1. Anne Fabricius, Roskilde University Dominic Watt, University of York and J.P French Associates

2.  Background to the paper  Aim of the research  Introducing the S-centroid anchor method  Application to some vowel data from British English (SSBE/Modern RP)  Discussion and further implications 2Angle configurations and the S-centroid

3.  Quantitative methods in a quantitative discipline  The art and science of vowel change (Labov 1994)  Earlier work this study is based on  Watt and Fabricius S-centroid method (Watt and Fabricius 2002)  TRAP/STRUT rotation in RP (Fabricius 2007) and angle methods using vowel juxtapositions  Testing normalisation methods (Fabricius, Watt and Johnson 2009) for geometrically-related properties  Here: Combining the two (normalization and modelling changing vowel loci distributions around the centroid) 3Angle configurations and the S-centroid

4. Adapted from Fabricius 2007: 300 4Angle configurations and the S-centroid

5. Flynn 2010: slide 16 For variety-specific modifications of the Watt and Fabricius S-centroid method, see also Durian, forthcoming and Bigham 2008. mW&F uses F1 of [a] only 5Angle configurations and the S-centroid

6.  In geometry, the centroid, geometric center, or barycenter of a plane figure or two-dimensional shape X is the intersection of all straight lines that divide X into two parts of equal moment about the line. Informally, it is the "average" (arithmetic mean) of all points of X.  (From Wikipedia) 6Angle configurations and the S-centroid

7.  Peeters 2004 7Angle configurations and the S-centroid

8.  To present the method  To investigate the methodological advantages for sociophonetics of representing relative planar locations as vectors vis à vis a pre-defined geometrical centroid of the vowel space  To ask whether this supports other arguments in favour of a centroid-based normalisation method? (in the spirit of Fabricius, Watt and Johnson 2009) 8Angle configurations and the S-centroid

9.  Make no claims here about the centroid’s perceptual significance (although the concept does feature in some perception/normalisation research, eg Deterding 1990)  Used here as a geometric point to investigate and illustrate properties of vowel distributions in F1/F2 space 9Angle configurations and the S-centroid

10.  Effect of speech disorders on the vowel space and distance of vowels from the centroid (e.g. in stuttering: Blomgren, Robb and Chen 1998)  Pickering 1986 formalised peripherality measured as dispersion from a centroid, context speech perception research  Hyper- and hypo-articulation, ie clear and indistinct speech: (Lindblom 1990, 1996, Ferguson & Kewley- Port, 2002; Picheny, Durlach, & Braida, 1986)  Whiteside 2001; NB definition of centroid used here differs from this presentation since axes are derived differently (using Bark differences) 10Angle configurations and the S-centroid

11.  R-algorithm developed by Daniel Ezra Johnson after an idea by Anne Fabricius  Available here (The Modern RP Page) 11Angle configurations and the S-centroid

12. 0°0° 180° -180° 90° -90° S-centroid point F1 F2 12Angle configurations and the S-centroid

13. 0°0° 180° -180° 90° -90° S-centroid point F1 F2 i u a 13Angle configurations and the S-centroid

14. 14Angle configurations and the S-centroid

15.  Documenting changes by measurements in degrees vis a vis a stable point, rather than eyeball judgments of relative placement  Could also be used in combination with Euclidean/Cartesian distances (as in Fabricius 2007, Richards, Haddican and Foulkes 2009)  Quantification enables further statistical testing  Has potential applications in determining the nature of centre versus periphery in the vowel space (Labov 1994) in a more reproducible way 15Angle configurations and the S-centroid

16.  RP generational vowel data from Hawkins and Midgley 2005 and Moreiras 2006, plus Fabricius 2009  using R script devised by Daniel Ezra Johnson  This example: short vowel system with lines connecting average vowel loci 16Angle configurations and the S-centroid

17. 17 Female speakers, 1998 cohort Angle configurations and the S-centroid (Data from Fabricius 2009)

18. 18 Female speakers, 2008 cohort Angle configurations and the S-centroid (Data from Fabricius 2009)

19. 19 Male speakers, 1998 cohort (Data from Fabricius 2009) Angle configurations and the S-centroid

20. 20 Male speakers, 2008 cohort (Data from Fabricius 2009) Angle configurations and the S-centroid

21.  To make these types of configurations more easily comparable  By using the S-centroid point as anchor  deriving angles vis-à-vis the centroid point  The S-centroid point is common to ALL speakers in the sample since they are all normalised using the W&F (or mW&F) method  Advantage: the S-centroid does not move over time Angle configurations and the S-centroid21

