Summary of the Features of the NSP Corpus

  • The corpus includes speech from 60 talkers representing six regional varieties of American English.
  • Talkers are balanced for gender and regional dialect, with five males and five females from each region.
  • Talkers are relatively homogeneous with respect to other demographic variables, including age, ethnicity, linguistic experience, level of education, and socioeconomic status.
  • Speech materials from each talker include isolated words, sentences, passages, and interview speech.
  • High-quality digital recordings were obtained from each talker in a sound-attenuated booth.

The corpus is fully described in: Clopper, C. G., & Pisoni, D. B. (2006). The Nationwide Speech Project: A new corpus of American English dialects. Speech Communication, 48, 633-644.

Talkers

The talkers included in the NSP corpus were five male and five female lifetime residents of six dialect regions in the United States: New England, Mid-Atlantic, North, Midland, South, and West. These regions are based on the dialect regions described by Labov, Ash, and Boberg (2006). The hometowns of the 60 NSP talkers are shown in the map below. Dark dots indicate male talkers. Light dots indicate female talkers.


Apart from gender and regional dialect, the talkers in the NSP corpus were fairly homogeneous: they were all white native speakers of American English with native English-speaking parents who ranged in age from 18-25 years old.

Materials

A range of speech materials was obtained from each talker, including isolated words, sentences, passages, and interview speech. The materials include:

  • hVd Words (N=10), such as heed, hid, head
  • CVC Words (N=76), such as mice, dome, bait
  • Multisyllabic Words (N=112), such as alfalfa, nectarine (from Carter & Clopper, 2002)
  • High Predictability Sentences (N=102), such as Ruth had a necklace of glass beads and The swimmer dove into the pool (from Kalikow, Stevens, & Elliott, 1977)
  • Low Predictability Sentences (N=52), such as Tom has been discussing the beads and She might consider the pool (from Kalikow, Stevens, & Elliott, 1977)
  • Anomalous Sentences (N=52), such as Bill knew a can of maple beads and The jar swept up the pool (see Clopper et al., 2002)
  • Rainbow Passage (Fairbanks, 1940)
  • Goldilocks Passage (Stockwell, 2002)
  • Interview Speech (5 minutes) on topics such as hometown, hobbies, travel experiences
  • Targeted Interview Speech to elicit target words (N=10), such as sleep, shoes, math, in spontaneous speech 

All of the recordings were made in a sound-attenuated booth. Using homegrown software, the utterances were recorded in individual .aiff sound files on a Macintosh laptop at a sampling rate of 44.1 kHz with 16-bit encoding.

References

Carter, A. K., & Clopper, C. G. (2002). Prosodic effects on word reduction. Language and Speech, 45, 321-353.

Clopper, C. G., Carter, A. K., Dillon, C. M., Hernandez, L. R., Pisoni, D. B., Clarke, C. M., Harnsberger, J. D., & Herman, R. (2002). The Indiana Speech Project: An overview of the development of a multi-talker multi-dialect speech corpus. Research on Spoken Language Processing Progress Report No. 25 (pp. 367-380). Bloomington, IN: Speech Research Laboratory, Indiana University.

Fairbanks, G. (1940). Voice and Articulation Drillbook. New York: Harper.

Kalikow, D. N., Stevens, K. N., & Elliott, L. L. (1977). Development of a test of speech intelligibility in noise using sentence materials with controlled word predictability. Journal of the Acoustical Society of America, 61, 1337-1351.

Labov, W., Ash, S., & Boberg, C. (2006). Atlas of North American English. Berlin: Mouton de Gruyter.

Stockwell, P. (2002). Sociolinguistics: A Resource Book for Students. London: Routledge.