Stylistics and Stylometry

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Stylistics and Stylometry

• CSC 5930 Machine Translation
• Fall 2012 Dr. Tom Way

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What is style?

• Term not much loved by linguists
• Too vague
• Has connotations in similar fields (style
  good style, a value judgment)
• Many books/articles make reference to etymology
  of the word (Lat. stilus pen), so it follows
  that style is mainly about written language
• Various definitions, some very close to things
  already seen (especially register)
• Two main aspects widely supposed
• style is choice
• style is described by reference to something else

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Style as choice

• For any intended meaning there are a range of
  alternative ways of expressing that meaning
• Different choices express nuances
• of meaning
• of other things (style?) eg buy vs purchase
• Example
• Visitors are respectfully informed that the coin
  required for the meter is a quarter no other
  coin is acceptable
• Quarters only
• Propositional meaning is the same difference in
  expression conveys something else

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Style as choice (2)

• Style is a choice, but often the choice is
  somewhat predetermined
• For example a choice between appropriate and
  inappropriate style
• So perhaps style does not connote good or bad
  but merely the way in which the author expresses
  or conveys things

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Style and the norm

• Some writers define style as
• individual characteristics of a text
• total sum of deviations from a norm
• But what is the norm?
• Is there some form of the language that is
  neutral as regards style?
• Note also that the norm shifts for example, many
  works are written in the vernacular of their time
• Literary stylistics focuses on the exceptional

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Style and the norm (2)

• Even if there is no norm, we can describe style
  comparatively
• Stylistics mainly involves comparing and
  contrasting texts
• and associating linguistic variance with
  contextual explanation
• Some authors see style as being what is added to
  the text

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Stylistic analysis

• Gulf between literary vs. linguistic stylistics
• Literary criticism focuses on effect on the
  reader, intended or otherwise, so largely
  intuitive and subjective
• Linguistic stylistics looks for characterisations
  of style (including literary style) in terms of
  linguistic phenomena at the various levels of
  linguistic description

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Stylistic analysis (2)

• Inventory of linguistic devices and their effect
• usually in a contrastive way
• in contrast with other writers in a similar genre
• in contrast with other genres
• Linguistic devices described in terms of the
  usual linguistic levels of description
  phonology, morphology, lexis, grammar, etc.
• Effects can be directly expressive, or
  indirectly, by association
• example onomatopoeia vs. alliteration as a
  phonological device

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Stylistic analysis (3)

• Informally identify stylistic features felt to be
  significant
• Devise a method of analysis which facilitates
  comparison between usages
• Identify the stylistic function of the features
  so identified

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Types of features

• Invariable features due to the individual or
  the time usually of little interest
• Discourse features
• medium ( Hallidays mode), what features
  distinguish written language from spoken language
• participation eg monologue vs dialogue
• Province ( field) lexis and syntax
• Status ( tenor) features relating to relative
  social standing of writer/speaker and
  reader/listener
• Modality ( text type) eg message delivered as a
  letter, postcard, text message, email, etc
• Singularity deliberate occasional idiosyncracies

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Method and function

• Methods and features determine each other
• you can only measure features that you can
  extract
• simple counting features are easy to extract
• more complex features can be extracted thanks to
  NLP techniques of corpus annotation (tagging,
  parsing, etc)
• Describing the function of observed differences
• could be based on intuition
• or (see later) partially automated (factor
  analysis)

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What to count

• Simple things may characterize different styles
• average sentence length
• average word length
• typetoken ratio (vocabulary richness)
• number of types number of different words
• number of tokens total number of words
• vocabulary growth (homogeneity of text)
• number of new types in 1st, 2nd, , nth 1000
  words
• in rich varied text, number will climb steadily
• Especially when used comparatively

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What to count (2)

• More complex analyses can give a more interesting
  picture
• specific syntactic structures
• degree of modification in NPs
• types of verbs (eg verbs of persuasion, speech
  verbs, action verbs, descriptive verbs)
• distribution of pronouns (1st/2nd/3rd person)
• etc (anything you can think of)
• Quite sophisticated mathematical techniques can
  give an overall picture
• eg factor analysis identifies from a (big) range
  of variables which ones best identify/characterize
  differences

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Normalization and significance

• Always important to compare like with like
• It is usual when counting things to normalize
  over the length of the text
• If one text is longer than the other, of course
  you would expect higher frequencies of everything
• Issue of statistical significance
• Small differences may not really tell you
  anything
• Various measures can confirm whether difference
  is statistically significant or due to random
  fluctuation

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How to count

• How to recognize paragraph breaks?
• How to recognize sentence breaks?
• Headlines dont end in a full stop
• Not all sentences end in a full stop
• Not all full stops are sentence ending
  (abbreviations)
• How to count words
• Hyphenated words, contractions e.g. dont
• How to measure word-length/complexity
• length only roughly corresponds to complexity
• number of characters vs. number of syllables
• counting syllables implies either a dictionary or
  an algorithm

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More sophisticated counting

• Tagging and parsing allows you to look at
  grammatical and lexical issues
• Use of particular POSs (conjunctions, pronouns,
  auxiliaries, modals)
• Use of particular features (tenses, )
• Use of particular constructions (passives,
  interrogatives)

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Quantifying register differences

• Much work based on corpora trying to quantify and
  characterize register differences
• Work pioneered by Douglas Biber
• Simple counts like the ones suggested
• Also, more complex computations

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Example
From D. Biber, S. Conrad R. Reppen, Corpus
Linguistics Investigating Language Structure and
Use, Cambriufge University Press, 1998. Ch 5 the
study of discourse characteristics
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Multidimensional analysis

• Collect a huge range of measures of a wide
  variety
• some simple word counts
• syntactic features
• classes and subclasses of N,V,Adj,Avd
• Factor analysis

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150 features in all
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Factor analysis

• Statistical method to take large number of
  apparently random variables and group them
  together into factors
• Factors will be groups of (ve and ve) features
• Linguist might then try to characterize the
  factors in terms of some psycholinguistic feature

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Example

• Biber took two Google classifications of text
  types Home and Science
• Harvested 1500 webpages in each category (3.74m
  words)
• originally got 2500 webpages, but some were not
  suitable

http//jan.ucc.nau.edu/biber/Web text types.ppt
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Summary of analysis
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