The Psycholinguistics of Ellipsis Colin Phillips & Dan Parker

1. The Psycholinguistics of EllipsisColin Phillips & Dan Parker Department of LinguisticsNeuroscience & Cognitive Science ProgramUniversity of Maryland languagescience.umd.edu

2. Overview • Grammatical alternatives • Experimental investigations of ellipsis: 3 leading themes • Spoiler: these themes don’t resolve today’s debate • Theme #1: mismatching antecedents • Interlude: theories and experiments on wh-movement and anaphora • Theme #2: accessing information about antecedents • Theme #3: does size matter (or distance)? Slides available at http://www.ling.umd.edu/colin, under downloadable papers

3. Alternatives A. Nature of antecedent semantic/ discourse syntactic (roughly) B. Content of ellipsis site Dalrymple et al. 1991 Hardt 1993, etc. Many! detailed structure pointer/ anaphor C. Derivational status of structure at ellipsis site Sag 1976, Williams 1977, Fiengo & May 1994, etc. only pre spell-out throughout only post spell-out Baltin Li Merchant

4. Experiments on Ellipsis: Three Themes • Mismatching antecedentsWhat to make of mismatches between antecedent and ellipsis sitee.g., Seeing the comet was nearly impossible, but John did __. • Accessing information about antecedents • Does size (or distance) matter?

5. Alternatives A. Nature of antecedent Consistent judgments/RTs Interesting stories Early days in testing what’s inside/outside grammar semantic/ discourse syntactic (roughly) B. Content of ellipsis site Dalrymple et al. 1991 Hardt 1993, etc. detailed structure Mismatch Studies Mostly acceptability ratings Exploring grammatical status of mismatches e.g., Arregui, Clifton, Frazier, & Moulton, 2006; Kim, Kobele, Runner, & Hale, 2010 pointer/ anaphor C. Derivational status of structure at ellipsis site only pre spell-out throughout only post spell-out Baltin Li Merchant

6. Experiments on Ellipsis: Three Themes • Mismatching antecedentsWhat to make of mismatches between antecedent and ellipsis sitee.g., Seeing the comet was nearly impossible, but John did __. • Accessing information about antecedentsDoes processing of the ellipsis site involve accessing words from the antecedent (semantics or phonology)? Are binding relations between elided and non-elided material rapidly computed? • Does size (or distance) matter?

7. Alternatives A. Nature of antecedent Various interesting effects Shows rapid access toantecedent … but does thisshow what’s in ellipsis site? semantic/ discourse syntactic (roughly) B. Content of ellipsis site Dalrymple et al. 1991 Hardt 1993, etc. detailed structure Accessing Antec. Features Cross-modal lexical decision Visual world eye-tracking Self-paced reading, etc. e.g., Shapiro & Hestvik 1995; Snider & Runner 2010; Yoshida, Dickey, & Sturt, 2011; Kaan, Wijnen, & Swaab, 2004 pointer/ anaphor C. Derivational status of structure at ellipsis site only pre spell-out throughout only post spell-out Baltin Li Merchant

8. Experiments on Ellipsis: Three Themes • Mismatching antecedentsWhat to make of mismatches between antecedent and ellipsis sitee.g., Seeing the comet was nearly impossible, but John did __. • Accessing information about antecedentsDoes processing of the ellipsis site involve accessing words from the antecedent (semantics or phonology)? Are binding relations between elided and non-elided material rapidly computed? • Does size (or distance) matter?Does resolution of ellipsis become slower/harder for larger/distant antecedents?

9. Alternatives A. Nature of antecedent A number of studies, andemerging consensus that size does not matter (different morals drawn) … but are thefinings conclusive? semantic/ discourse syntactic (roughly) B. Content of ellipsis site Dalrymple et al. 1991 Hardt 1993, etc. detailed structure Size/Distance Studies “Got it” semantic judgments Self-paced reading Speed-accuracy tradeoff (SAT) e.g., Murphy 1985; Frazier & Clifton 2001; Martin & McElree 2008 pointer/ anaphor C. Derivational status of structure at ellipsis site only pre spell-out throughout only post spell-out Baltin Li Merchant

10. Alternatives A. Nature of antecedent semantic/ discourse syntactic (roughly) B. Content of ellipsis site Dalrymple et al. 1991 Hardt 1993, etc. detailed structure pointer/ anaphor C. Derivational status of structure at ellipsis site only pre spell-out throughout only post spell-out Baltin Li Merchant

