When both the variance and the N are unequal in a two-group design, the probability of a Type I error shifts from the nominal 5% error rate. The probability is too liberal when the small cell has the larger variance a...
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When both the variance and the N are unequal in a two-group design, the probability of a Type I error shifts from the nominal 5% error rate. The probability is too liberal when the small cell has the larger variance and too conservative when the large cell has the larger variance. We present an algorithm to circumvent the problem when the smaller group has the larger variance and show, by simulation, that the algorithm brings the error rate back to the nominal value without sacrificing the ability to detect true effects.
Computational models of lexical semantics, such as latent semantic analysis, can automatically generate semantic similarity measures between words from statistical redundancies in text. These measures are useful for e...
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Computational models of lexical semantics, such as latent semantic analysis, can automatically generate semantic similarity measures between words from statistical redundancies in text. These measures are useful for experimental stimulus selection and for evaluating a model's cognitive plausibility as a mechanism that people might use to organize meaning in memory. Although humans are exposed to enormous quantities of speech, practical constraints limit the amount of data that many current computational models can learn from. We follow up on previous work evaluating a simple metric of pointwise mutual information. Controlling for confounds in previous work, we demonstrate that this metric benefits from training on extremely large amounts of data and correlates more closely with human semantic similarity ratings than do publicly available implementations of several more complex models. We also present a simple tool for building simple and scalable models from large corpora quickly and efficiently.
A brief description is given of the implementation technique for the replacement rule of the AMBIT programming language. The algorithm for the “AMBIT scan” and an example of its application are given. The algorithm ...
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This article focuses on the use of data abstraction for the expression of algorithms and relevant data structures. Research in the language and database areas have common themes. Both areas attempt to develop more mea...
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This article focuses on the use of data abstraction for the expression of algorithms and relevant data structures. Research in the language and database areas have common themes. Both areas attempt to develop more meaningful levels of discourse, to suppress reliance on the machine representation of data, and to hide the physical properties of the implementation from the logical properties that the user sees. The principal goal of a programming language designer is to create a general purpose tool for the expression of algorithms and relevant data structures. The language should include features that will allow algorithms to be expressed in problem oriented terms. Benefits of such an approach are clearer programs that are easier to verify and maintain. It is also easier to change various representation decisions, since encapsulating data representations in modules guarantees that operators cannot become dependent on any particular representation. Data abstractions are considered local to the program and are chosen by the programmer or system designer. Interrelationships among data abstractions and mechanisms for dealing with complex interrelated files are not yet in the mainstream of this research.
Background. Augmentation index (AIx) is traditionally obtained from pressure waveforms via arterial applanation tonometry. We sought to evaluate the association between AIx obtained from peripheral arterial tonometry ...
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Background. Augmentation index (AIx) is traditionally obtained from pressure waveforms via arterial applanation tonometry. We sought to evaluate the association between AIx obtained from peripheral arterial tonometry (PAT) with cardiovascular risk factors (CRF) and coronary artery disease (CAD). Methods. 186 patients were enrolled in the study. The presence or absence of CRFs and CAD was assessed in each subject. AIx was calculated by an automated algorithm averaging pulse wave amplitude data obtained via PAT. Central blood pressures were assessed in a subset of patients undergoing clinically indicated cardiac catheterization. Results. An association was observed between AIx and age, heart rate, systolic blood pressure, mean arterial pressure, pulse pressure, body weight and body mass index. AIx was significantly lower in patients with <3 CRFs compared to those with >5 CRFs (P - .02). CAD+ patients had significantly higher AIx compared to CAD-patients (P = .008). Area under the ROC curve was 0.604 (P < .01). In patients undergoing cardiac catheterization, after adjusting for age, height and heart rate, AIx was a significant predictor of aortic systolic and pulse pressures (P < .05) Conclusion. AIx derived from PAT correlates with cardiac risk factors and CAD. It may be a useful measure of assessing overall risk for coronary artery disease.
From the Publisher: Here's a cutting-edge resource that brings you up-to-date with all the recent advances in computational electromagnetics. You get the most-current information available on the multilevel fast m...
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ISBN:
(纸本)1580531520
From the Publisher: Here's a cutting-edge resource that brings you up-to-date with all the recent advances in computational electromagnetics. You get the most-current information available on the multilevel fast multipole algorithm in both the time and frequency domains, as well as the latest developments in fast algorithms for low frequencies and specialized structures, such as the planar and layered media. These algorithms solve large electromagnetics problems with shorter turn around time, using less computer memory. Complex problems that once required a supercomputer to solve, can now be solved on a workstation or personal computer with the innovative methods taught in this resource. The book introduces you to new advances in the perfectly matched layer absorbing boundary conditions, and offers you a thorough understanding of error analysis of numerical methods, fast-forward and inverse solvers for inverse problems, hybridization in computational electromagnetics, and asymptotic waveform evaluation.
An automated system that analyses medication orders and diagnostic claims can detect and prevent potential medication errors due to look-alike/sound-alike (LASA) drug names, say US researchers. The researchers extract...
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An automated system that analyses medication orders and diagnostic claims can detect and prevent potential medication errors due to look-alike/sound-alike (LASA) drug names, say US researchers. The researchers extracted medication order data for a 10-year period from the electronic health records in the University of Illinois Hospital and Health Services...
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