The term linguistic performance was used by Noam Chomsky in 1960 to describe "the actual use of language in concrete situations".[1] It is used to describe both the production, sometimes called parole, as well as the comprehension of language.[2] Performance is defined in opposition to "competence"; the latter describes the mental knowledge that a speaker or listener has of language.
Part of the motivation for the distinction between performance and competence comes from speech errors: despite having a perfect understanding of the correct forms, a speaker of a language may unintentionally produce incorrect forms. This is because performance occurs in real situations, and so is subject to many non-linguistic influences. For example, distractions or memory limitations can affect lexical retrieval (Chomsky 1965:3), and give rise to errors in both production and perception. Such non-linguistic factors are completely independent of the actual knowledge of language,[3] and establish that speakers' knowledge of language (their competence) is distinct from their actual use of language (their performance).
Competence is the collection of subconscious rules that one knows when one knows a language; performance is the system which puts these rules to use.[4] [5] This distinction is related to the broader notion of Marr's levels used in other cognitive sciences, with competence corresponding to Marr's computational level.[6]
For example, many linguistic theories, particularly in generative grammar, would propose competence-based explanations for why English speakers would judge the sentence in (1) as odd. In these explanations, the sentence would be ungrammatical because the rules of English only generate sentences where demonstratives agree with the grammatical number of their associated noun.[7]
(1) *That cats is eating the mouse.
By contrast, generative theories generally provide performance-based explanations for the oddness of center embedding sentences like one in (2). According to such explanations, the grammar of English could in principle generate such sentences, but doing so in practice is so taxing on working memory that the sentence ends up being unparsable.
(2) *The cat that the dog that the man fed chased meowed.
In general, performance-based explanations deliver a simpler theory of grammar at the cost of additional assumptions about memory and parsing. As a result, the choice between a competence-based explanation and a performance-based explanation for a given phenomenon is not always obvious and can require investigating whether the additional assumptions are supported by independent evidence.[8] For example, while many generative models of syntax explain island effects by positing constraints within the grammar, it has also been argued that some or all of these constraints are in fact the result of limitations on performance.[9] [10]
See main article: Langue and parole. Published in 1916, Ferdinand de Saussure's Course in General Linguistics describes language as "a system of signs that express ideas".[11] de Saussure describes two components of language: langue and parole. Langue consists of the structural relations that define a language, which includes grammar, syntax and phonology. Parole is the physical manifestation of signs; in particular the concrete manifestation of langue as speech or writing. While langue can be viewed strictly as a system of rules, it is not an absolute system such that parole must utterly conform to langue.[12] Drawing an analogy to chess, de Saussure compares langue to the rules of chess that define how the game should be played, and parole to the individual choices of a player given the possible moves allowed within the system of rules.
In 1986, Noam Chomsky proposed a distinction similar to the competence/performance distinction, entertaining the notion of an I-Language (internal language) which is the intrinsic linguistic knowledge within a native speaker and E-Language (external language) which is the observable linguistic output of a speaker.[13]
John A. Hawkins's Performance-Grammar Correspondence Hypothesis (PGCH) states that the syntactic structures of grammars are conventionalized based on whether and how much the structures are preferred in performance.[14] Performance preference is related to structure complexity and processing, or comprehension, efficiency. Specifically, a complex structure refers to a structure containing more linguistic elements or words at the end of the structure than at the beginning. It is this structural complexity that results in decreased processing efficiency since more structure requires additional processing. This model seeks to explain word order across languages based on avoidance of unnecessary complexity in favour of increased processing efficiency. Speakers make an automatic calculation of the Immediate Constituent(IC)-to-word order ratio and produce the structure with the highest ratio. Structures with a high IC-to-word order are structures that contain the fewest words required for the listener to parse the structure into constituents which results in more efficient processing.
In head-initial structures, which includes example SVO and VSO word order, the speaker's goal is to order the sentence constituents from least to most complex.
