2012 Summer Symposium Program - Middlebury College

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Patrick Adelstein ‘14
Major: CSCI, MATH
Bicentennial Fund
Edward Pendergast ‘13
Major: CSCI
Bicentennial Fund
David Kauchak
Assistant Professor of Computer
Science
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Meg Anderson ‘14
Major: BIOL
VT EPSCoR/RACC
Sallie Sheldon
Professor of Biology
Middlebury Summer Research Symposium 2012
Does Context Matter in Lexical Simplification?
Patrick Adelstein, Edward Pendergast, and David Kauchak
Department of Computer Science, Middlebury College, Middlebury VT 05753
Lexical Simplification is the task of replacing a target word or phrase in a sentence
to make the sentence simpler. Lexical simplification is a sub-problem of the full
text simplification problem which can benefit children, second language learners,
and people with cognitive disabilities. In this paper we investigate whether the
textual context surrounding the word to be replaced is important in identifying and
selecting substitutions. Starting with a corpus of sentence-aligned English Wikipedia
and Simple English Wikipedia data we generated lexical simplification examples.
These examples consist of a sentence, a target word to replace, and a list of candidate
substitutes solicited from users on Amazon’s Mechanical Turk service. We compare
data collected both with and without the sentence context and utilize a variety of
metrics including frequency, entropy, and similarity of the collected substitutes. We
find that for some words context does matter for the simplification task, however not
for all words.
Substrate effect on periphyton composition and
abundance in the New Haven River
Meg Anderson and Sallie Sheldon
Department of Biology, Middlebury College, Middlebury VT 05753
This study focused on the relationship between rock size and the algae covering the
rock surface (periphyton). Glass microscope slides were installed in three different
substrate types (sand/gravel, coarse gravel and cobble/boulder) in a small section of
the New Haven River in Bristol, Vermont. Slides were collected over the course
of three weeks to assess species composition, and after three and a half weeks,
periphyton on the cement blocks was dried and weighed. Species composition was
similar between substrate types, and periphyton density increased over time in the
stream. Periphyton abundance was directly related to substrate size with very little
periphyton accruing on cement blocks in sand/gravel. The results from this study
suggest that while the composition of periphyton in streams may not be related
to substrate type, the abundance of periphyton is affected. Further research using
cement blocks and natural substrates will lead to better understanding of which
abiotic factors have the greatest effect on periphyton in streams.