1,608 research outputs found
Query-Answer Causality in Databases: Abductive Diagnosis and View-Updates
Causality has been recently introduced in databases, to model, characterize
and possibly compute causes for query results (answers). Connections between
query causality and consistency-based diagnosis and database repairs (wrt.
integrity constrain violations) have been established in the literature. In
this work we establish connections between query causality and abductive
diagnosis and the view-update problem. The unveiled relationships allow us to
obtain new complexity results for query causality -the main focus of our work-
and also for the two other areas.Comment: To appear in Proc. UAI Causal Inference Workshop, 2015. One example
was fixe
A structural model interpretation of Wright's NESS test
Although understanding causation is an essential part of nearly every problem domain, it has resisted formal treatment in the languages of logic, probability, and even statistics. Autonomous artificially intelligent agents need to be able to reason about cause and effect. One approach is to provide the agent with formal, computational notions of causality that enable the agent to deduce cause and effect relationships from observations. During the 1990s, formal notions of causality were pursued within the AI community by many researchers, notably by Judea Pearl. Pearl developed the formal language of structural models for reasoning about causation. Among the problems he addressed in this formalism was a problem common to both AI and law, the attribution of causal responsibility or actual causation. Pearl and then Halpern and Pearl developed formal definitions of actual causation in the language of structural models. Within the law, the traditional test for attributing causal responsibility is the counterfactual "but-for" test, which asks whether, but for the defendant's wrongful act, the injury complained of would have occurred. This definition conforms to common intuitions regarding causation in most cases, but gives non-intuitive results in more complex situations where two or more potential causes are present. To handle such situations, Richard Wright defined the NESS Test. Pearl claims that the structural language is an appropriate language to capture the intuitions that motivate the NESS test. While Pearl's structural language is adequate to formalize the NESS test, a recent result of Hopkins and Pearl shows that the Halpern and Pearl definition fails to do so, and this thesis develops an alternative structural definition to formalize the NESS test
Research in progress: report on the ICAIL 2017 doctoral consortium
This paper arose out of the 2017 international conference on AI and law doctoral consortium. There were five students who presented their Ph.D. work, and each of them has contributed a section to this paper. The paper offers a view of what topics are currently engaging students, and shows the diversity of their interests and influences
The natural history of bugs: using formal methods to analyse software related failures in space missions
Space missions force engineers to make complex trade-offs between many different constraints including cost, mass, power, functionality and reliability. These constraints create a continual need to innovate. Many advances rely upon software, for instance to control and monitor the next generation âelectron cyclotron resonanceâ ion-drives for deep space missions.Programmers face numerous challenges. It is extremely difficult to conduct valid ground-based tests for the code used in space missions. Abstract models and simulations of satellites can be misleading. These issues are compounded by the use of âband-aidâ software to fix design mistakes and compromises in other aspects of space systems engineering. Programmers must often re-code missions in flight. This introduces considerable risks. It should, therefore, not be a surprise that so many space missions fail to achieve their objectives. The costs of failure are considerable. Small launch vehicles, such as the U.S. Pegasus system, cost around 4 million up to 73 million from the failure of a single uninsured satellite. It is clearly important that we learn as much as possible from those failures that do occur. The following pages examine the roles that formal methods might play in the analysis of software failures in space missions
Ceteris Paribus Laws
Laws of nature take center stage in philosophy of science. Laws are usually believed to stand in a tight conceptual relation to many important key concepts such as causation, explanation, confirmation, determinism, counterfactuals etc. Traditionally, philosophers of science have focused on physical laws, which were taken to be at least true, universal statements that support counterfactual claims. But, although this claim about laws might be true with respect to physics, laws in the special sciences (such as biology, psychology, economics etc.) appear to haveâmaybe not surprisinglyâdifferent features than the laws of physics. Special science lawsâfor instance, the economic law âUnder the condition of perfect competition, an increase of demand of a commodity leads to an increase of price, given that the quantity of the supplied commodity remains constantâ and, in biology, Mendel's Lawsâare usually taken to âhave exceptionsâ, to be ânon-universalâ or âto be ceteris paribus lawsâ. How and whether the laws of physics and the laws of the special sciences differ is one of the crucial questions motivating the debate on ceteris paribus laws. Another major, controversial question concerns the determination of the precise meaning of âceteris paribusâ. Philosophers have attempted to explicate the meaning of ceteris paribus clauses in different ways. The question of meaning is connected to the problem of empirical content, i.e., the question whether ceteris paribus laws have non-trivial and empirically testable content. Since many philosophers have argued that ceteris paribus laws lack empirically testable content, this problem constitutes a major challenge to a theory of ceteris paribus laws
Secondary predication in Russian
The paper makes two contributions to semantic typology of secondary predicates. It provides an explanation of the fact that Russian has no resultative secondary predicates, relating this explanation to the interpretation of secondary predicates in English. And it relates depictive secondary predicates in Russian, which usually occur in the instrumental case, to other uses of the instrumental case in Russian, establishing here, too, a difference to English concerning the scope of the secondary predication phenomenon
Insecurities in employment and occupational careers and their impact on the transition to fatherhood in Western Germany
This paper examines the relationship between work and family among men in Western Germany. We investigate the extent to which a difficult start in working life and insecurities during the working life affect menâs transition to fatherhood, and how this effect is influenced by characteristics of the family of origin and the respondentsâ own relationship history. We use proportional hazards models to analyze data of the third "Familiensurvey" conducted by the German Youth Institute in 2000. In accordance with the spillover hypothesis which assumes that labor market success (or failure) leads to success (or failure) in family behavior as well, we found that under difficult and/or insecure circumstances in their career, men delay their transition to fatherhood. In particular, the delay was related to being unemployed, being self-employed or working part-time. On the other hand, a successful career development increases the propensity to have a child soon after the career step. Contrary to a hypothesis of individualization, the social status and the composition of the family of origin still have an impact on the fertility behavior of men in adulthood. In particular, the transition rate to fatherhood was higher if the man grew up with at least one sibling, while losing a parent through death decreased it. Both employment career and parental home influence the formation of steady relationships, which explains part of their effect on the transition to fatherhood.fertility, Germany, men, professional career, Western Germany
Bell's Theorem and Locally-Mediated Reformulations of Quantum Mechanics
Bell's Theorem rules out many potential reformulations of quantum mechanics,
but within a generalized framework, it does not exclude all "locally-mediated"
models. Such models describe the correlations between entangled particles as
mediated by intermediate parameters which track the particle world-lines and
respect Lorentz covariance. These locally-mediated models require the
relaxation of an arrow-of-time assumption which is typically taken for granted.
Specifically, some of the mediating parameters in these models must
functionally depend on measurement settings in their future, i.e., on input
parameters associated with later times. This option (often called
"retrocausal") has been repeatedly pointed out in the literature, but the
exploration of explicit locally-mediated toy-models capable of describing
specific entanglement phenomena has begun only in the past decade. A brief
survey of such models is included here. These models provide a continuous and
consistent description of events associated with spacetime locations, with
aspects that are solved "all-at-once" rather than unfolding from the past to
the future. The tension between quantum mechanics and relativity which is
usually associated with Bell's Theorem does not occur here. Unlike conventional
quantum models, the number of parameters needed to specify the state of a
system does not grow exponentially with the number of entangled particles. The
promise of generalizing such models to account for all quantum phenomena is
identified as a grand challenge.Comment: 61 pages, 2 figures; accepted for publication by Rev. Mod. Phy
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