SVO word order can be exemplified with English; consider the example sentences in (1). In (1a) three immediate constituents (ICs) are present in the verb phrase, namely VP, PP1 and PP2, and there are four words (went, to, London, in) required to parse the VP into its constituents. Therefore, the IC-to-word ratio is 3/4=75%. In contrast, in (1b) the VP is still composed of three ICs but there are now six words that are required to determine the constituent structure of the VP (went, in, the, late, afternoon, to). Thus, the ratio for (1b) is 3/6 = 50%. Hawkins proposes that speakers prefer to produce (1a) since it has a higher IC-to-word ratio and this leads to faster and more efficient processing.
1a. John [<sub>VP</sub> '''''went''''' [<sub>PP1</sub> '''''to London'''''] PP2 in the late afternoon 1b. John [<sub>VP</sub> '''''went''''' [<sub>PP2</sub> '''''in the late afternoon''''']] PP1 to London
Hawkins supports the above analysis by providing performance data to demonstrate the preference speakers have for ordering short phrases before long phrases when producing head-initial structures. The table based on English data, below, illustrates that the short prepositional phrase (PP1) is preferentially ordered before the long PP (PP2) and that this preference increases as the size differential between the two PPs increases. For example, 60% of the sentences are ordered short (PP1) to long (PP2) when PP2 was longer than PP1 by 1 word. In contrast, 99% of the sentences are ordered short to long when PP2 is longer than PP1 by 7+ words.
English prepositional phrase orderings by relative weight
| n = 323 | PP2 > PP1 by 1 word | by 2-4 | by 5-6 | by 7+ | |
|---|---|---|---|---|---|
| [V PP1 PP2] | 60% (58) | 86% (108) | 94% (31) | 99% (68) | |
| [V PP2 PP1] | 40% (38) | 14% (17) | 6% (2) | 1% (1) |
Hawkins argues that the preference for short followed by long phrases applies to all languages that have head-initial structuring. This includes languages with VSO word order such as from Hungarian. By calculating the IC-to-word ratio for the Hungarian sentences in the same way as was done for the English sentences, 2a. emerges as having a higher ratio than 2b.
2a. VP['''Döngetik''' NP['''facipöink''' NP['''az''' utcakat] ] batter wooden shoes-1PL the streets-ACC Our wooden shoes batter the streets 2b. VP['''Döngetik''' NP['''az utcakat'''] NPfacipöink ]
The Hungarian performance data (below) show the same preference pattern as the English data. This study looked at the ordering of two successive noun phrases (NPs) and found that the shorter NP followed by the longer NP is preferred in performance, and that this preference increases as the size differential between NP1 and NP2 increases.
Hungarian noun phrase orderings by relative weight
| n = 85 | mNP2 > mNP1 by 1 word | by 2 | by 3+ | |
|---|---|---|---|---|
| [V mNP1 mNP2] | 85% (50) | 96% (27) | 100% (8) | |
| [V mNP2 mNP1] | 15% (9) | 4% (1) | 0% (0) |
Hawkins' explanation of performance and word order extends to head-final structures. For example, since Japanese is a SOV language the head (V) is at the end of the sentence. This theory predicts that speakers will prefer to order the phrases in head-final sentences from long phrases to short, as opposed to short to long as seen in head-initial languages. This reversal of ordering preference is due to the fact that in head-final sentences it is the long followed by short phrasal ordering that has the higher IC-to-word ratio.
3a. Tanaka ga vp[pp[Hanako '''kara''']np['''sono''' '''hon o'''] katta] Tanaka NOM Hanako from that book ACC bought Tanako bought that book from Hanako 3b. Tanaka ga vp[np[sono hon '''o'''] pp['''Hanako kara'''] ['''katta''']
The VP and its constituents in 4. are constructed from their heads on the right. This means that the number of words used to calculate the ratio is counted from the head of the first phrase (PP in 3a. and NP in 3b.) to the verb (as indicated in bold above). The IC-to-word ratio for the VP in 3a. is 3/5=60% while the ratio for the VP in 3b. is 3/4=75%. Therefore, 3b. should be preferred by Japanese speakers since it has a higher IC-to-word ratio which leads to faster parsing of sentences by the listener.
