Publications

Abstract

This paper deals with the dramatic environmental, social and cultural changes on the Trobriand Islands which I experienced during 16 long- and short-term fieldtrips from 1982 to 2012. I first report on the climate change I experienced there over the years and provide a survey about the demographic changes on the Trobriand Islands – highlighting the situation in Tauwema, my village of residence on Kaile’una Island. Finally I report on the social and cultural impact these dramatic changes have for the Trobriand Islanders and their culture.

Abstract

1. Introduction 2. A generative grammar as an algorithm 3. The semantic component 4. Bibliography 1. Introduction Throughout the 20th century up to the present day grammar and semantics have been uneasy bedfellows. A look at the historical background will make it clear how this curious situation came about. 20th-century linguistics has been characterized by an almost exclusive concern with the structure of words, word groups and sentences. This concern was reinforced, especially on the American side of the Atlantic, by the sudden rise and subsequent dominance of behaviorism during the 1920s. It started in psychology but quickly permeated all the human sciences, including linguistics, until the early 1960s, when it collapsed as suddenly as it had arisen.

Abstract

Presupposition is a semantic device built into natural language to make sentences fit for use in certain contexts but not in others. A sentence carrying a presupposition thus evokes a context in which that presupposition is fulfilled. The study of presupposition was triggered by the behavior of natural language negation, which tends to preserve presuppositions either as invited inferences or as entailments. As the role of discourse became more apparent in semantics, presupposition began to be seen increasingly as a discourse-semantic phenomenon with consequences for the logic of language.

Abstract

The property of presuppositions to be sometimes preserved through embeddings, albeit often in a weakened form, is called projection. The projection problem consists in formulating the conditions under which the presuppositions of an embedded clause (a) are kept as presuppositions of the superordinate structure, or (b) remain as an invited inference that can be overruled by context, or (c) are canceled. Over the past 25 years it has been recognized that the projection problem is to be solved in the context of a wider theory of presupposition and discourse incrementation.

Abstract

Logic was discovered by Aristotle when he saw that the semantic behavior of the negation word not is different in sentences with a definite and in those with a quantified subject term. Until the early 20th century, logic remained firmly language-based, but for the past century it has been mainly a tool in the hands of mathematicians, which has meant an alienation from linguistic reality. With the help of new techniques, it is now possible to revert to the logic of language, which is seen as based on a semantic analysis of the logical words (constants) involved. This new perspective, combined with much improved insights into the semantically defined discourse dependency of natural language sentences, leads to a novel and more functionally oriented approach to logic and to a reappraisal of traditional predicate calculus, whose main fault, undue existential import, evaporates when discourse dependency, in particular the presuppositional aspect, is brought into play. Traditional predicate calculus is seen to have a much greater logical power and a much greater functionality than modern predicate calculus. There is also full isomorphism, neglected in modern logic, between traditional predicate calculus and propositional calculus, which raises the question of any possible deeper causes.

Abstract

Virtual objects are objects thought up by a thinking individual. Although 20th-century philosophy has tried to ban them from ontology, they make it impossible to account for the truth of sentences such as Apollo was worshipped in the island of Delos, in which a property is assigned to the nonexisting, virtual entity Apollo. Such facts are the reason why virtual objects are slowly being recognized again.

Abstract

Some predicates are ‘factive’ in that they induce the presupposition that what is said in their subordinate that clause is true.

Abstract

The term ‘donkey sentences’ derives from the medieval philosopher Walter Burleigh, whose example sentences contain mention of donkeys. The modern philosopher Peter Geach rediscovered Burleigh's sentences and the associated problem. The problem is that natural language anaphoric pronouns are sometimes used in a way that cannot be accounted for in terms of modern predicate calculus. The solution lies in establishing a separate category of anaphoric pronouns that refer via the intermediary of a contextually given antecedent, possibly an existentially quantified expression.

Abstract

A discourse domain D is a form of middle-term memory for the storage of the information embodied in the discourse at hand. The information carried by a new utterance u is added to D (u is incremented to D). The processes involved and the specific structure of D are a matter of ongoing research.