11. They agree: detailed structural representation in ellipsis site They disagree: derivational “timing” They don’t tell us: how their derivations relate to real-time mechanisms So we’ll make something up for them … A. Very little relation (cf. Townsend & Bever, 2001)  no predictions B. Real-time mechanism incrementally builds a representation that includes sound (PF), meaning (LF), plus mediating structure  identical predictions Any evidence of building structure at ellipsis site fits all 3 proposals C. Derivational status of structure at ellipsis site Moral For psycholinguists to help with your grammatical disputes, it helps to come clean about your mentalistic commitments (for menu of options, cf. Phillips & Lewis 2010) only pre spell-out throughout only post spell-out Baltin Li Merchant

12. Theme #1: Mismatches “This information could have been released by Gorbachev, but he chose not to ___.” release this information attributed to Daniel Schorr, NPR cited in Hardt 1993

13. Theme #1: Mismatches • ‘Acceptability cline’ across various forms of antecedent-ellipsis mismatches (Arregui, Clifton, Frazier, & Moulton 2006; Kim, Kobele, Runner, & Hale 2010) • Various judgment studies fine-tune generalizationsAppeal to parser properties to account for mismatches • Active-Passive > Passive-Activea. The advisor praised the student, and the old school-master was.b. The student was praised by the old school-master, and the advisor did too.Verbal Gerunds > Nominal Gerundsa. Singing the arias tomorrow night will be difficult, but Maria will.b. Tomorrow night’s singing of the arias will be difficult, but Maria will.Category N-VP > Adj-VPa. The criticism of Roy was harsh, but Kate didn’t.b. The report was critical of Roy, but Kate didn’t.

14. Theme #1: Mismatches Arregui, Clifton, Frazier, & Moulton 2006 • VPE requires syntactic identity… standard notion • VPE mismatches are ungrammatical • Partial acceptability reflects repair • VP-repair (‘recycling’) • Transform mismatching antecedent • Rules guide repair process • Cline reflects amount of repair work Kim, Kobele, Runner, & Hale 2010 • VPE requires syntactic identity… in a novel gram. analysis • VPE mismatches are grammatical • Partial acceptability reflects search • Search heuristics • Search for matching antecedent • Constraints guide search for matching antecedent • Cline reflects amount of search work

15. Interlude Experimental findings in other theoretically contentious domains

16. Competing accounts of ellipsis Null structure at foot of dep.All of today’s speakers He ate something but I don’t know what he ate __. He ate something but I don’t know what. No/minimal null structureAnaphor/‘pointer’ account

17. Competing accounts of wh-dependencies Null structure at foot of dep.Transformational Grammar(--> Projection Principle) What do Englishmen cook gap/trace/copy Direct AssociationHPSG/GPSGCategorial GrammarDependency Grammaretc. What do Englishmen cook

18. Competing accounts of anaphora Pronominalization(Postal)Movement theory of control/reflexives (Hornstein et al.) John thinks that Mary hates him John. Standard viewAnaphor points to content elsewhere in syntax/discourse John thinks that Mary hates him.

19. Experiments as Theory Arbitrators Many of the themes raised in experiments on ellipsis have been investigated in experiments on wh-dependencies and anaphora. Wh-dependencies: much discussion of whether expt. findings are decisive regarding gaps/traces vs. direct association. Conclusion: the timing evidence probably isn’t decisive (yet). Gibson & Hickok 1993; Phillips & Wagers 2007; Kempen, LSA 2011 So it’s interesting to see parallel arguments being presented as theoretically decisive in the case of ellipsis. Anaphora: nobody thinks they’re testing pronominalization etc.

20. Cross-modal Priming Semantic Associate Priming Swinney, Ford, Frauenfelder, & Bresnan 1988; Nicol & Swinney 1989; McKoon, Ratcliff & Ward 1994; Nicol, Fodor, & Swinney 1994 Rhyme Priming Tanenhaus, Carlson, & Seidenberg 1985 The policeman saw the boy that the crowd at the party accused __ of the crime. girl group The man was surprised at which beer/winethe judges awarded the first prize to __. fear

21. Eye-fixations in visual world Q: Can you tell me… Wh: … what Emily was eating the cake with ___ ? YN: … if Emily was eating the cake with the fork? 1. eat 2. wash Fixations on picture of cake WH YN 400 ms Verb Onset Omaki, Trock, Wagers, Lidz & Phillips, 2009