The performance preference for long to short phrase ordering in SVO languages is supported by performance data. The table below shows that production of long to short phrases is preferred and that this preference increases as the size of the differential between the two phrases increases. For example, ordering of the longer 2ICm (where ICm is either a direct object NP with an accusative case particle or a PP constructed from the right periphery) before the shorter 1ICm is more frequent, and the frequency increases to 91% if the 2ICm is longer than the 1ICm by 9+ words.
Japanese NPo and PPm orderings by relative weight
| n = 153 | 2ICm > 1ICm by 1-2 words | by 3-4 | by 5-8 | by 9+ | |
|---|---|---|---|---|---|
| [2ICm 1ICm V] | 66% (59) | 72% (21) | 83% (20) | 91% (10) | |
| [1ICm 2ICm V] | 34% (30) | 28% (8) | 17% (4) | 9% (1) |
Tom Wasow proposes that word order arises as a result of utterance planning benefiting the speaker.[15] He introduces the concepts of early versus late commitment, where commitment is the point in the utterance where it becomes possible to predict subsequent structure. Specifically, early commitment refers to the commitment point present earlier in the utterance and late commitment refers to the commitment point present later in the utterance. He explains that early commitment will favour the listener since early prediction of subsequent structure enables faster processing. Comparatively, late commitment will favour the speaker by postponing decision making, giving the speaker more time to plan the utterance. Wasow illustrates how utterance planning influences syntactic word order by testing early versus late commitment in heavy-NP shifted (HNPS) sentences. The idea is to examine the patterns of HNPS to determine if the performance data show sentences that are structured to favour the speaker or the listener.
The following examples illustrate what is meant by early versus late commitment and how heavy-NP shift applies to these sentences. Wasow looked at two types of verbs:
Vt (transitive verbs): require NP objects.
4a. Pat VP[brought NP[a box with a ribbon around it] PP[[to the party] ] 4b. Pat VP[brought PP[to the party] NP[[a box with a ribbon around it] ]
In 4a. no heavy-NP shift has been applied. The NP is available early but does not provide any additional information about the sentence structure – the "to" appearing late in the sentence is an example of late commitment. In contrast, in 4b., where heavy-NP shift has shifted the NP to the right, as soon as "to" is uttered the listener knows that the VP must contain the NP and a PP. In other words, when "to" is uttered it allows the listener to predict the remaining structure of the sentence early on. Thus for transitive verbs HNPS results in early commitment and favors the listener.
Vp (prepositional verbs): can take an NP object or an immediately following PP with no NP object
5a. Pat VP[wrote NP[something about Chris] PP[[on the blackboard]]. 5b. Pat VP[wrote PP[on the blackboard] NP[[something about Chris.]]
No HNPS has been applied to 5a. In 5b. the listener needs to hear the word "something" in order to know that the utterance contains a PP and an NP since the object NP is optional but "something" has been shifted to later in the sentence. Thus for prepositional verbs HNPS results in late commitment and favours the speaker.
Based on the above information Wasow predicted that if sentences are constructed from the speaker's perspective then heavy-NP shift would rarely apply to sentences containing a transitive verb but would apply frequently to sentences containing a prepositional verb. The opposite prediction was made if sentences are constructed from the listener's perspective.
| Speaker's Perspective | Listener's Perspective | ||
|---|---|---|---|
| Vt | Heavy-NP shift= rare | Heavy-NP shift= relatively common | |
| Vp | Heavy-NP shift= relatively common | Heavy-NP shift =very rare |
To test his predictions Wasow analyzed performance data (from corpora data) for the rates of occurrence of HNPS for Vt and Vp and found HNPS occurred twice as frequently in Vp than in Vt, therefore supporting the predictions made from the speaker's perspective. In contrast, he did not find evidence in support of the predictions made based on the listener's perspective. In other words, given the data above, when HNPS is applied to sentences containing a transitive verb the result favors the listener. Wasow found that HNPS applied to transitive verb sentences is rare in performance data thus supporting the speaker's perspective. Additionally, when HNPS is applied to prepositional verb structures the result favors the speaker. In his study of the performance data, Wasow found evidence of HNPS frequently applied to prepositional verb structures further supporting the speaker's perspective. Based on these findings Wasow concludes that HNPS is correlated with the speaker's preference for late commitment thereby demonstrating how speaker performance preference can influence word order.
