18,519 research outputs found
Co-occurrence Vectors from Corpora vs. Distance Vectors from Dictionaries
A comparison was made of vectors derived by using ordinary co-occurrence
statistics from large text corpora and of vectors derived by measuring the
inter-word distances in dictionary definitions. The precision of word sense
disambiguation by using co-occurrence vectors from the 1987 Wall Street Journal
(20M total words) was higher than that by using distance vectors from the
Collins English Dictionary (60K head words + 1.6M definition words). However,
other experimental results suggest that distance vectors contain some different
semantic information from co-occurrence vectors.Comment: 6 pages, appeared in the Proc. of COLING94 (pp. 304-309)
Space-irrelevant scaling law for fish school sizes
Universal scaling in the power-law size distribution of pelagic fish schools
is established. The power-law exponent of size distributions is extracted
through the data collapse. The distribution depends on the school size only
through the ratio of the size to the expected size of the schools an arbitrary
individual engages in. This expected size is linear in the ratio of the spatial
population density of fish to the breakup rate of school. By means of extensive
numerical simulations, it is verified that the law is completely independent of
the dimension of the space in which the fish move. Besides the scaling analysis
on school size distributions, the integrity of schools over extended periods of
time is discussed.Comment: 23 pages, 12 figures, to appear in J. Theor. Bio
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