe that we live in a period in which the principle has, without argument and often without conscious awareness, both been taken out of context, applied to problems other than catastrophic health concerns, and misinterpreted. The original context was environmentalism, where ecologic complexities and uncertainties present risks that, for all intents and purposes, may truly be inestimable and irreversible. Those conditions may not apply in other policy contexts. The misinterpretation has been to suppose that precautionism requires that only zero risk is acceptable, or at least something quite close to zero risk. Even advocates of the principle would recognize these subtle shifts in thinking as errors. In particular, it is clear that no action or inaction is risk free, and that any decision has opportunity costs. The opportunity costs of precautionism in the blood industry are, among others, the loss of many usable units of blood and the alienation of potential donors. I am not arguing that the policies in question are without merit nor that they should be repealed. Rather, I urge that a discussion begin in the blood services community about whether unwarranted precautionism has in fact crept into policymaking. This discussion should also take into account the peculiar stresses upon the role of expertise in a modern democracy. To step back for a moment, it is useful to recall the classical origins of the idea of expertise. In his seminal work, The Republic, Plato uses an allegory to characterize the situation of the truly knowledgeable person. He spins a tale about a group of slaves bound to their places since birth, unable to turn their heads, and only able to view a wall in front of them. Behind them are carried ordinary objects, whose shadows fall upon the wall. Knowing nothing better, the slaves assume that the shadows are the real objects. Now suppose, Plato continues, a slave manages to break his bonds and escape to the mouth of the cave. Unaccustomed to the light, he will at first be blinded by the sun, then realize to his horror that all his life what he has thought was reality was merely illusion. He tries to enlighten (pun intended) his comrades, but they mock him as mad. Discouraged, he takes his place among the slaves again. The allegory implies that knowledge is painful, hard to achieve, and subject to ridicule by the ignorant. This is the uncomfortable position of the expert. The problem is especially grave in medicine, whose practitioners are supposed to be sensitive to the uninitiated. Yet, too much sensitivity is incompatible with the detachment and decorum that the physician requires to be effective. Sir William Osler, generally regarded as the father of internal medicine, commented on this dilemma of the health care expert over a century ago. Imperturbability. . . . It is the quality which is most appreciated by the laity though often misunderstood by them; and the physician who has the misfortune to be without it, who betrays indecision and worry, and who shows that he is flustered and flurried in ordinary emergencies, loses rapidly the confidence of his patients.3 I write as a product and professor of the bioethical revolution in medicine, which is characterized by a deep suspicion of expertise, manifested as the insistence on informed consent and truth telling by doctors. This revolution is only about 30 years old in practice and would have shocked my father, a 1917 graduate of the University of Vienna medical school. The emergence of bioethics in the 1970s (my father died in 1974, too soon to experience the sweeping changes in medical ethics) is of a piece with the appearance of the precautionary principle of the 1980s. Both are rooted in skepticism of professional authority, and both have advocated lay involvement in medical decisions. I do not advocate repudiating the new medical ethics. As the Yale University psychiatrist and law professor Jay Katz has long pointed out, the doctor-patient relationship was for eons characterized by a doctor-dominated paradigm that is best left behind. Yet, I worry that the critique of modernism, of expertise, has swung too far. In the clinical setting, I have seen this phenomenon manifested as the reluctance of physicians to give advice to patients who are facing a complex treatment decision. Often I hear complaints that doctors respond to patients’ requests for guidance with the demurrer that it is their decision, that they must exercise their self-determination. This is a case of turning patient autonomy into a shield behind which doctors can hide. The ethical principle of autonomy should not be an excuse for abandoning the counseling that patients crave. Similarly, in the long run I think it is bad for the profession to give up the moral authority that comes with expertise. Perhaps those with expertise in public health and blood should open a conversation about whether they have succumbed to creeping protectionism in an honest attempt to learn from the horrors of the HIV experience. I cannot say whether this is the case, only that the signs point to this possibility. On the importance of a philosophical view of scientific expertise, consider Osler again. A rare and precious gift is the Art of Detachment, by which a man may so separate himself from a life-long environment as to take a panoramic view of the conditions under which he has lived and moved: it frees him from Plato's den long enough to see the realities as they are, the shadows as they appear. Could a physician attain to such an art he would find in the state of his profession a theme calling as well for the exercise of the highest faculties of description and imagination as for the deepest philosophic insight.4 In our time, scientists have learned about the pitfalls of an aristocratic attitude. The challenge is to balance those lessons with society's continuing need for unshackled expertise. To this end, efforts should be made to develop evidence that quantifies, or at least aids in prioritizing risks, with the goal of evidence-based risk assessment. Scientists and physicians should then recognize their social obligation to participate in policy debates in which their expert opinions can help the public balance imminent and more remote risks and evaluate the costs associated with risk-minimizing initiatives. In this way, perhaps we can all meet the Platonic challenge of doing science in a democracy.