22. Pronouns & Lexical Properties • In pronoun generation (production) phonological properties of the antecedent are accessed (Schmitt, Meyer, & Levelt 1999) • In pronoun comprehension, effects of lexical frequency of the antecedent (van Gompel & Majid 2004; Lago, Chow, & Phillips in prep.) • These effects show how antecedents are accessedFew would consider them as evidence for Postal-style pronominalization

23. Point of the Interlude … • In wh-dependencies and anaphora, many interesting experiments show how antecedent information is accessed, and when.This is all very useful for building an account of real-time computation. • But evidence on access to antecedent properties does not show whether there’s unpronounced structure at the foot of the dependencyFor any argument for full structure at an ellipsis site, ask this question: Would the same argument convince us of the need for (i) traces/gaps for wh-movement, or (ii) a transformational analysis of anaphora?

24. Theme #2 Accessing Antecedents

25. Accessing Words in Antecedent Cross-modal lexical decision shows semantic priming of noun inside antecedent (Shapiro, Hestvik, Lesan, & Garcia, 2003) The old professor [VP loved the ocean], and the teenager […] did __ too …  Syntactically-defined antecedent accessed at ellipsis site. PACIFIC TEACHER

26. Accessing Antecedent Properties Experiment 1: semantic associates lock The security guard opened the lock, and the night manager did too. These arguments for syntactic structure in ellipsis parallel earlier findings on wh-dependencies and pronoun processing. key Experiment 2: phonological associates The customer dropped the lock, and the manager did too. log “Only if syntactic structure is present in ellipsis site should phonological information be reactivated.” lock Snider & Runner, AMLaP2010 (& Sat. 10:30am)

27. Fast Use of Syntactic Constraints • Rapid building of binding relations in sluicing (Yoshida, Dickey, & Sturt 2011)Jane’s {grandfather|grandmother} told some stories at the family reunion, but we couldn’t remember which story about himself … [sentence continues]Gender mismatch effect at reflexive when sluicing is a viable option(No corresponding effect at reflexive when pied-piped wh-PP blocks sluicing) • Rapid sensitivity to islands in sluicing vs. sprouting (Yoshida et al. 2010)Nick’s father was startled … because he smoked secretly in the garden because he smoked something in the garden… but it wasn’t clear what …Evidence of immediate sensitivity to islands for sprouting vs. sluicing • Clever contrasts – but they motivate structure at ellipsis site to the same extent that connectivity effects in wh-movement motivate traces.

28. Fast resolution of gapping • ERPs suggest rapid detection of implausibility in gapped sentences (Kaan, Wijnen, & Swaab 2004)Ron took the planks for the bookcase, and Bill __ the hammer …Ron sanded the planks for the bookcase, and Bill __ the hammer … N400 to implausible verb-noun combination “the sentence processor […] reconstructs the verb information at the earliest possible occasion” (p. 584) Any mechanism that gets the meaning can capture this.

29. Theme #3: Does size matter? • “The canonical interpretation of a literal copy mechanism is that copying more information should take more time. One could simply assert that ‘copying’ does not require time, but we suggest that in that case, the notion ‘copy’ is no longer explanatory.” (Martin & McElree 2008, p. 894) • A number of studies have tested whether size/complexity affects the time needed for ellipsis resolution.Mixed results.But most currently assume that the evidence shows no size cost. • Size effect ≠ copy mechanismNo size effect = no copy mechanismReason: merely accessing a complex antecedent could take a while

30. Yes – size matters! • Shorter antecedents yield shorter response times in an end-of-sentence “got it” task (Murphy 1985) Short Antecedent: Jimmy swept the tile floor behind the chair Long Antecedent : Jimmy swept the tile floor behind the chair free of hair and cigarettes. Ellipsis: Later, his uncle did too. • Size effect only holds for nearby antecedents. It disappears when distance between antecedent and ellipsis is increased by adding an intervening sentence.Evidence criticized by Tanenhaus & Carlson (1990) based on poss. confounds long antecedent: 244ms slower RTs

31. No – it doesn’t! • Widely cited lack of antecedent size effects in VPE (Frazier & Clifton 2000, 2001)Short Antecedent: Sarah left her boyfriend last May.Long Antecedent : Sarah got up the courage to leave her boyfriend last May.Ellipsis: Tina did too. • F&C conclude cost free copying … what Martin & McElree call non-explanatory • Although F&C’s paper reports multiple studies, this is the only specific test of the antecedent size effect.Measure: reading time to final region in self-paced reading – not best practice.Small study: half the size of a regular study ( reduced power), intermittent comprehension questions.No effect? Numerical slowdown in some comparisons (50ms), not reliable.