Abstract

Discourse semantics (DSx) is based on the fact that the interpretation of uttered sentences is dependent on and co-determined by the information stored in a specialized middle-term cognitive memory called discourse domain (D). DSx studies the structure and dynamics of Ds and the conditions to be fulfilled by D for proper interpretation. It does so in the light of the truth-conditional criteria for semantics, with an emphasis on intensionality phenomena. It requires the assumption of virtual entities and virtual facts. Any model-theoretic interpretation holds between discourse structures and pre-established verification domains.

Abstract

This article places the debate between Chomskyan autonomous syntax and Generative Semantics in the context of the first beginnings of syntactic theory set out in Perì suntáxeõs ('On syntax') by Apollonius Dyscolus (second century CE). It shows that, theoretically speaking, the Apollonian concept of syntax implied an algorithmically organized system of composition rules with lexico-semantic, not a sound-based, input, unlike Apollonius's strictly sound-based postulated rule systems for the composition of phonemes into syllables and of syllables into words. This meaning-based notion of syntax persisted essentially unchanged (though refined by Sanctius during the sixteenth century) until the 1930s, when structuralism began to take the notion of algorithmically organized rule systems for the generation of sentences seriously. This meant a break with the Apollonian meaning-based approach to syntax. The Generative Semantics movement, which arose during the 1960s but was nipped in the bud, implied a return to the tradition, though with much improved formal underpinnings.

Abstract

Aristotle's importance in the professional study of language consists first of all in the fact that he demythologized language and made it an object of rational investigation. In the context of his theory of truth as correspondence, he also provided the first semantic analysis of propositions in that he distinguished two main constituents, the predicate, which expresses a property, and the remainder of the proposition, referring to a substance to which the property is assigned. That assignment is either true or false. Later, the ‘remainder’ was called subject term, and the Aristotelian predicate was identified with the verb in the sentence. The Aristotelian predicate, however, is more like what is now called the ‘comment,’ whereas his remainder corresponds to the topic. Aristotle, furthermore, defined nouns and verbs as word classes. In addition, he introduced the term ‘case’ for paradigmatic morphological variation.

Abstract

There is a growing awareness among theoretical linguists and philosophers of language that the linguistic definition of lexical meanings, which must be learned when one learns a language, underdetermines not only full utterance interpretation but also sentence meaning. The missing information must be provided by cognition – that is, either general encyclopedic or specific situational knowledge. This fact crucially shows the basic insufficiency of current standard model-theoretic semantics as a paradigm for the analysis and description of linguistic meaning.

Abstract

The lexical conditions, also known as satisfaction conditions, of a predicate P are the conditions that must be satisfied by the term referents of P for P applied to these term referents to yield a true sentence. In view of presupposition theory it makes sense to distinguish two categories of lexical conditions, the preconditions that must be satisfied for the sentence to be usable in any given discourse, and the update conditions which must be satisfied for the sentence to yield truth.

Abstract

The widely prevailing view that standard bivalent logic is the only possible sound logical system, imposed by metaphysical necessity, has been shattered by the development of multivalent logics during the 20th century. It is now clear that standard bivalent logic is merely the minimal representative of a wide variety of viable logics with any number of truth values. These viable logics can be subdivided into families. In this article, the Kleene family and the PPCn family are subjected to special examination, as they appear to be most relevant for the study of the logical properties of human language.

Abstract

The Data Category Registry is one of the ISO initiatives towards the establishment of standards for Language Resource management, creation and coding. Successful application of the DCR depends on the availability of tools that can interact with it. This paper describes the first steps that have been taken to provide users of the multimedia annotation tool ELAN, with the means to create references from tiers and annotations to data categories defined in the ISO Data Category Registry. It first gives a brief description of the capabilities of ELAN and the structure of the documents it creates. After a concise overview of the goals and current state of the ISO DCR infrastructure, a description is given of how the preliminary connectivity with the DCR is implemented in ELAN

Abstract

Turn-taking in conversation is a cognitively demanding process that proceeds rapidly due to interlocutors utilizing a range of cues
to aid prediction. In the present study we set out to test recent claims that content question words (also called wh-words) sound similar within languages as an adaptation to help listeners predict
that a question is about to be asked. We test whether upcoming questions can be predicted based on the first phoneme of a turn and the prior context. We analyze the Switchboard corpus of English
by means of a decision tree to test whether /w/ and /h/ are good statistical cues of upcoming questions in conversation. Based on the results, we perform a controlled experiment to test whether
people really use these cues to recognize questions. In both studies
we show that both the initial phoneme and the sequential context help predict questions. This contributes converging evidence that elements of languages adapt to pragmatic pressures applied during
conversation.