André Adelsbach, Ahmad‐Reza Sadeghi

Digital watermarking is a promising technology for protecting intellectual property rights on digital content. Resolving authorship-disputes was one of the first and most propelling applications of robust digital watermarks, and much research effort has gone into protocols for resolving authorship-disputes by means of digital watermarks. Unfortunately, previous proposals lack formal definitions of their trust model, their assumptions, and requirements they should fulfill. This lack of formal definitions makes security proofs for such protocols impossible and many dispute resolving protocols, claimed to be secure, can be shown to be insecure. In this paper we set off to rigorously defining dispute resolving schemes based on a reasonable formal definition of "authorship." Building on this formal fundament, we analyze the most important proposals for dispute resolving, and discuss their connection to our authorship model. We show that existing proposals suffer from two major problems: First, they require an unnecessary high level of trust in the dispute resolving party. The second and even more serious is that the winner of the dispute is not guaranteed to be the rightful author of the disputed work (conclusiveness problem). As solutions, we propose dispute resolving schemes based on zero-knowledge watermark detection and asymmetric watermarking schemes.

J.D. Creutin, M. Muste, A.A. Bradley, S.C. Kim · 5 authors

No abstract is available for this record.

김용웅, 차미숙

This paper aims to improve local financial system for socio-economic development at local and regional levels. It has been widely known among financial experts and planners that local financial system is inadequate to meet the increasing needs for local governments to provide various local services. Local financial system needs to be improved particularly for the achievement of decentralization and regional balanced development, which have been selected as major national agenda of the Roh Mu-hyun administration. The first half of this paper reviews current status and problems of local finance in terms of its relative size against national finance, ratio of local revenue against total local finance, and eff iciency in using local finance for regional development. It suggests that unlike many previous arg uments, the major problem of local finance is not its over-all size but its inequal distribution among regions and its inefficient use for regional development. The paper introduces the concept of local financial coefficient to analyze the inequality of local financial capability, particularly between the Capital region and rest of regions in Korea. It shows that the national finance has been overly allocated in the Capital regions while it has been insufficiently allocated in other regions. Furthermore, this paper clearly indicates that current proposals for the improvement of local financial system are likely to widen regional inequalities and weaken national financial capability to promote regional balanced development. The second half of this paper proposes some policy prescriptions to improve local financial system in the context of balanced regional development. It suggests that it is necessary to expand local financial capability to promote regional development projects in less prospe rous regions and to establish a regional governance system to coordinate regional development projects between the central and local governments for the efficient use of financial re sources at local and regional level.

