An acoustic study of Dimasa tones

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An acoustic study of Dimasa tones

• Priyankoo Sarmah and Caroline Wiltshire
• University of Florida
• priyanku_at_ufl.edu
• wiltshir_at_ufl.edu

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The Dimasa Language

• Tibeto-Burman Language of the Bodo-Garo family.
• Spoken by 88,543 people in Assam and Nagaland.
• (1991 Indian census report)
• RCILTS, IIT Guwahati (http//www.iitg.ernet.in/rci
  lts/dimasa.htm )
• 2 tones High, Unmarked Level
• Singha (2003)
• 3 tones High, Low and Unmarked Level

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This study

• How many tones are there in Dimasa?
• What are the acoustic properties of Dimasa tones?
• How do tones operate in monosyllables and
  disyllables?

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Methodology Wordlist and speakers

• A list of segmentally homophonic words was
  constructed using data from a native speaker of
  Dimasa.
• The words were arranged in random order in the
  list.
• 10 native speakers of Dimasa (5 male, 5 female)
  were asked to produce the words in a sentence
  frame.
• ang X thiba
• Each word was repeated four times by the
  speakers.
• Only the first three iterations were included in
  analysis to avoid listing effect.

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Methodology Recording the data

• Recorder Marantz PMD660 solid state
• Sampling frequency 48 Khz
• Microphone Audio-Technica AT4041
• Storage HP compact flash card

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Methodology Analyzing the data

• Praat v.4.5.04
• Measure 1 Track the pitch on the TBU at every
  2 of the length of the TBU
• Measure 2 The initiation point of the pitch on
  TBU
• Measure 3 20ms after initiation of the pitch on
  TBU

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Methodology Analyzing the data

• Measure 1 is taken to track the pitch of the TBU
  in detail.
• Automatic pitch tracking of Praat is not detailed
  enough.
• It also normalizes the length as values are
  derived.
• Measure 2 and Measure 3 are taken to see if and
  to what extent the consonant in the onset affects
  the pitch of the TBU.

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Methodology Analyzing the data

• Measure 1 Every 2 of the pitch on TBU 50
  points

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Methodology Analyzing the data

• Measure 2 Point of initiation of the pitch on
  the TBU (Pi)
• Measure 3 20ms after the point of initiation
  (Pi20)

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Methodology

• For all the measurements specific scripts were
  written.
• The script were run on 103 underived words of
  Dimasa.
• The 103 words included monosyllabic and
  polysyllabic words.

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Measure 2 and 3

• Pi and Pi20 are compared statistically
• A standard t-test (plt0.05) is conducted on the
  data.
• Grouped by the onset consonant.

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Results Measure 2 and 3
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Results Measure 2 and 3

• ph, kh, b, d, g, dz, h, l, r,
  s, sh, z
• Showed significant effect on the following
  pitch.
• m and w did not show significant effect on
  the following pitch.
• Pi (Pi20) showed that
• ph, kh, b, d, dz, h, l, s, sh,
  z raises the following pitch.
• r depresses the following pitch.

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Results Measure 1

• Pitch points were calculated on 50 points across
  the pitch of each TBU (every 2)
• These 50 points were replotted on a graph to
  reconstruct the pitch track.

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Results Measure 1

• Initial examination of data set in Singha (2003)
• thi speak
• thi to die
• thi blood
• lai page
• lai easy
• lai wish
• maithai year
• maithai crop
• maithai source

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Results Measure 1

• Demonstrates tonal distinction in segmentally
  homogeneous pairs.

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Results Measure 1
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Results Measure 1

• /maithai/ crop

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Results Measure 1

• /maithai/ source

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Results Measure 1

• /maithai/ year

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Results Measure 1

• Compared to Singha (2003)
• ? /thi/ shows evidence for three distinct tones
• ? /lai/ does not show evidence for three tones
• ? /maithai/ does not show evidence for three
  tones.

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Results Measure 1

• Another interesting set
• bai to break
• bai to cross
• bai to dance
• bai to order
• bai to ship
• bai to spin

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Results Measure 1
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Results Measure 1

• In most of the cases

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Results Measure 1

• Tones
• Dimasa has three lexical tones
• A high tone (rising)
• A level mid tone
• A low tone (falling)

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Bisyllables in Dimasa

• No mention in Singha (2003)
• Bodo-Garo languages primarily show tone
  assignment on only one syllable.
• (Joseph and Burling, 2001 Sarmah 2003)

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Bisyllables in Dimasa

• goron company
• goron to confuse
• miya bamboo shoot
• miya male person
• miya yesterday

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Results Bisyllables

• /goron/ company

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Results Bisyllables

• /goron/ confuse

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miya male person
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miya bamboo shoot
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miya yesterday
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Results Bisyllables

• Tone assigned only on the second syllable.
• Similar phenomenon to Bodo (Sarmah 2003)
• The first syllable is assigned a mid level tone.
• Similar phenomenon in other 9 sets of bisyllables
  we examined.

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Summary of results

• Significant consonantal effects on pitch
• 3 tones in Dimasa
• A high tone (rising)
• A level mid tone
• A low tone (falling)
• A mono/disyllabic word can have one and only one
  tone assigned to it.

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• Association of glottal stops with high tones.
• Trisyllabic words.
• A perception test
• More data

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References

• Joseph, U. V., and Burling, Robbins. 2001. Tone
  correspondences among the Bodo Languages.
  Linguistics of the Tibeto-Burman Area. 24.2
  41-55.
• Sarmah, Priyankoo. 2003. Some Aspects of the
  Tonal Phonology of Bodo. M.Phil. dissertation,
  CIEFL, Hyderabad, India.
• Singha, Dhiren. 2003. The Phonology Morphology
  of Dimasa. M.A. dissertation, Assam University,
  Silchar, Assam

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Acknowledgment

• Mr. Uttam Bathari, Asst. Director, ICHR,
  Guwahati, Assam.
• University of Florida, Graduate Research
  Program.
• and

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Acknowledgment

• The Dimasa Students Association
• Guwahati

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This presentation is available

• By email priyanku_at_ufl.edu
• Online http//plaza.ufl.edu/priyanku/neils.ppt