32. No – it doesn’t! Version 2 – Martin & McElree 2008 Speed-Accuracy Tradeoff (SAT) Memory Access

33. SAT: Possible Outcomes Asymptotic difference Reflects the strength of the representation or the likelihood of completing a parse/process. Rate/intercept difference Reflects the speed of processing: how quickly information accumulates continuously, or the differences in an underlying discrete finishing time distribution.

34. VP-complexity manipulation (Expt 3) The history professor understood Roman mythology …The history professor understood Rome’s swift and brutal destruction of Carthage …… but the principal was displeased to learn that the overworked students […] did not.… but the principal was displeased to learn that the overly worn books […] did not no effect of complexityon dynamics or asymptote Antecedent distance effect (Expt 1) distance affects asymptote,but not dynamics Martin & McElree 2008

35. VP-complexity manipulation (Expt 3) The history professor understood Roman mythology …The history professor understood Rome’s swift and brutal destruction of Carthage …… but the principal was displeased to learn that the overworked students […] did not.… but the principal was displeased to learn that the overly worn books […] did not no effect of complexityon dynamics or asymptote But … The time course profile measures the sensicality judgment task. Task requires only matching of subject with antecedent verb. Added complexity isn’t relevant. Needed: a version of this study where entire VP is task relevant. Martin & McElree 2008

36. Cautionary Note from Wh-studies • Larger antecedents sometimes correspond to shorter reading times at foot of wh-dependency (Hofmeister 2007)What did the reporter that Scooter avoided discuss …Which poll did the reporter that Scooter avoided discuss …Which political poll did the reporter that Scooter avoided discuss …It was a communist who the members of the club banned …It was an alleged communist who the members of the club banned …It was an alleged Venezuelan communist who the members of the club banned … • Hofmeister attributes effects to elaborationor depth of encoding in memory.Moral: bigger antecedents aren’t all harder

37. Conclusions A. Nature of antecedent Psycholinguists are helping with the overgenerationproblem that syntactic theories of ellipsis face. Many interesting findings about rapid access to information in ellipsis resolution.But this is different than showing structure in the ellipsis site. No experiments yet resolve the differences between today’s speakers.A linking hypothesis from syntactic derivations to real-time computations would be a good start. semantic/ discourse syntactic (roughly) B. Content of ellipsis site Dalrymple et al. 1991 Hardt 1993, etc. detailed structure pointer/ anaphor C. Derivational status of structure at ellipsis site only pre spell-out throughout only post spell-out Baltin Li Merchant

38. Thanks to … • NSF DGE-0801465 IGERT training program in language scienceNSF BCS-0948554, Structure Generation in Language Comprehension • Masaya Yoshida, Matt Wagers, RoumiPancheva for filling many holes in our knowledge

39. Annotated Bibliography of Experimental Studies on Ellipsis

40. Bibliography - Ellipsis Arregui, A., Clifton Jr., C. L. Frazier & K. Moulton. (2006). Processing elided VPs with flawed antecedents. Journal of Memory & Language 55:232–246. [Uses acceptability and self-paced reading studies to measure mismatch effects. Argues for a repair strategy to create an appropriate antecedent in cases of syntactic mismatch] Frazier, L. & Clifton Jr., C. (1998). Comprehension of sluiced sentences. Language andCognitive Processes 13: 499-520. [Investigates a variety of factors that affect the processing of sluiced sentences (e.g. focus, overt/covert antecedents) using self-paced reading and eye-tracking measures.] Frazier, L., & Clifton Jr., C. (2001). Parsing coordinates and ellipsis: Copy alpha. Syntax: 4(1), 1–22. [Reports a self-paced reading study to measure antecedent size effects. Evidence for the absence of size effects, and argues for a “Cost-free” copy mechanism. That study is reported in (somewhat) more detail in Frazier et al. 2000, J. Psycholing. Res.] Frazier, L. & Clifton Jr., C. (2005). The syntax-discourse divide: Processing ellipsis. Syntax: 8(1), 121–174. [Acceptability and self-paced reading studies testing for structure at ellipsis site. Argues for structure at the ellipsis site. See also Frazier & Clifton (2006)]