Floribert Ngaruko

This article analyzes how administrative decentralization can improve the provision of social services in Africa. It uses political, economic, and historical approaches, to investigate the bureaucratic dysfunctions that administrative decentralization may reduce. It argues that administrative decentralization can overcome the all-time challenge for African central governments to broadcast authority over harsh and sparsely inhabited territories. Also, by tackling the use of public employment and wages to leverage distributive politics, it may reduce the distortions affecting the financing of public services, and which particularly undermine the quality of education. Administrative decentralization may also enhance merit-based appointments and promotions of bureaucrats by reducing the propensity to resort to public employment and wages as a means for political officials to reward loyalty and to recruit fellows. Finally, administrative decentralization may leverage effectively civil service reforms seeking to align central bureaucracies with the objective of poverty reduction through enhanced service delivery. Attention is drawn, however, to the conflicts that may arise, as administrative decentralization will come to threaten vested interests. The paper argues that for reformer international institutions, handling situations of political crises and learning how to use them to leverage reform will be critical for the success of administrative decentralization in Africa.

William L. Ledger

No abstract is available for this record.

Sergio Rajsbaum

The Distributed Computing Column covers the theory of systems that are composed of a number of interacting computing elements. These include problems of communication and networking, databases, distributed shared memory, multiprocessor architectures, operating systems, verification, internet, and the web.This issue consists of the paper "Reconstructing Paxos" by Romain Boichat, Partha Dutta, Svend Frølund, and Rachid Guerraoui. Many thanks to them for contributing to this issue.The celebrated Paxos algorithm of Lamport implements a fault-tolerant deterministic service by replicating it over a distributed message-passing system. In a companion paper [2], we presented a deconstruction of the algorithm by factoring out its fundamental algorithmic principles within two abstractions: an eventual leader election and an eventual register abstractions. Using those abstractions, we show in this paper how to reconstruct, in a modular manner, powerful variants of Paxos. In particular, we show how to (1) alleviate the need for stable storage access if some processes remain up for sufficiently long, (2) augment the resilience of the algorithm against unstable processes, (3) enable single process decision with shared commodity disks, and (4) reduce the number of communication steps during stable periods of the system.The Island of Paxos used to host a great civilisation which had developed a sophisticated parttime parliament protocol. Paxons codified various aspects of their parliament protocol which enabled them to easily adapt the protocol to specific functioning modes throughout the seasons. In particular, during winter, the parliament was heated and some legislators did never leave the chamber: their guaranteed presence helped alleviate the need for the writing of decrees on ledgers. This was easy to obtain precisely because the subprotocol used to "store and lock" decrees was precisely codified. In spring, and with the blooming days coming, some legislators could not stop leaving and entering the parliament. Their indiscipline prevented progress in the protocol. However, as the election subprotocol used to choose the parliament president was also precisely codified, the protocol could easily be adapted to cope with indisciplined legislators. During summer, very few legislators were in the parliament and it was hardly possible to pass any decree because of the lack of the necessary majority. Fortunately, it was easy to modify the subprotocol used to store and lock decrees and devise a powerful technique where a single legislator could pass decrees by directly accessing the ledgers of other legislators. Fall was a protest season and citizens wanted a faster procedure to pass decrees. Paxons noticed that, in most periods, messengers did not loose messages and legislators replied in time. They could devise a variant of the protocol that reduced the number of communication steps needed to pass decrees during those periods. Again, this optimisation was obtained through a simple refinement of the subprotocol used to propose new decrees.

