  In this paper we present statistical analysis of English texts from
Wikipedia. We try to address the issue of language complexity empirically by
comparing the simple English Wikipedia (Simple) to comparable samples of the
main English Wikipedia (Main). Simple is supposed to use a more simplified
language with a limited vocabulary, and editors are explicitly requested to
follow this guideline, yet in practice the vocabulary richness of both samples
are at the same level. Detailed analysis of longer units (n-grams of words and
part of speech tags) shows that the language of Simple is less complex than
that of Main primarily due to the use of shorter sentences, as opposed to
drastically simplified syntax or vocabulary. Comparing the two language
varieties by the Gunning readability index supports this conclusion. We also
report on the topical dependence of language complexity, e.g. that the language
is more advanced in conceptual articles compared to person-based (biographical)
and object-based articles. Finally, we investigate the relation between
conflict and language complexity by analyzing the content of the talk pages
associated to controversial and peacefully developing articles, concluding that
controversy has the effect of reducing language complexity.
