A Paradox of Evidential Equivalence

Our evidence can be about different subject matters. In fact, necessarily equivalent pieces of evidence can be about different subject matters. Does the hyperintensionality of ‘aboutness’ engender any hyperintensionality at the level of rational credence? In this paper, I present a case which seems to suggest that the answer is ‘yes’. In particular, I argue that our intuitive notions of independent evidence and inadmissible evidence are sensitive to aboutness in a hyperintensional way. We are thus left with a paradox. While there is strong reason to think that rational credence cannot make such hyperintensional distinctions, our intuitive judgements about certain cases seem to demand that it does

Authoritatively Normative Concepts

This paper offers an analysis of the authoritatively normative concept PRACTICAL OUGHT that appeals to the constitutive norms for the activity of non-arbitrary selection. I argue that this analysis permits an attractive and substantive explanation of what the distinctive normative authority of this concept amounts to. I contrast my account with more familiar constitutivist theories, and briefly show how it answers ‘schmagency’-style objections to constitutivist explanations of normativity. Finally, I explain how the account offered here can be used to help realists, error theorist, and fictionalists address central challenges to their views

Causes and Explanations: A Structural-Model Approach, Part I: Causes

We propose a new definition of actual cause, using structural equations to model counterfactuals. We show that the definition yields a plausible and elegant account of causation that handles well examples which have caused problems for other definitions and resolves major difficulties in the traditional account.Comment: Part II of the paper (on Explanation) is also on the arxiv. Previously the two parts were submitted as one paper. To appear in the British Journal for the Philosophy of Scienc

Fast self-stabilizing byzantine tolerant digital clock synchronization

Consider a distributed network in which up to a third of the nodes may be Byzantine, and in which the non-faulty nodes may be subject to transient faults that alter their memory in an arbitrary fashion. Within the context of this model, we are interested in the digital clock synchronization problem; which consists of agreeing on bounded integer counters, and increasing these counters regularly. It has been postulated in the past that synchronization cannot be solved in a Byzantine tolerant and self-stabilizing manner. The first solution to this problem had an expected exponential convergence time. Later, a deterministic solution was published with linear convergence time, which is optimal for deterministic solutions. In the current paper we achieve an expected constant convergence time. We thus obtain the optimal probabilistic solution, both in terms of convergence time and in terms of resilience to Byzantine adversaries

Leakage-resilient coin tossing

Proceedings 25th International Symposium, DISC 2011, Rome, Italy, September 20-22, 2011.The ability to collectively toss a common coin among n parties in the presence of faults is an important primitive in the arsenal of randomized distributed protocols. In the case of dishonest majority, it was shown to be impossible to achieve less than 1 r bias in O(r) rounds (Cleve STOC ’86). In the case of honest majority, in contrast, unconditionally secure O(1)-round protocols for generating common unbiased coins follow from general completeness theorems on multi-party secure protocols in the secure channels model (e.g., BGW, CCD STOC ’88). However, in the O(1)-round protocols with honest majority, parties generate and hold secret values which are assumed to be perfectly hidden from malicious parties: an assumption which is crucial to proving the resulting common coin is unbiased. This assumption unfortunately does not seem to hold in practice, as attackers can launch side-channel attacks on the local state of honest parties and leak information on their secrets. In this work, we present an O(1)-round protocol for collectively generating an unbiased common coin, in the presence of leakage on the local state of the honest parties. We tolerate t ≤ ( 1 3 − )n computationallyunbounded Byzantine faults and in addition a Ω(1)-fraction leakage on each (honest) party’s secret state. Our results hold in the memory leakage model (of Akavia, Goldwasser, Vaikuntanathan ’08) adapted to the distributed setting. Additional contributions of our work are the tools we introduce to achieve the collective coin toss: a procedure for disjoint committee election, and leakage-resilient verifiable secret sharing.National Defense Science and Engineering Graduate FellowshipNational Science Foundation (U.S.) (CCF-1018064

The Challenge of High Unemployment

It is argued that policymakers, macroeconomists and microeconomists should all take high unemployment more seriously. The shortcomings of existing theories of unemployment are discussed, and a new definition of involuntary unemployment is proposed. A model is sketched in which falling aggregate demand leads to "Keynesian" unemployment because labor is heterogeneous and relative wages matter. Microeconomic theory is criticized for assuming away unemployment and, in the process, radically changing the answers to some basic questions in trade theory and public finance. Finally, some speculative explanations are offered for the low unemployment now found in states like New Jersey and Massachusetts.

Electronically Manufactured Law

This Article seeks to strengthen the case for the academy and the legal profession to pay heed to the consequences of the shift to electronic research, primarily by employing cognitive psychology to guide predictions about the impacts of the shift and, thereby, address a perceived credibility gap. This credibility gap arises from the difficulty and imprecision in postulating how changes in the research process translate into changes in researcher behavior and research outcomes. Applying principles of cognitive psychology to compare the print and electronic research processes provides an analytical basis for connecting changes in the research process with changes in researcher behavior and research outcomes. Cognitive psychology generates two specific predictions about how electronic research will change the law. First, electronic research will lead to increased diversity in framing -- divergence in the selection of the legal theory or theories through which to conceptualize facts, arguments, and cases. Second, electronic research will lead to more tilting at windmills -- the advancement of marginal cases, theories, and arguments. The Article explores how an increase in diversity in framing and tilting at windmills could affect the legal profession and the law. For example, in an adversarial system, judicial options for case resolution are largely defined and constrained by the theories proffered by counsel. Diversity in framing could expand judicial authority by providing judges with a wider variety of options for dispute resolution. This underlines the way in which counsel serve as gatekeepers by exercising judgment about which cases and theories have sufficient merit to warrant pursuit. Increased tilting at windmills may require recalibration of the existing limits placed on lawyers in their role as gatekeepers. Recalibration may be necessary to prevent the dedication of client and judicial resources to lost causes spurred by lapses in judgment related to electronic research and to allow attorneys to advance, without fear of sanctions, thoughtful arguments designed to push doctrinal boundaries. Specifically, Part II reviews existing legal theory, scholarship, and data that suggest that the shift to electronic research will likely have broad-ranging impacts. Part III compares print and electronic research and discusses three particularly salient changes in research process: (1) electronic researchers are not guided by the key system to the same extent as print researchers when identifying relevant theories, principles, and cases; (2) electronic researchers do not encounter and interpret individual cases through the lens of key system information to the same extent as print researchers; and (3) electronic researchers are exposed to more and different case texts than print researchers. Part IV uses principles of cognitive psychology to examine these process differences and predict two major non-process consequences of the shift to electronic research: increased diversity in framing and tilting at windmills. Part V concludes by assessing the broader significance of these hypothesized consequences