Results 221 to 230 of about 1,562,553 (261)

An experiment in index term frequency

Journal of the American Society for Information Science, 1972
AbstractThis paper presents an experimental study of index‐term frequency as a factor in retrieval performance. The frequency of an index term, or its “breadth” as it is called here, is the number of postings made to the term in a given collection. The question is asked: Of index terms assigned to documents, which function most effectively in retrieval,
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Analysis in Terms of Frequencies of Differences

Psychometrika, 1947
A technique of analysis utilizing frequencies of differences is described and applied to a hypothetical experiment involving two methods of instruction. A nomograph is provided for computing the chi-square values applicable to the method.
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Estimating term domain relevance through term frequency, disjoint corpora frequency - tf-dcf

Knowledge-Based Systems, 2016
This paper proposes a new relevance index for terms extracted from domain corpora. We call it term frequency, disjoint corpora frequency (tf-dcf), and it is based on the absolute frequency of each term tempered by its frequency in other (contrasting) corpora.
Lucelene Lopes, Paulo Fernandes 0001, Renata Vieira   +2 more
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Nonlinear transformation of term frequencies for term weighting in text categorization

Engineering Applications of Artificial Intelligence, 2012
In automatic text categorization, the influence of features on the decision is set by the term weights which are conventionally computed as the product of term frequency and collection frequency factors. The raw form of term frequencies or their logarithmic forms are generally used as the term frequency factor whereas the leading collection frequency ...
Erenel, Zafer, Altincay, Hakan
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Short-Term Frequency Stability of Precision Oscillators and Frequency Generators

Bell System Technical Journal, 1971
We present in this paper two definitions of short-term frequency stability: (i) time domain, the expected value of the variance of the fractional frequency fluctuations from nominal frequency, y 3(N, T, τ)=, in which N is the number of samples, T is the averaging time plus the dead time between samples, and τ is the averaging time; and (ii) frequency ...
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Term Impacts as Normalized Term Frequencies for BM25 Similarity Scoring

2008
The BM25 similarity computation has been shown to provide effective document retrieval. In operational terms, the formulae which form the basis for BM25 employ both term frequency and document length normalization. This paper considers an alternative form of normalization using document-centric impacts, and shows that the new normalization ...
Vo Ngoc Anh, Raymond Wan 0001, Alistair Moffat   +2 more
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Term distance, frequency and collocations

2021
Abstract In this paper I study two co-occurrence measures, local to a particular corpus, for constructing collocations or relevance relations between words or terms. One is a distance measure, while the other uses different co-occurrence windows, one contained in the other. Both are discussed with respect to the common method of comparing co-occurrence
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A study of parameter tuning for term frequency normalization

Proceedings of the twelfth international conference on Information and knowledge management, 2003
Most current term frequency normalization approaches for information retrieval involve the use of parameters. The tuning of these parameters has an important impact on the overall performance of the information retrieval system. Indeed, a small variation in the involved parameter(s) could lead to an important variation in the precision/recall values ...
Ben He, Iadh Ounis
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Frequency domain Volterra filters in terms of distributions

IEEE Signal Processing Letters, 1994
The Fourier transform of the output of a Volterra filter is given in terms of Schwartz distributions. This theory is developed in order to handle input signals that do not possess a Fourier transform in the usual sense. To illustrate this, the authors apply the result to the case of a sinusoidal input and to the case of a sampled and periodized signal.
Pierre-Olivier Amblard, Eric Moisan
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On the use of the term ‘frequency’ in applied behavior analysis

Journal of Applied Behavior Analysis, 2018
There exists a terminological problem in applied behavior analysis: the term frequency has been used as a synonym for both rate (the number of responses per time) and count (the number of responses). To guide decisions about the use and meaning of frequency, we surveyed the usage of frequency in contemporary behavior‐analytic journals and textbooks and
James E, Carr, Melissa R, Nosik, Molli M, Luke   +2 more
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