Abstract

Incremental sentence generation imposes special constraints on the representation of the grammar and the design of the formulator (the module which is responsible for constructing the syntactic and morphological structure). In the model of natural speech production presented here, a formalism called Segment Grammar is used for the representation of linguistic knowledge. We give a definition of this formalism and present a formulator design which relies on it. Next, we present an object- oriented implementation of Segment Grammar. Finally, we compare Segment Grammar with other formalisms.

Abstract

One of the defining features of the Southern Vanuatu language family is the echo-subject (ES) marker (Lynch 2001: 177-178). Canonically, an ES marker indicates that the subject of the clause is coreferential with the subject of the preceding clause. This paper begins with a survey of the various ES systems found in Southern Vanuatu. Two prominent differences amongst the ES systems are: a) the level of obligatoriness of the ES marker; and b) the level of grammatical integration between an ES clauses and the preceding clause. The variation found amongst the ES systems reveals a clear path of grammaticalisation from the VP coordinator *ma in Proto–Southern Vanuatu to the various types of ES marker in contemporary Southern Vanuatu languages

Abstract

One of the most pressing issues in dis-
continuous constituency transition-based
parsing is that the relevant information for
parsing decisions could be located in any
part of the stack or the buffer. In this pa-
per, we propose a solution to this prob-
lem by replacing the structured percep-
tron model with a recursive neural model
that computes a global representation of
the configuration, therefore allowing even
the most remote parts of the configura-
tion to influence the parsing decisions. We
also provide a detailed analysis of how
this representation should be built out of
sub-representations of its core elements
(words, trees and stack). Additionally, we
investigate how different types of swap or-
acles influence the results. Our model is
the first neural discontinuous constituency
parser, and it outperforms all the previ-
ously published models on three out of
four datasets while on the fourth it obtains
second place by a tiny difference.

Abstract

A common Dutch writing error is to confuse a word ending in -d with a neighbor word ending in -dt. In this paper we describe the development of a machine-learning-based disambiguator that can determine which word ending is appropriate, on the basis of its local context. We develop alternative disambiguators, varying between a single monolithic classifier and having multiple confusable experts disambiguate between confusable pairs. Disambiguation accuracy of the best developed disambiguators exceeds 99%; when we apply these disambiguators to an external test set of collected errors, our detection strategy correctly identifies up to 79% of the errors.

Abstract

The current study examines, for the first time, the viewpoint preferences of signing children in expressing spatial relations that require imposing a viewpoint (left-right, front-behind). We elicited spatial descriptions from deaf children (4–9 years of age) acquiring Turkish Sign Language (TİD) natively from their deaf parents and from adult native signers of TİD. Adults produced these spatial descriptions from their own viewpoint and from that of their addressee depending on whether the objects were located on the lateral or the sagittal axis. TİD-acquiring children, on the other hand, described all spatial configurations from their own viewpoint. Differences were also found between children and adults in the type of linguistic devices and how they are used to express such spatial relations.

Abstract

Motivated form-meaning mappings are pervasive in sign languages, and iconicity has recently been shown to facilitate sign learning from early on. This study investigated the role of iconicity for language acquisition in Turkish Sign Language (TID). Participants were 43 signing children (aged 10 to 45 months) of deaf parents. Sign production ability was recorded using the adapted version of MacArthur Bates Communicative Developmental Inventory (CDI) consisting of 500 items for TID. Iconicity and familiarity ratings for a subset of 104 signs were available. Our results revealed that the iconicity of a sign was positively correlated with the percentage of children producing a sign and that iconicity significantly predicted the percentage of children producing a sign, independent of familiarity or phonological complexity. Our results are consistent with previous findings on sign language acquisition and provide further support for the facilitating effect of iconic form-meaning mappings in sign learning.

Abstract

This paper describes ongoing research aiming at the description of variation in speech as represented by asynchronous articulatory features. We will first illustrate how distances in the articulatory feature space can be used for event detection along speech trajectories in this space. The temporal structure imposed by the cosine distance in articulatory feature space coincides to a large extent with the manual segmentation on phone level. The analysis also indicates that the articulatory feature representation provides better such alignments than the MFCC representation does. Secondly, we will present first results that indicate that articulatory features can be used to probe for acoustic differences in the onsets of Dutch singulars and plurals.

