1,476 research outputs found

    Resolvable designs with large blocks

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    Resolvable designs with two blocks per replicate are studied from an optimality perspective. Because in practice the number of replicates is typically less than the number of treatments, arguments can be based on the dual of the information matrix and consequently given in terms of block concurrences. Equalizing block concurrences for given block sizes is often, but not always, the best strategy. Sufficient conditions are established for various strong optimalities and a detailed study of E-optimality is offered, including a characterization of the E-optimal class. Optimal designs are found to correspond to balanced arrays and an affine-like generalization.Comment: Published at http://dx.doi.org/10.1214/009053606000001253 in the Annals of Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical Statistics (http://www.imstat.org

    Completeness and Categoricty, Part II: 20th Century Metalogic to 21st Century Semantics

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    This paper is the second in a two-part series in which we discuss several notions of completeness for systems of mathematical axioms, with special focus on their interrelations and historical origins in the development of the axiomatic method. We argue that, both from historical and logical points of view, higher-order logic is an appropriate framework for considering such notions, and we consider some open questions in higher-order axiomatics. In addition, we indicate how one can fruitfully extend the usual set-theoretic semantics so as to shed new light on the relevant strengths and limits of higher-order logic

    Taxpayer Search for Information: Implications for Rational Attention

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    We examine novel data on searches for capital-gains-tax-related information to determine when and how taxpayers acquire information. We find strong seasonal increases in information search around tax filing deadlines, suggesting that taxpayers seek information to comply with tax law. Positive correlations between stock market activity and information search and year-end spikes in information search on capital losses suggest that taxpayers seek information for tax planning purposes. Policy changes and news events cause noteworthy information search. Overall, these data suggest that taxpayers are not always fully informed, but that rational attention and exogenous shocks to tax salience drive taxpayer information search.http://deepblue.lib.umich.edu/bitstream/2027.42/99756/1/1198_Slemrod.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/99756/4/1198_Slemrod_sept13.pd

    Logic in the 1930s: type theory and model theory

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    Teaching Children to use a Context-plus-Phonics Strategy

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    The main purpose of this article is to describe in detail a procedure which teaches children to integrate two word identification strategies, ose of context and of phonics. A study was conducted which tested the effectiveness of this integrative strategy, and a secondary purpose of this article is to present the results of the study

    A Bell-type test of energy-time entangled qutrits

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    We have performed a Bell-type test for energy-time entangled qutrits. A method of inferring the Bell violation in terms of an associated interference visibility is derived. Using this scheme we obtained a Bell value of 2.784±0.0232.784 \pm 0.023, representing a violation of 34σ34 \sigma above the limit for local variables. The scheme has been developed for use at telecom wavelengths and using proven long distance quantum communication architecture to optimize the utility of this high dimensional entanglement resource.Comment: replaced lost acknowledement

    Who Sold During the Crash of 2008-9? Evidence from Tax-Return Data on Daily Sales of Stock

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    We examine individual stock sales from 2008 to 2009 using population tax return data. The share of sales by the top 0.1 percent of income recipients and other top income groups rose sharply following the Lehman Brothers bankruptcy and remained elevated throughout the financial crisis. Sales by top income and older age groups were relatively more responsive to increased stock market volatility. Volatility-driven sales were not concentrated in any one sector, but mutual fund sales responded more strongly to increased volatility than stock sales. Additional analysis suggests that gross sales in tax return data are informative about unobserved net sales.http://deepblue.lib.umich.edu/bitstream/2027.42/118067/1/1316_Nagel.pd

    Analysis of alcohol dependence phenotype in the COGA families using covariates to detect linkage

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    Linkage analysis methods that incorporate etiological heterogeneity of complex diseases are likely to demonstrate greater power than traditional linkage analysis methods. Several such methods use covariates to discriminate between linked and unlinked pedigrees with respect to a certain disease locus. Here we apply several such methods including two mixture models, ordered subset analysis, and a conditional logistic model to genome scan data on the DSM-IV alcohol dependence phenotype on the Collaborative Studies on Genetics of Alcoholism families, and compare the results to traditional nonparametric linkage analysis. In general, there was little agreement among the various covariate-based linkage statistics. Linkage signals with empirical p-values less than 0.001 were detected on chromosomes 3, 4, 7, 10, and 12, with the highest peak occurring at the GABRB1 gene using the ecb21 covariate

    Completeness and Categoricty, Part II: 20th Century Metalogic to 21st Century Semantics

    Get PDF
    This paper is the second in a two-part series in which we discuss several notions of completeness for systems of mathematical axioms, with special focus on their interrelations and historical origins in the development of the axiomatic method. We argue that, both from historical and logical points of view, higher-order logic is an appropriate framework for considering such notions, and we consider some open questions in higher-order axiomatics. In addition, we indicate how one can fruitfully extend the usual set-theoretic semantics so as to shed new light on the relevant strengths and limits of higher-order logic

    Imperfect Detectors in Linear Optical Quantum Computers

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    We discuss the effects of imperfect photon detectors suffering from loss and noise on the reliability of linear optical quantum computers. We show that for a given detector efficiency, there is a maximum achievable success probability, and that increasing the number of ancillary photons and detectors used for one controlled sign flip gate beyond a critical point will decrease the probability that the computer will function correctly. We have also performed simulations of some small logic gates and estimate the efficiency and noise levels required for the linear optical quantum computer to function properly.Comment: 13 pages, 5 figure
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