Larry M. Coutts, Frank Schneider, Andrew Johnson, Paul McLeod

ABSTRACT This research focuses on developing strategies for the more effective recruitment and selection of community policing (CP) officers. University students (N = 178) reviewed descriptions of the law enforcement policing (LEP) and (CP) models. After rating each model on several evaluative criteria, one-half of the participants completed a measure of personality (Neo Personality Inventory; Costa & McCrae, 1992), while the other half completed a measure of vocational interest type (Self-Directed Search; Holland, Powell & Fritzsche, 1997). The dimensions of personality and vocational interest type were correlated with the ratings of the models. The ratings of the models supported the hypotheses that students would equate extant policing with LEP, prefer to work under CP, and experience increased interest in a career in policing once informed of the emergence of CP. These results were interpreted as suggesting that if the public were better informed about CP, the police would attract a higher number of job applicants. In addition to the above, correlational analyses revealed some conceptually meaningful relationships among the individual difference variables and the evaluations of the models. These results were interpreted as suggesting the possibility of selecting recruits whose personal characteristics represent a good fit with CP. Changing from a traditional law enforcement policing (LEP) model to a community policing (CP) model has been a major objective of North American police organizations since the 1980s (Chacko & Nancoo, 1993; Trojanowicz & Bucqueroux, 1990). It may be argued, however, that this change requires adopting a new philosophy and strategy of policing. For example, whereas the LEP model is based on a highly centralized organizational structure, is incident driven, and emphasizes reactive response in combating crime, the CP model is more organizationally decentralized, proactive, and entails close police-community partnerships in the identification, analysis, and solution of local crime and disorder problems (Leighton, 1994; Trojanowicz & Bucqueroux, 1990). Given the above, it is clear that a move toward a CP model involves considerable changes in the role and concomitant skills required of front-line police officers (Clairmont, 1991; Meese, 1993; Trojanowicz & Bucqueroux, 1990). For example, compared with traditional LEP officers, CP officers are called upon to demonstrate more of the following: autonomous functioning, decision making ability, innovative and analytical problem solving, effective communication with community leaders, groups, and social service agencies, and ability to plan and organize community crime prevention programs. In addition, some observers have noted that the expanded role and skills required of CP officers have significant implications for both police recruitment and selection (see e.g., Getting an Edge, 1999; Hoath, Schneider & Starr, 1998; Metchik & Winton, 1995). For example, Metchik and Winton (1995) reviewed the typical 'screening out' practices of traditional police selection and argued that CP requires more positively oriented selection criteria and procedures. This is especially true in light of the fact that significant numbers of police officers, many of whom were selected and trained under the traditional LEP model, have resisted accepting CP (Clairmont, 1991; Dicker, 1998; Roberg, 1994; Scrivner, 1995; Vinzant & Crothers, 1994). The extent to which such resistance is problematic is underscored not only by existing research which has clearly demonstrated the effectiveness of CP, but also by the enormous resources invested in the implementation of CP. In the United States, for example, since 1994 more than $7.5 billion has been invested by the Office of Community Oriented Policing Services (COPS) to promote CP in law enforcement agencies (National Criminal Justice Reference Service, 2002). …

Loukas Tsoukalis

Author Webpage More than fifty years after it all began, regional integration in Europe has developed into a complex system, with no precedent in history and no rival in other parts of the contemporary world. Old and new nation‐states in Europe have joined in: some still anxiously waiting in the antechamber and only a very few willingly staying out (for how long?). Successive rounds of deepening and widening, meaning in plain English that regional integration becomes ever closer and also extends into new areas of policy while membership continues to grow, constitute the best proof of success. The European Union is very much alive and delivering the goods, perhaps against the odds and contrary to all kinds of doomsday scenarios. Unlike empires in the past, European integration is centred on democratic systems and the principle of free association. No country has been forced to join or stay against the collective will of its citizens. It must therefore be judged as satisfying real needs, at least for a sufficient number of people, in government, among interest groups, or among simple citizens who have been ready to lend it their active or passive support.

Kenneth M. Anderson, Aaron Andersen, Neet Wadhwani, Laura M. Bartolo

The Metis project is developing workflow technology designed for use in digital libraries by avoiding the assumptions made by traditional workflow systems. In particular, digital libraries have highly distributed sets of stake-holders who nevertheless must work together to perform shared activities. Hence, traditional assumptions that all members of a workflow belong to the same organization, work in the same fashion, or have access to similar computing platforms are invalid. The Metis approach makes use of event-based workflows to support the distributed nature of digital library workflow and employs techniques to make the resulting technology lightweight, flexible, and integrated with the Web. This paper describes the conceptual framework behind the Metis approach as well as a prototype which implements the framework. The prototype represents a proof-of-concept of the Metis framework and approach as we show how it can both model and execute a peer review workflow drawn from a real-world digital library. After describing related work, the paper concludes with a discussion of future research opportunities in the area of digital library workflow and outlines how Metis is being deployed to a small set of digital libraries for additional evaluation.