22. Angle configurations and the S-centroid22 Illustration

23. Angle configurations and the S-centroid23 FLEECE stable over time: OM, OF: older generation; YM, YF: younger generation

24. 0°0° 180° -180° 90° -90° S-centroid point F1 F2 24Angle configurations and the S-centroid FLEECE

25. Angle configurations and the S-centroid25 FOOT moving over time

26. 0°0° 180° -180° 90° -90° S-centroid point F1 F2 26Angle configurations and the S-centroid FOOT, older FOOT, YF3

27. Angle configurations and the S-centroid27 LOT variability, mostly among younger female speakers

28. Angle configurations and the S-centroid28 STRUT in this perspective also variable; nb Reduced scale here

29.  What are the methodological advantages to representing relative planar locations as vectors vis a vis the centroid location of the vowel space?  Quantifiability, reproducibility, visual evidence backing auditory perceptions  Does this argue for the advantages of a centroid-point based normalisation method?  Yes, and the method could also be adapted to work from the centroid-based Lobanov normalisation algorithm.  But Lobanov’s normalisation method is in some cases too powerful (close to a standard statistical normalisation technique) and performs less well overall (in several testing parameters) than mW&F in Flynn’s comparison of 20 normalisation algorithms (Flynn 2010) 29Angle configurations and the S-centroid

30.  Method offered here as an aid to the sociophonetic community  The illustrative chart template will also be available online ( MS Excel.crtx file)  NB A Euclidean distance metric could be included as well  R-code will be available and can be adjusted 30Angle configurations and the S-centroid

31.  Bigham, Douglas. 2008. Dialect contact and accommodation among emerging adults in a university setting. Ph.D. thesis. The University of Texas at Austin.  Deterding, David. 1990. Speaker Normalisation for Automatic Speech Recognition, Unpublished PhD Thesis, Cambridge University.  Fabricius, Anne. 2007. Variation and change in the TRAP and STRUT vowels of RP: a real time comparison of five acoustic data sets. JIPA 37:3: 293-320.  Fabricius, Anne. 2009. Short vowels in real time: TRAP, STRUT and FOOT in the South of England. Paper presented at ICLaVE 5, Copenhagen. June 27 th 2009. (www.ruc.dk/~fabri )www.ruc.dk/~fabri  Fabricius, Anne H., Dominic Watt and Daniel Ezra Johnson. 2009. A comparison of three speaker-intrinsic vowel formant frequency normalization algorithms for sociophonetics. Language Variation and Change, 21,3:1-23.  Flynn, Nicholas. 2010. Comparing vowel formant normalisation procedures. Talk given at York Postgraduate Mini-conference, June 10th, 2010.  Hawkins, Sarah and Jonathan Midgley. 2005. Formant frequencies of RP monophthongs in four age groups of speakers. JIPA 30: 63-78.  Labov, William. 1994. Principles of Linguistic Change volume 1: Internal Factors. Oxford: Blackwell. 31Angle configurations and the S-centroid

32.  Lindblom, B. 1990: Explaining phonetic variation: A sketch of the H&H theory, in Speech Production and Speech Modeling, edited by W. J. Hardcastle and A. Marchal. Kluwer Academic, Netherlands, pp. 403–439.  Lindblom, B. 1996: Role of articulation in speech perception: Clues from production. Journal of the Acoustical Society of America, 99, 1683–1692.  Moreiras, C. 2006. An acoustic study of vowel change in female adult speakers of RP. Unpublished undergraduate dissertation, University College London.  Peeters, Geoffroy. 2003. A large set of audio features for sound description (similarity and classification) in the CUIDADO project. http://recherche.ircam.fr/equipes/analyse- synthese/peeters/ARTICLES/Peeters_2003_cuidadoaudiofeatures.pdf http://recherche.ircam.fr/equipes/analyse- synthese/peeters/ARTICLES/Peeters_2003_cuidadoaudiofeatures.pdf  Pickering, J.B. 1986. Auditory vowel formant variability. Unpublished doctoral dissertation, Oxford University.  Richards, Hazel, Bill Haddican and Paul Foulkes. 2009. Exhibiting standards in the FACE of dialect levelling. Paper presented at ICLaVE 5, Copenhagen, June 2009.  Watt, Dominic and Anne Fabricius. 2002. Evaluation of a technique for improving the mapping of multiple speakers’ vowel spaces in the F1-F2 plane. Leeds Working papers in Linguistics and Phonetics. 9: 159-173. Angle configurations and the S-centroid32

33.  Daniel Ezra Johnson  Tyler Kendall  Nicholas Flynn  Nicolai Pharao Angle configurations and the S-centroid33