787 research outputs found
Predictive Probabilities In Employee Drug-Testing
Substance abuse in the U.S. has been estimated to cost $99 billion annually through lower productivity. Yet the authors urge caution in attempting to reduce these costs and health and safety Risks. In doing so, they cite commonly high frequencies of false negatives and false positives in employee drug tests - the latter having the potential to do great injustice to many drug-free employees
Performance Indicator Analysis of Proficiency Criteria in the Drug-Testing-Laboratory Certification Process of the DHHS
The authors highlight and propose remedies for problems in the proficiency criteria used in certifying laboratories for drug testing federal employees in the United States
Book Review
Review of the following: HELENA CHMURA KRAEMER, EVALUATING MEDICAL TESTS: OBJECTIVE AND QUANTITATIVE GUIDELINES. (Sage Publications 1992). [295 pp.] Foreword A. John Rush, M.D. Acknowledgments, index, list of statistical notations, preface, references, and about the author. ISBN 0- 8039-4611-2 (cloth); 0-8039-4612-0 (paper). [Cloth 22.50. 2455 Teller Road, Newbury Park CA 91320.
Ambiguity and legal compliance
Research Summary: This study examines the independent and joint effect of ambiguity and perceived certainty of apprehension on law-breaking decision-making. Data come from a survey of experienced drivers (N = 1147) who viewed videos depicting a car speeding on an interstate highway under experimentally manipulated circumstances. The sampled drivers were generally ambiguity averse, opting to reduce speeding as ambiguity about the perceived certainty of apprehension increased. However, perceived ambiguity interacted with perceived certainty such that increases in ambiguity increased the deterrent effect of ambiguity for low certainty probabilities and decreased the effect for high probabilities. Policy Implications : Ambiguity may serve as a valuable tool for increasing the efficacy of crime-prevention strategies, especially for crimes with naturally low levels of risk. However, researchers should think carefully about the effects of ambiguity when analyzing the efficacy of certainty-based policies because the injection of ambiguity can both increase and decrease legal compliance. Also, discussed are the implications for a key function of policing —traffic safety. <br
Small Business Drug-Testing Strategy: Implications of Pre-Employment Testing
This paper identifies problems in drug testing accuracy that may arise in small business environments in which job applicants are subjected to drug tests, and suggests a method for dealing with the problems. Relevant concepts of drug-test accuracy are reviewed These concepts are incorporated in Bayesian analyses of data from specific workplace-applicant populations, and accuracy levels to be expected in testing of applicants in such workplaces are identified The conclusion of this analysis is that seemingly accurate tests for abused drugs can be inaccurate to a disturbingly high degree, particularly under circumstances likely to be present in many small business drug-testing programs. A method by which these inaccuracies can be avoided is suggested
Sanction risk perceptions, coherence, and deterrence
Research from environmental criminology, policing, and related literatures consistently finds that objective conditions related to risk of apprehension affect crime. The mechanism underlying this relationship is not explicitly tested; instead, perceptual deterrence is assumed. In this analysis we explicitly investigate that mechanism. This test is not straightforward, however, as some research shows that risk perceptions are susceptible to various cognitive biases and framing effects. Thus, we advance a framework of sanction risk perception that combines individual and contextual determinants. Specifically, we investigate whether contextual factors materially influence risk perceptions and in turn intentions to offend after accounting for the influence of individual‐specific determinants. Our data come from an experimental survey on speeding (N = 1,919). Respondents viewed videos from the driver's perspective of a sedan speeding on a highway and provided estimates of sanction risk, safety perceptions, and behavioral intentions. Although sanction risk and safety perceptions for speeding varied widely across respondents, they remained grounded in the objective conditions of the experimental videos. In turn, citizen perceptions of apprehension risk were comparable with risk estimates elicited from state troopers after viewing the same videos. The results suggest deterrence and safety considerations are important contributing factors that help shape intentions to transgress
Compressibility of Mixed-State Signals
We present a formula that determines the optimal number of qubits per message
that allows asymptotically faithful compression of the quantum information
carried by an ensemble of mixed states. The set of mixed states determines a
decomposition of the Hilbert space into the redundant part and the irreducible
part. After removing the redundancy, the optimal compression rate is shown to
be given by the von Neumann entropy of the reduced ensemble.Comment: 7 pages, no figur
The chain rule implies Tsirelson's bound: an approach from generalized mutual information
In order to analyze an information theoretical derivation of Tsirelson's
bound based on information causality, we introduce a generalized mutual
information (GMI), defined as the optimal coding rate of a channel with
classical inputs and general probabilistic outputs. In the case where the
outputs are quantum, the GMI coincides with the quantum mutual information. In
general, the GMI does not necessarily satisfy the chain rule. We prove that
Tsirelson's bound can be derived by imposing the chain rule on the GMI. We
formulate a principle, which we call the no-supersignalling condition, which
states that the assistance of nonlocal correlations does not increase the
capability of classical communication. We prove that this condition is
equivalent to the no-signalling condition. As a result, we show that
Tsirelson's bound is implied by the nonpositivity of the quantitative
difference between information causality and no-supersignalling.Comment: 23 pages, 8 figures, Added Section 2 and Appendix B, result
unchanged, Added reference
Indeterminate-length quantum coding
The quantum analogues of classical variable-length codes are
indeterminate-length quantum codes, in which codewords may exist in
superpositions of different lengths. This paper explores some of their
properties. The length observable for such codes is governed by a quantum
version of the Kraft-McMillan inequality. Indeterminate-length quantum codes
also provide an alternate approach to quantum data compression.Comment: 32 page
Distinguishing multi-partite states by local measurements
We analyze the distinguishability norm on the states of a multi-partite
system, defined by local measurements. Concretely, we show that the norm
associated to a tensor product of sufficiently symmetric measurements is
essentially equivalent to a multi-partite generalisation of the non-commutative
2-norm (aka Hilbert-Schmidt norm): in comparing the two, the constants of
domination depend only on the number of parties but not on the Hilbert spaces
dimensions.
We discuss implications of this result on the corresponding norms for the
class of all measurements implementable by local operations and classical
communication (LOCC), and in particular on the leading order optimality of
multi-party data hiding schemes.Comment: 18 pages, 6 figures, 1 unreferenced referenc
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