Percent Phones Correct (PPC)

The PPC analysis will calculate the percent phones/consonants/vowels correct in the sampled data.

Data Preparation

Session data is queried by word for each IPA Target and IPA Actual tuple. Proper syllabification and phone alignment is required for accurate results. All participants should have unique names/identification numbers and a speaker should be assigned to all records.

Parameters

Figure 1. Percent Phones Correct Parameters
The PPC report can be restricted to different sets of phones. Several pre-defined sets have been defined and are available by using the radio buttons displayed in the PPC form (see below.) The following pre-defined report types are available:
  1. Percent phones correct - all phones.
  2. Percent consonants correct - all consonants (i.e., PCC)
  3. Percent vowels correct
  4. Percent singleton consonants correct - singleton consonants.
  5. Percent cluster consonants correct - cluster consonants. There are three report sub-types available when this option is selected:
    1. All clusters
    2. Tautosyllabic clusters
    3. Heterosyllabic clusters
  6. Percent onset consonants correct. There are three report sub-types available when this option is selected:
    1. All onsets
    2. Singleton onsets
    3. Cluster onsets
  7. Percent coda consonants correct. There are three report sub-types available when this option is selected:
    1. All codas
    2. Singleton codas
    3. Cluster codas
  8. Percent nucleus phones correct. There are three report sub-types available when this option is selected:
    1. All nuclei
    2. Monophthongs
    3. Complex vocoids
  9. Percent correct (custom)

When 'Percent correct (custom)' is selected a custom Phonex expression may be entered to create a custom phone set. See Example Phones Queries for some useful examples.

PPC Calculation

PPC is calculated using the following equation:

If requested a second PPC column which does not include epenthesis may be added to the report. The column will be named 'PPC (NoEpen)'.

Report Outline

A sample table of contents is displayed below. Bold level elements are section headers while italic items are tables.

  • Percent Phones Correct (PPC)

    • Summary

      • All Participants

      • IPA Patterns

    • Participant 1
      • Summary
      • IPA Patterns
    • … (for each selected participant)

    • Listing (All Results)

References

  • Shriberg, L. D., & Kwiatkowski, J. (1982). Phonological disorders III : A procedure for assessing severity of involvement. Journal of Speech and Hearing Disorders, 47, 256–270.
  • Shriberg, L. D., Austin, D., Lewis, B. A., McSweeny, J. L., & Wilson, D. L. (1997). The Percentage of Consonants Correct (PCC) Metric: Extensions and Reliability Data. Journal of Speech, Language, and Hearing Research, 40(4), 708–722.Today