Abstract

This paper builds on previous work that aims at unraveling the structure of the speech signal by means of using probabilistic representations. The context of this work is a multi-pass speech recognition system in which a phone lattice is created and used as a basis for a lexical search in which symbolic mismatches are allowed at certain costs. The focus is on the optimization of the costs of phone insertions, deletions and substitutions that are used in the lexical decoding pass. Two optimization approaches are presented, one related to a multi-pass computational model for human speech recognition, the other based on a decoding in which Bayes’ risks are minimized. In the final section, the advantages of these optimization methods are discussed and compared.

Abstract

This paper investigates the processes in comprehending spoken noun-noun compounds, using data from the BALDEY database. BALDEY contains lexicality judgments and reaction times (RTs) for Dutch stimuli for which also linguistic information is included. Two different approaches are combined. The first is based on regression by Dynamic Survival Analysis, which models decisions and RTs as a consequence of the fact that a cumulative density function exceeds some threshold. The parameters of that function are estimated from the observed RT data. The second approach is based on DIANA, a process-oriented computational model of human word comprehension, which simulates the comprehension process with the acoustic stimulus as input. DIANA gives the identity and the number of the word candidates that are activated at each 10 ms time step.

Both approaches show how the processes involved in comprehending compounds change during a stimulus. Survival Analysis shows that the impact of word duration varies during the course of a stimulus. The density of word and non-word hypotheses in DIANA shows a corresponding pattern with different regimes. We show how the approaches complement each other, and discuss additional ways in which data and process models can be combined.

Abstract

The Papuan languages of the central Solomon Islands are a negatively defined areal grouping: They are those four or possibly five languages in the central Solomon Islands that do not belong to the Austronesian family. Bilua (Vella Lavella), Touo (Rendova), Lavukaleve (Russell Islands), Savosavo (Savo Island) and possibly Kazukuru (New Georgia) have been identified as non-Austronesian since the early 20th century. However, their affiliations both to each other and to other languages still remain a mystery. Heterogeneous and until recently largely undescribed, they present an interesting departure from what is known both of Austronesian languages in the region and of the Papuan languages of the mainland of New Guinea.

Abstract

About two years ago, the Max Planck Institute for Psycholinguistics in Nijmegen, The Netherlands, started an initiative to install regional language archives in various places around the world, particularly in places where a large number of endangered languages exist and are being documented. These digital archives make use of the LAT archiving framework [1] that the MPI has developed
over the past nine years. This framework consists of a number of web-based tools for depositing, organizing and utilizing linguistic resources in a digital archive. The regional archives are in principle autonomous archives, but they can decide to share metadata descriptions and language resources with the MPI archive in Nijmegen and become part of a grid of linked LAT archives. By doing so, they will also take advantage of the long-term preservation strategy of the MPI archive. This paper describes the reasoning
behind this initiative and how in practice such an archive is set up.

Abstract

Even advanced Spanish speakers of second language English tend to confuse the pronouns ‘he’ and ‘she’, often without even noticing their mistake (Lahoz, 1991). A study by AntónMéndez (2010) has indicated that a possible reason for this error is the fact that Spanish is a pro-drop language. In order to test this hypothesis, we used an extension of Dual-path (Chang, 2002), a computational cognitive model of sentence production, to simulate two models of bilingual speech production of second language English. One model had Spanish (ES) as a native language, whereas the other learned a Spanish-like language that used the pronoun at all times (non-pro-drop Spanish, NPD_ES). When tested on L2 English sentences, the bilingual pro-drop Spanish model produced significantly more gender pronoun errors, confirming that pronoun dropping could indeed be responsible for the gender confusion in natural language use as well.

Abstract

This corpus study investigates how children figure out that functional modals
like must can express various flavors of modality. We examine how modality is
expressed in speech to and by children, and find that the way speakers use
modals may obscure their polysemy. Yet, children eventually figure it out. Our
results suggest that some do before age 3. We show that while root and
epistemic flavors are not equally well-represented in the input, there are robust
correlations between flavor and aspect, which learners could exploit to discover
modal polysemy.

