Capturing patterns of linguistic interaction in a parsed corpus A methodological case study Sean Wallis Survey of English Usage University College London

Capturing linguistic interaction... Parsed corpus linguistics Intra-structural priming Experiments –Attributive AJPs before a noun –Embedded postmodifying clauses –Sequential postmodifying clauses –Speech vs. writing Conclusions The handout explains the analytical method in more detail (so read it later!)

Parsed corpus linguistics An example tree from ICE-GB (spoken) S1A-006 #23

Parsed corpus linguistics Three kinds of evidence may be obtained from a parsed corpus  Frequency evidence of a particular known rule, structure or linguistic event  Coverage evidence of new rules, etc.  Interaction evidence of the relationship between rules, structures and events This evidence is necessarily framed within a particular grammatical scheme –How might we evaluate this grammar?

Intra-structural priming Priming effects within a structure –Study repeating an additive step in structures Consider –a phrase or clause that may (in principle) be extended ad infinitum e.g. an NP with a noun head N

Intra-structural priming Priming effects within a structure –Study repeating an additive step in structures Consider –a phrase or clause that may (in principle) be extended ad infinitum e.g. an NP with a noun head –a single additive step applied to this structure e.g. add an attributive AJP before the head N AJP

Intra-structural priming Priming effects within a structure –Study repeating an additive step in structures Consider –a phrase or clause that may (in principle) be extended ad infinitum e.g. an NP with a noun head –a single additive step applied to this structure e.g. add an attributive AJP before the head –Q. What is the effect of repeatedly applying this operation to the structure? ship N N AJP

Intra-structural priming Priming effects within a structure –Study repeating an additive step in structures Consider –a phrase or clause that may (in principle) be extended ad infinitum e.g. an NP with a noun head –a single additive step applied to this structure e.g. add an attributive AJP before the head –Q. What is the effect of repeatedly applying this operation to the structure? ship NAJP tall N AJP

Intra-structural priming Priming effects within a structure –Study repeating an additive step in structures Consider –a phrase or clause that may (in principle) be extended ad infinitum e.g. an NP with a noun head –a single additive step applied to this structure e.g. add an attributive AJP before the head –Q. What is the effect of repeatedly applying this operation to the structure? ship NAJP very greentall AJP N

Intra-structural priming Priming effects within a structure –Study repeating an additive step in structures Consider –a phrase or clause that may (in principle) be extended ad infinitum e.g. an NP with a noun head –a single additive step applied to this structure e.g. add an attributive AJP before the head –Q. What is the effect of repeatedly applying this operation to the structure? ship NAJP very greentall AJP N old

Experiment 1: analysis of results Sequential probability analysis –calculate probability of adding each AJP –error bars: Wilson intervals –probability falls second < first third < second –decisions interact –Every AJP added makes it harder to add another probability

Experiment 1: explanations? Feedback loop: for each successive AJP, it is more difficult to add a further AJP  logical-semantic constraints tend to say the tall green ship do not tend to say tall short ship or green tall ship  communicative economy once speaker said tall green ship, tends to only say ship  memory/processing constraints unlikely: this is a small structure, as are AJPs

Experiment 1: speech vs. writing Spoken vs. written subcorpora –Same overall pattern –Spoken data tends to have fewer attributive AJPs Support for communicative economy or memory/processing hypotheses? –Significance tests Paired 2x1 Wilson tests (Wallis 2011) first and second observed spoken probabilities are significantly smaller than written probability written spoken

Experiment 2: preverbal AVPs Consider adverb phrases before a verb –Results very different Probability does not fall significantly between first and second AVP Probability does fall between third and second AVP –Possible constraints (weak) communicative (weak) semantic –Further investigation needed probability

Experiment 3: postmodifying clauses Another way to specify nouns in English –add clause after noun to explicate it the ship [that was in the port] the ship [called Ariadne] –may be embedded the ship [that was in the port [we visited last week]] –or successively postmodified the ship [called Ariadne][that was in the port]

Experiment 3: (i) embedding Probability of adding a further embedded postmodifying clause falls with size –All data second < first third < first –Spoken second < first –Written third < second Compare with effect of sequential postmodification of same head

Experiment 3: (ii) sequential Probability of sequential postmodifying falls - and - for spoken data, falls, then rises –All data second < first –Spoken third > second

Experiment 3: (ii) sequential Probability of sequential postmodifying falls - and - for spoken data, falls, then rises –All data second < first –Spoken third > second –Option: count conjoins separately or treat as single item Either way, results show similar pattern –Negative feedback: the ‘in for a penny’ effect

Experiment 3: (iii) embed vs. seq Embedded vs. sequential postmodification embedding > sequence (second level) –It is slightly easier to modify the latest head than a more remote one: semantic constraints? backtracking cost? –Third level embedding < sequence (if counting conjoins) long sequences seem to be easier to construct than comparable layers of embedding

Conclusions A method for evaluating interactions along grammatical axes –General purpose, robust, structural –More abstract than ‘linguistic choice’ experiments –Depends on a concept of grammatical distance along an axis, based on the chosen grammar Method has philosophical implications –Grammar viewed as outcome of linguistic choices –Linguistics as an evaluable observational science Signature (trace) of language production decisions –A unification of theoretical and corpus linguistics?

Potential applications Corpus linguistics –Optimising existing grammatical framework e.g. coordination, compound nouns –Comparing genres/languages/periods Theoretical linguistics –Comparing different grammars, same language Psycholinguistics –Search for evidence of language production constraints in spontaneous speech corpora speech and language therapy language acquisition and development

References Nelson, G., Wallis, S. & Aarts, B. (2002) Exploring natural language. Benjamins. Pickering, M. & Ferreira, V. (2008) Structural priming. Psychological Bulletin 134, 427–459. Wallis, S.A. (2011) Comparing χ² tests for separability. Survey of English Usage. For explanation of the analysis method see the handout! For more detail and a draft of the full paper see