41. Bibliography - Ellipsis Kaan, E., Wijnen, F., & Swaab, T. Y. (2004). Gapping: Electrophysiological evidence for immediate processing of “missing” verbs in sentence comprehension. Brain and Language: 89(3), 584–592.[ERP study investigating the time-course of gapping resolution. N400 effects suggest rapid integration of the elided verb at the gap site.] Gregory, H. and Lappin, S. (1997). A computational model of ellipsis resolution. In Geert-Jan Kruijff, Glyn V. Morrill, and Richard T. Oehrle, editors, Formal Grammar: proceedings of the conference. [Offers an implemented algorithm to capture syntactic reconstruction in ellipsis] Kim, C., Kobele, G., Runner, J. & Hale, J. (to appear) The Acceptability Cline in VP Ellipsis. Syntax. [Uses magnitude estimation acceptability judgments to measure syntactic mismatch effects. Outlines a computational model in which mismatching VPE effects result from violating parsing heuristics] Kim, C. & Runner, J. (in press). Discourse parallelism and VP ellipsis. UMass Occasional Papers in Linguistics: Ellipsis. [Several magnitude estimation studies investigating mismatch effects in VPE]

42. Bibliography - Ellipsis Martin, A. E., & McElree, B. (2008). A content-addressable pointer mechanism underlies comprehension of verb-phrase ellipsis. Journal of Memory and Language: 58, 879–906. [Several speed-accuracy tradeoff experiments investigating the mechanisms of antecedent access and retrieval. Argues for a pointer mechanism] Martin, A. E., & McElree, B. (2009). Memory operations that support language comprehension: Evidence from verb-phrase ellipsis. Journal of Experimental Psychology: Learning Memory & Cognition: 35, 1231-1239.[Speed-accuracy tradeoff experiment investigating the mechanisms of retrieval. Measures the effects of proactive and retroactive interference using ellipsis constructions] Murphy, G. (1985). Processes of understanding anaphora. Journal of Memory and Language: 24:290–303. [Uses a “Got It” test of comprehension to measure size and distance effects. Shows that size matters for nearby antecedents, but not distant antecedents] Poirier, J., Wolfinger, K., Spellman, L. & Shapiro, L. (2010). The Real-Time Processing of Sluiced Sentences. Journal of Psycholinguistic Research. 39:411–427. [Cross-modal lexical decision study investigating antecedent access in sluicing. Shows that the antecedent object NP is accessed, but not the subject NP]

43. Bibliography - Ellipsis Shapiro, L. P., Hestvik, A., Lesan, L., & Garcia, A. R. (2003). Charting the time-course of VP-ellipsis sentence comprehension: Evidence for an initial and independent structural analysis. Journal of Memory and Language: 49(1), 1–19. [Cross-modal lexical decision study investigating antecedent access in VPE. Shows that the syntactic VP antecedent is accessed, and argues for syntactic reconstruction in ellipsis. See also Shapiro & Hestvik (1995)] Snider, N. & Runner, J. (2010). "Structural Parallelism Aids Ellipsis and Anaphor Resolution: Evidence from Eye Movements to Semantic and Phonological Neighbors," 16th Annual Conference on Architectures and Mechanisms for Language Processing, York, UK. [Slides retrieved from Snider’s home page. Examines antecedent retrieval using visual world eye-tracking. Argues that semantic and phonological neighbors are activated as a consequence of antecedent retrieval in VPE. Argues for structure at ellipsis site]

44. Bibliography - Ellipsis Streb, J., E. Hennighausen. and Rosler, F. (2004). Different anaphoric expressions are investigated by event-related brain potentials, Journal of Psycholinguistic Research: 33(3), 175-201.[ERP study investigating distance effects. Shows that comprehension times increase with distance to the antecedent. Also, a LAN-like effect suggests that ellipsis is resolved during syntactic parsing steps] Tanenhaus, M. K., & Carlson, G. N. (1990). Comprehension of deep and surface verb phrase anaphors. Language and Cognitive Processes, 5(4), 257–280. [Uses sensicality judgments to investigate the role of syntactic parallelism in the comprehension of deep and surface anaphors. Surface anaphors make sense more often in syntactically parallel contexts than in non-parallel contexts. Parallelism does not affect judgments of deep anaphors]