While the dominant views of grammar are largely oriented towards competence, many, including Chomsky himself, have argued that a complete model of grammar should be able to account for performance data. But while Chomsky argues that competence should be studied first, thereby allowing further study of performance, some systems, such as constraint grammars are built with performance as a starting point (comprehension, in the case of constraint grammars While traditional models of generative grammar have had a great deal of success in describing the structure of languages, they have been less successful in describing how language is interpreted in real situations. For example, traditional grammar describes a sentence as having an "underlying structure" which is different from the "surface structure" which speakers actually produce. In a real conversation, however, a listener interprets the meaning of a sentence in real time, as the surface structure goes by.[16] This kind of on-line processing, which accounts for phenomena such as finishing another person's sentence, and starting a sentence without knowing how it is going to finish, is not directly accounted for in traditional generative models of grammar.[16] Several alternative grammar models exist which may be better able to capture this surface-based aspect of linguistic performance, includingConstraint Grammar, Lexical Functional Grammar, and Head-driven phrase structure grammar.
Errors in linguistic performance not only occur in children newly acquiring their native language, second language learners, those with a disability or an acquired brain injury but among competent speakers as well. Types of performance errors that will be of focus here are those that involve errors in syntax, other types of errors can occur in the phonological, semantic features of words, for further information see speech errors. Phonological and semantic errors can be due to the repetition of words, mispronunciations, limitations in verbal working memory, and length of the utterance.[17] Slips of the tongue are most common in spoken languages and occur when the speaker either: says something they did not mean to; produces the incorrect order of sounds or words; or uses the incorrect word.[18] Other instances of errors in linguistic performance are slips of the hand in signed languages, slips of the ear which are errors in comprehension of utterances and slips of the pen which occur while writing. Errors of linguistic performance are perceived by both the speaker and the listener and can therefore have many interpretations depending on the persons judgement and the context in which the sentence was spoken.[19]
It is proposed that there is a close relation between the linguistic units of grammar and the psychological units of speech which implies that there is a relation between linguistic rules and the psychological processes that create utterances.[20] Errors in performance can occur at any level of these psychological processes. Lise Menn proposes that there are five levels of processing in speech production, each with its own possible error that could occur.[18] According to the proposed speech processing structure by Menn an error in the syntactic properties of an utterance occurs at the positional level.
Another proposal for the levels of speech processing is made by Willem J. M. Levelt to be structured as so:[21]
Levelt (1993) states that we as speakers are unaware of most of these levels of performance such as articulation, which includes the movement and placement of the articulators, the formulation of the utterance which includes the words selected and their pronunciation and the rules which must be followed for the utterance to be grammatical. The levels speakers are consciously aware is the intent of the message which occurs at the level of conceptualization and then again at self-monitoring which is when the speaker would become aware of any errors that may have occurred and correct themselves.[21]
One type of slip of the tongue which cause an error in the syntax of the utterance are called transformational errors. Transformational errors are a mental operation proposed by Chomsky in his Transformational Hypothesis and it has three parts which errors in performance can occur. These transformations are applied at the level of the underlying structures and predict the ways in which an error can occur.[20]
Structural Analysiserrors can occur due to the application of (a) the rule misanalyzing the tense marker causing the rule to apply incorrectly, (b) the rule not being applied when it should or (c) a rule being applied when it should not.
This example from Fromkin (1980) demonstrates a rule misanalyzing the tense marker and for subject-auxiliary inversion to be incorrectly applied. The subject-auxiliary inversion is misanalyzed as to which structure it applies, applying without the verb be in the tense as it moves to the C position. This causes "do-support" to occur and the verb to lack tense causing the syntactic error.
6a. Error: Why do you be an oaf sometimes? 6b. Target: Why are you an oaf sometimes?