Abstract

This paper reports two experiments with vowels and consonants as phoneme detection targets in real words. In the first experiment, two relatively distinct vowels were compared with two confusible stop consonants. Response times to the vowels were longer than to the consonants. Response times correlated negatively with target phoneme length. In the second, two relatively distinct vowels were compared with their corresponding semivowels. This time, the vowels were detected faster than the semivowels. We conclude that response time differences between vowels and stop consonants in this task may reflect differences between phoneme categories in the variability of tokens, both in the acoustic realisation of targets and in the' representation of targets by subjects.

Abstract

The emerging area of Geographic Information Systems (GIS) has proven to add an interesting dimension to many research projects. Within the language-sites initiative we have brought together a broad range of links to digital language corpora and resources. Via Google Earth's visually appealing 3D-interface users can spin the globe, zoom into an area they are interested in and access directly the relevant language resources. This paper focuses on several ways of relating the map and the online data (lexica, annotations, multimedia recordings, etc.). Furthermore, we discuss some of the implementation choices that have been made, including future challenges. In addition, we show how scholars (both linguists and anthropologists) are using GIS tools to fulfill their specific research needs by making use of practical examples. This illustrates how both scientists and the general public can benefit from geography-based access to digital language data

Abstract

This paper gives an overview of the CLARIN project [1], which aims to create a research infrastructure that makes language resources and technology (LRT) available and readily usable to scholars of all disciplines, in particular the humanities and social sciences (HSS).

Abstract

In this paper, we will give a unified account of the cross-linguistic variation in the encoding of adjectives in predicative and attributive constructions. Languages may differ in the encoding strategy of adjectives in the predicative domain (Stassen 1997), and sometimes change this strategy in the attributive domain (Verkerk 2007). We will show that the interaction of two principles, that of faithfulness to the semantic class of a lexical root and that of faithfulness to discourse functions, can account for all attested variation in the encoding of adjectives.

Abstract

Experimental sentence comprehension studies have shown that superficially similar German clauses with verb-final word order elicit very different garden-path and ERP effects. We show that a computer implementation of the Unification Space parser (Vosse & Kempen, 2000) in the form of a localist-connectionist network can model the observed differences, at least qualitatively. The model embodies a parallel dynamic parser that, in contrast with existing models, does not distinguish between consecutive first-pass and reanalysis stages, and does not use semantic or thematic roles. It does use structural frequency data and animacy information.

Abstract

Two German eye-tracking experiments tested whether top-down expectations interact with acoustically-driven word-recognition processes. Competitor objects with two synonymous names were paired with target objects whose names shared word onsets with either the dominant or the non-dominant name of the competitor. Non-dominant names of competitor objects were either introduced before the test session or not. Eye-movements were monitored while participants heard instructions to click on target objects. Results demonstrate dominant and non-dominant competitor names were considered for recognition, regardless of top-down expectations, though dominant names were always activated more strongly.

Abstract

Recent studies using phoneme detection tasks have shown that spoken-language processing is neither facilitated nor interfered with by optional assimilation, but is inhibited by violation of obligatory assimilation. Interpretation of these results depends on an assessment of their generality, specifically, whether they also obtain when listeners are processing nonnative language. Two separate experiments are presented in which native listeners of German and native listeners of Dutch had to detect a target fricative in legal monosyllabic Dutch nonwords. All of the nonwords were correct realisations in standard Dutch. For German listeners, however, half of the nonwords contained phoneme strings which violate the German fricative assimilation rule. Whereas the Dutch listeners showed no significant effects, German listeners detected the target fricative faster when the German fricative assimilation was violated than when no violation occurred. The results might suggest that violation of assimilation rules does not have to make processing more difficult per se.

Abstract

Lexical recognition is typically slower in L2 than in L1. Part of the difficulty comes from a not precise enough processing of L2 phonemes. Consequently, L2 listeners fail to eliminate candidate words that L1 listeners can exclude from competing for recognition. For instance, the inability to distinguish /r/ from /l/ in rocket and locker makes for Japanese listeners both words possible candidates when hearing their onset (e.g., Cutler, Weber, and Otake, 2006). The L2 disadvantage can, however, be dispelled: For L2 listeners, but not L1 listeners, L2 speech from a non-native talker with the same language background is known to be as intelligible as L2 speech from a native talker (e.g., Bent and Bradlow, 2003). A reason for this may be that L2 listeners have ample experience with segmental deviations that are characteristic for their own accent. On this account, only phonemic deviations that are typical for the listeners’ own accent will cause spurious lexical activation in L2 listening (e.g., English magic pronounced as megic for Dutch listeners). In this talk, I will present evidence from cross-modal priming studies with a variety of L2 listener groups, showing how the processing of phonemic deviations is accent-specific but withstands fine phonetic differences.