45. Bibliography - Ellipsis Masaya Yoshida, Michael Walsh Dickey & Patrick Sturt, (to appear, 2010). Predictive Processing of Syntactic Structure: Sluicing and Ellipsis in Real-Time Sentence Processing. Language and Cognitive Processes. [Uses self-paced reading measures to investigate the prediction of syntactic structure in potentially sluiced constructions. Argues that parser chooses sluicing over other possible structures when possible. Argues for syntactic structure at the ellipsis site] Masaya Yoshida, Jiyeon Lee, Isaac Rottman and Michael Dickey. (to appear). Islands under the predicted structure. InJ. Sprouse & N. Hornstein (eds.), edited volume on syntax and psycholinguistics of islands. [Self-paced reading study investigating the processing of potential sluicing/sprouting structures.Argues that the parser posits the structure of ellipsis when an embedded wh-phrase is processed, based on presence/absence of a reading time cost associated with sprouting.]

46. Other works cited Dalrymple, M., Stuart, M., Shieber, S. & Pereira, F. (1991). Ellipsis and higher-order unification. Linguistics and Philosophy: 14: 399–452. Gibson, E. & Hickok, G. (1993). Sentence processing with empty categories. Language and Cognitive Processes: 8(2): 147-161. Kempen, G. (2011): Nontransformational reinterpretation of the purported psycholinguistic evidence for grammatical movement operations and movement traces. Presentation at the 85th Annual Meeting of the Linguistic Society of America. Jan 6-9. Pittsburgh, PA. Hardt, D. (1993). Verb Phrase ellipsis: Form, meaning, and processing. Ph.D. Dissertation, University of Pennsylvania. Hofmeister, P. (2007). Representational Complexity and Memory Retrieval in Language Comprehension. Ph.D. Dissertation, Stanford University. Lago, S., Chow, W. Y., & Phillips, C. (in prep.). Word frequency affects pronouns and antecedents identically: Distributional evidence. U of Maryland. McKoon, G., Ratcliff, R., & Ward, G. (1994). Testing theories of language processing: An empirical investigation of the on-line lexical decision task. Journal of Experimental Psychology: Learning, Memory, and Cognition: 20(5): 1219-1228. Nicol, J. & Swinney, D.A. (1989). The role of structure in coreference assignment during sentence comprehension.  Journal of Psycholinguistic Research, Special Issue: Sentence Processing:18: 5-19. Nicol, J., Fodor, J.D., & Swinney, D. (1994). Using Cross-Modal lexical decision tasks to investigate sentence processing. Journal of Experimental Psychology: Learninq, Memory, and Cognition: 20(5): 1229-1238.

47. Other works cited Omaki, A., Trock, A., Wagers, M., Lidz, J., Phillips, C. (2009). Active gap search in the visual world with lexical competitors. CUNY Sentence Processing Conference, 22, Davis, CA. Phillips, C., & Wagers, M. (2007). Relating Structure and Time in Linguistics and Psycholinguistics. In G. Gaskell, ed. Oxford Handbook of Psycholinguistics. Oxford University Press. Phillips, C. & Lewis, S. (2010). Derivational Order in Syntax: Evidence and Architectural Consequences. In C. Chesi, ed. Directions in Derivations. Elsevier. Schmitt, B. Meyer, A., & Levelt, W.J.M., (1999). Lexical access in the production of pronouns. Cognition:69: 313-335. Swinney, D., Ford, M., Frauenfelder, U., & Bresnah, J. (1988). On the temporal course of gap-filling and antecedent assignment during sentence comprehension. In B. Grosz, R. Kaplan. M. Macken. & 1. Sag, eds. Language structure and processing. Stanford, CA: CSLI. Tanenhaus, M.K., Carlson, G. & Seidenberg, M.S. (1985). Do listeners compute linguistic representations? In D. Dowty, L. Kartunnen & A. Zwicky, eds., Natural Language Parsing: Psychological, Computational, and Theoretical Perspectives. Cambridge University Press. Townsend, D. J., and Bever, T. G. (2001). Sentence Comprehension: The Integration of Habits and Rules. MIT Press. Van Gompel, R.P.G., & Majid, A. (2004). Antecedent frequency effects during the processing of pronouns. Cognition: 90: 255-264.