Ronald Zhao

No abstract is available for this record.

Oliver Gassmann, Maximilian von Zedtwitz

The past years have seen a decentralization of R&D to local markets and centres‐of‐excellence. Supported by modern information and communication technologies, ‘virtual project teams’ were formed to facilitate transnational innovation processes. With their boundaries expanding and shrinking flexibly with changing project necessities, virtual teams are believed to be an important element in future R&D organization. Based on 204 interviews with R&D directors and project managers in 37 technology‐intensive multinational companies we identify four distinct forms of virtual team organizations used to execute R&D projects across multiple locations. Ordered by increasing degree of central project coordination, these four team concepts are based on: (1) decentralized self‐organization, (2) a system integrator as a coordinator, (3) a core team as a system architect, and (4) a centralized venture team. Our contingency approach for organizing a transnational R&D project is based on four principal determinants: (1) the type of innovation (radical/incremental), (2) the systemic nature of the project (systemic/autonomous), (3) the mode of knowledge involved (tacit/explicit), and (4) the degree of resource bundling (complementary/redundant). According to our analysis, the success of virtual teams depends on the appropriate consideration of these determinants.

W. Jack

Nicaragua has embarked on a reform of the way in which publicly provided medical care is organized and financed. A principal feature of the reforms includes a decentralization of decision-making authority coupled with an increase in local accountability. Local decision-making authority has been increased by allowing managers more freedom to allocate inputs. Accountability has been strengthened by stipulating what is expected of hospitals and health centres in the form of performance agreements, and tying rewards (i.e. bonuses) to the satisfaction of these requirements provides incentives. This paper provides a critical assessment of these reforms, and presents some early evidence of their effects.

Jeremy E. P. Dahl, J. Michael Moldowan, Torren M. Peakman, Jon C. Clardy · 13 authors

No abstract is available for this record.

Roman Inderst, Holger M. Müller

Abstract We study optimal financial contracting for centralized and decentralized firms. Under centralized contracting, headquarters raises funds on behalf of multiple projects. Under decentralized contracting, each project raises funds separately on the external capital market. The benefit of centralization is that headquarters can use excess liquidity from high cash‐flow projects to buy continuation rights for low cash‐flow projects. The cost is that headquarters may pool cash flows from several projects and self‐finance follow‐up investments without having to return to the capital market. Absent any capital market discipline, it is more difficult to force headquarters to make repayments, which tightens financing constraints ex ante. Cross‐sectionally, our model implies that conglomerates should have a lower average productivity than stand‐alone firms.

Richard Schragger, William A. Fischel

In his ambitious new book, William Fischel, a Professor of Economics at Dartmouth College, gives us a new political animal: "The Homevoter." The homevoter is simply a homeowner who votes (p. ix). According to Fischel, she is the key to understanding the political economy of American local government. By implication, she is the key to understanding state and national government as well. Homeowners warrant special attention because "residents who own their own homes have a stake in the outcome of local politics that make them especially attentive to the public policies of local government" (p. ix). That is because local decisions - about how much to spend on schools or trash pick-up, for instance - directly affect home values in ways that most state or national decisions do not. The "homevoter hypothesis" is deceptively straightforward: decentralized, local governments provide a desirable balance of taxes and government services because the homevoter seeks to maintain or increase the value of her single largest asset - the family home (pp. 4-6). The homevoter explains why local governments "work better at providing local services than do larger-area governments" (p. x). This plausible sounding thesis has its roots deep in the decentralizing tradition of public finance theory. The idea that multiple local governments provide government services more efficiently than does a centralized government originated with Charles Tiebout's seminal article, A Pure Theory of Local Expenditures. Tiebout's solution to the problem of how to ensure the proper level of expenditures on public goods was to posit a market in public services. In his model, multiple local governments offer distinctive tax and spending packages, and "consumer-voters" choose to reside in jurisdictions that best fit their preferences, exiting those jurisdictions that do not. The notion that consumers of public goods "vote with their feet" by choosing where to live has become something of an economic maxim.