Abstract

This contribution emphasizes the role of multimedia data not only for archiving languages but also for creating opportunities for innovative analyses. In the case at hand, video material was collected as part of the documentation of Akhoe Haiom, a Khoisan language spoken in northern Namibia. The multimedia documentation project brought together linguistic and anthropological work to highlight connections between specialized domains, namely kinship terminology, interrogatives and reciprocals. These connections would have gone unnoticed or undocumented in more conventional modes of language description. It is suggested that such an approach may be particularly appropriate for the documentation of endangered languages since it directs the focus of attention away from isolated traits of languages towards more complex practices of communication that are also frequently threatened with extinction.

Abstract

Utilization of computer tools in linguistic research has gained importance with the maturation of media frameworks for the handling of digital audio and video. The increased use of these tools in gesture, sign language and multimodal interaction studies has led to stronger requirements on the flexibility, the efficiency and in particular the time accuracy of annotation tools. This paper describes the efforts made to make ELAN a tool that meets these requirements, with special attention to the developments in the area of time accuracy. In subsequent sections an overview will be given of other enhancements in the latest versions of ELAN, that make it a useful tool in multimodality research.

Abstract

A number of serious reasons will convince an increasing amount of researchers to store their relevant material in centers which we will call "language resource archives". They combine the duty of taking care of long-term preservation as well as the task to give access to their material to different user groups. Access here is meant in the sense that an active interaction with the data will be made possible to support the integration of new data, new versions or commentaries of all sort. Modern Language Resource Archives will have to adhere to a number of basic principles to fulfill all requirements and they will have to be involved in federations to create joint language resource domains making it even more simple for the researchers to access the data. This paper makes an attempt to formulate the essential pillars language resource archives have to adhere to.

Abstract

Although sign language-using communities exist in all areas of the world, few sign languages have been documented in detail. Sign languages occur in a variety of sociocultural contexts, ranging from sign languages used in closed village communities to officially recognized national sign languages. They may be grouped into language families on historical grounds or may participate in various language contact situations. Systematic cross-linguistic comparison reveals both significant structural similarities and important typological differences between sign languages. Focusing on information from non-Western countries, this article provides an overview of the sign languages of the world.

Abstract

We describe ViCoS, a tool for constructing and visualising conceptual spaces in the area of language documentation. ViCoS allows users to enrich existing lexical information about the words of a language with conceptual knowledge. Their work towards language-based, informal ontology building must be supported by easy-to-use workflows and supporting software, which we will demonstrate.

Abstract

This paper discusses the construction of a cross-linguistic, bimodal corpus containing three modes of expression: expressions from two sign languages, speech and gestural expressions in two spoken languages and pantomimic expressions by users of two spoken languages who are requested to convey information without speaking. We discuss some problems and tentative solutions for the annotation of utterances expressing spatial information about referents in these three modes, suggesting a set of comparable codes for the description of both sign and gesture. Furthermore, we discuss the processing of entered annotations in ELAN, e.g. relating descriptive annotations to analytic annotations in all three modes and performing relational searches across annotations on different tiers.

Abstract

The lexicons of many sign languages hold large proportions of “frozen” forms, viz. signs that are generally considered to have been formed productively (as classifier predicates), but that have diachronically undergone processes of lexicalisation. Nederlandse Gebarentaal (Sign Language of the Netherlands; henceforth: NGT) also has many of these signs (Van der Kooij 2002, Zwitserlood 2003). In contrast to the general view on “frozen” forms, a few researchers claim that these signs may be formed according to productive sign formation rules, notably Brennan (1990) for BSL, and Meir (2001, 2002) for ISL. Following these claims, I suggest an analysis of “frozen” NGT signs as morphologically complex, using the framework of Distributed Morphology. The signs in question are derived in a similar way as classifier predicates; hence their similar form (but diverging characteristics). I will indicate how and why the structure and use of classifier predicates and “frozen” forms differ. Although my analysis focuses on NGT, it may also be applicable to other sign languages.