Chapter 5 Vowel Harmony in Deori
5.4 Optimality Theory
5.4.1 A TR harmony in Deori: an OT account
The descriptive facts of Deori vowel harmony discussed so far highlights that vowel agreement in Deori necessitates a constraint which requires the marked vowels [e] and [o] to appear to the left of the [+high +ATR] /i/ and /u/ vowels and not otherwise, similar to Assamese. In this section, it will be shown that the markedness and the faithfulness constraint that accounts for the Assamese vowel harmony pattern as reported in Mahanta (2007) is also active in Deori.
Following Mahanta (2007), a step by step discussion of the markedness and faithfulness constraints accounting for vowel harmony process and its appropriateness in taking care of Deori vowel harmony is discussed below.
In OT, the markedness and the faithfulness constraint which accounts for the assimilatory process are AGREE[F] and IDENT[F] respectively.
Markedness constraint (56) AGREE[F]
Adjacent segments have the same value for the feature.
Faithfulness constraint (57) IDENT[F]
Input-Output segments have the same value for the feature [F]
To result in the assimilatory process the markedness constraint AGREE[F] has to be ranked higher than the faithfulness constraint IDENT[F]. A schematic tableau below shows that the ranking of the markedness constraint over the faithfulness constraint is essential to capture assimilation in OT.
(58) Schematic tableau
I:[-F][+F] AGREE[F] IDENT[F]
a. [-F][+F] *!
b. [+F][+F] *
This hierarchical ranking of the markedness and faithfulness constraint can capture the vowel harmony in Deori which is shown in a schematic tableau in (59) below, considering a real example from Deori. The following tableau shows that optimal output is (b) which satisfies the high ranked markedness constraint AGREE[F] thereby violating the low ranked faithfulness constraint IDENT[F].
(59) Vowel harmony tableau
I: /bɔ/+/ɹi/ AGREE[F] IDENT[F]
a. [bɔɹi] *!
b. [boɹi] *
The above tableau shows that the verbal root /bɔ/ agrees with the following high vowel /ɹi/ in the suffix and surfaces as /boɹi/ which satisfies the high ranked constraint AGREE[F]. Tableau (59) further shows that the ranking of Markedness » Faithfulness is necessary to account for the assimilatory process in OT. However, in tableau (58) and (59) there is also a possibility of assimilation to the [-F] feature which would result in [-F][-F] featural composition which involves progressive assimilation. The assimilation to the [-F] feature would generate an ill- formed output such as */bɔɹɪ/ which is not attested in Deori. In Deori, it is only [+high +ATR] feature which triggers vowel harmony regressively on the preceding vowel. Moreover, [+high - ATR] vowels /ɪ/ and /ʊ/ are not attested in Deori67. Hence, AGREE[F] is not capable of accounting for the assimilation process in a language where spreading is unidirectional. The limitation of the AGREE[F] constraint to capture vowel harmony process which is strictly unidirectional is postulated by Mahanta 2007 as follows: “The symmetrical nature of AGREE[F] prohibits the right results in strictly directional systems. AGREE is capable of showing the right result only when unbounded iterative assimilation is the predicted form. AGREE fails while evaluating input candidates like [-ATR][+ATR][-ATR], where the desired output is one with regressive harmony and not total agreements of the flanking [-ATR] vowels on both sides” p. 36 . Thus the behavior
67 owever, /ʊ/ is attested in Assamese vowel inventory.
of AGREE is disentangled “from its inherently asymmetric nature to a more specific constraint which identifies the marked sequence of features” Mahanta, 2007, p. 37 and represented in two sub-constraints which would result in regressive or progressive directionality instead of total assimilation. The sub-constraints as discussed in Mahanta (2007) are presented below:
(60) Sequential markedness constraints
*[+F][-F] - Assign a violation mark to [-F] segments preceded by [+F] segments
*[-F][+F] - Assign a violation mark to [+F] segments preceded by [-F] segments
The sequential markedness constraint *[-F][+F] is suitable to account for the regressive assimilatory process in which the occurrence of the feature [-F] followed by a feature value [+F]
is marked in a language such as Assamese as postulated by Mahanta (2007). Since Deori resembles the Assamese vowel harmony pattern the sequential markedness constraint *[-F][+F]
can also account for the regressive vowel harmony pattern in Deori. In Deori, there is no word sequence such as [+ATR][+ATR][-ATR] which would have been good test words for the directionality of assimilation. Nevertheless, the marked sequence such as [-ATR][+ATR] and unmarked sequence such as [+ATR][+ATR] and [+ATR][-ATR] in Deori is sufficient to validate the directionality in the language as regressive. Following Mahanta (2007), it is argued that in Deori the assimilatory agreement is the outcome of contextual neutralization and this instance of contextual neutralization is driven by a sequential markedness constraint which prohibits the occurrence of a marked feature [-F] when followed by a [+F] feature, but not vice-versa. The sequence which requires to be prohibited in Deori is *[-ATR][+ATR]. The sequential markedness constraint which drives harmony in Deori is discussed below:
(61) *[-ATR][+ATR]
Assign a violation mark to a [-ATR] vowel followed by a [+ATR] vowel.
The constraint *[-ATR][+ATR] penalizes the occurrence of [-ATR] vowels when followed by [+ATR] vowels. For instance, when a verb root undergoes inflection /bᴐ/+/ɹi/ “beat” the output
*/bᴐri/ violates the constraint *[-ATR][+ATR]. On the other hand, the output /bori/ satisfies the constraint *[-ATR][+ATR].
Apart from the markedness constraint which bans a marked [-ATR][+ATR] sequence in Deori, a faithfulness constraint is also required which will penalize any deviation of the surface form
(output) from its lexical form (input). Faithfulness constraint evaluates the identity of correspondent elements. The IDENT family of constraints, initially proposed as below in McCarthy and Prince (1995), relate corresponding input and output features of a segment:
(62) IDENT (F)
Let α be a segment in 1 and β be any correspondent of α in 2. If α is [γF], then β is [γF].
“Correspondent segments are identical in feature F” .
Taking the IDENT (F) constraint into consideration to account for [-ATR] harmony domains, similar to Assamese, it can be shown thatthe underlying feature value of the [-ATR]vowels are retained in the absence of harmony-inducing high vowels in Deori. Thus, IDENT [ATR]constraint is taken into account which would preserve the underlying [-ATR] feature in absence of the following [+high+ATR] vowels. Following Mahanta (2007), the IDENT [ATR] constraint which preserves the harmonic value of [-high -ATR] vowels, if not followed by triggering high vowels, is discussed below:
(63) IDENT [ATR]
A segment in the output and its correspondent in the input must have identical specifications for [ATR].
The faithfulness constraint IDENT [ATR] will be ranked lower than the sequential markedness constraint *[-ATR][+ATR] because faithfulness constraint will prevent the alternation of /ε/ and /ɔ/ to [e] and [o] as it requires identical input and output form. Therefore, *[-ATR][+ATR] is ranked above IDENT [ATR] which will yield the well-formed output.
In this section, the constraints resulting in the assimilatory process in Deori are discussed. In the next subsections, the operation of the harmony-driven constraint *[-ATR][+ATR] vis-à-vis other constraints enforcing regressive harmony will be discussed in detail with respective tableau.