Ben Levin, John R. Wiens

Education reform is a long-term project, Mr. Levin and Mr. Wiens argue, and the Manitoba Education Agenda for Student Success will not meet the immediate political need to demonstrate bold action. However, by focusing on teaching and learning, respecting all participants, building capacity, and making use of research, it just might achieve the goals we want for all our children. FOR THE LAST 20 years, governments across North America and around the world have been concerned with improving the outcomes of schooling. The pressure to make changes in schools is fueled by national and international test comparisons and driven by the belief that economic competitiveness rests increasingly on people's skills and knowledge. The specifics of education reform vary from setting to setting, shaped by particularities of history, culture, political structures, demography, and other factors. Nonetheless, some common elements are evident across the English-speaking industrialized countries.1 The main strategies have included: * greater specification of curriculum standards and outcomes, with more focus on reading, writing, mathematics, science, and technology; * more assessment of student outcomes and public reporting of the results on a school-by-school basis; * greater opportunity for parents and students to choose the school the student attends; * more pressure on teachers through measures that control their work, limit their pay, test their competence, and so on; * altered finance structures to reward schools that are able to increase academic results or attract more students or both; and * within these policy frames, greater decentralization of managerial responsibility to individual schools. Kappan readers will be familiar with many examples. In the U.S., reforms in Chicago, Kentucky, North Carolina, Texas, and California have been the subject of much discussion, but every state has had some kind of major reform program, and some states have had several different reform programs over the last 10 years. Countries such as England and New Zealand as well as some of the Australian states have gone through some dramatic changes. In Canada, reforms have been particularly extensive in provinces such as Ontario and Alberta. All this reform has produced a great deal of upheaval and much controversy. Many speeches have been made, much improvement has been promised, lots of money has been spent, and many educators have felt disheartened. The results in terms of increased student achievement have been generally disappointing. In reviewing five large-scale change efforts, Ken Leithwood, Doris Jantzi, and Blair Mascall concluded: Most large-scale reforms have not produced gains [in student achievement], however. . . . Furthermore, where data were available on other types of student-related outcomes across the five cases, results were negative. None of the . . . cases of large-scale reform demonstrated evidence of increasing graduation rates, college attendance, or student retention.2 Why have the results of so many reforms been so disappointing? The answer is no great mystery. Reforms have not worked because they have not focused on the things that we know can affect student performance in schools.3 To put it bluntly, improved student outcomes result from appropriate changes in classroom and school practices that are widely accepted and implemented by teachers, seen as meaningful by students, and supported by parents and communities. We have in recent years been learning more and more about each of the elements of this definition. There is growing - though far from complete - agreement on approaches to teaching that are more and less effective. In areas such as reading, writing, mathematics, science, and citizenship we have increasing evidence on the kinds of instructional practices that are most likely to improve students' skills and commitment. …

Mehmet Şişman, Doç. Dr. Selahattin Turan

In the last two decades, educational policy makers and educational leaders have reemphasized the importance of decentralization in education and its critical role in democratization of education and society. Leading scholars in the field state that educational decentralization is a complex process that deals with different dimensions of educational reform efforts and changes about policy making, finance, curriculum and administration of local schools in education. The purpose of this study was to examine the literature concerning decentralization and democratization efforts in education to provide a brief guidelines for government officials, educational policy makers and those who are intended to lead Turkish education and public schools for the twenty first century.