Research Article

Psychometric Function Characteristics of Time- Compressed Persian Words


Background and Aim: The psychometric function characteristics (e.g. threshold and slope) of the time-compressed words have not been investigated in previous studies to compile psychometrically homogeneous word lists. Therefore, this study aimed to investigate psychometric function characteristics of monosyllabic time-compressed Persian words to develop psychometrically equivalent time-compressed word lists.
Methods: Two hundred most common monosyllabic words in Persian language were timecompressed at a rate of 40%-85% and presented to 21 participants with normal hearing at a fixed intensity level. The threshold and slope of the psychometric function for all words were determined using the logistic regression. The compression ratio (CR) for 5%-95% correct recognition was predicted based on the psychometric function fitted to the measured correct recognition score.
Results: Mean CR 50% of the words was in a range of 53%-78%. The mean CR 50% and slope were not significantly different between consonant-vowel-consonant and consonantvowel-consonant-consonant words. The predicted CR for 5%-95% correct recognition varied from 61.5% to 88.4%. The final result was two 50-word lists of monosyllabic words with the same mean threshold and slope.
Conclusion: Persian time-compressed monosyllabic words have different CR 50% and slope that may interact with their intelligibility.

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IssueVol 31 No 3 (2022) QRcode
SectionResearch Article(s)
Time compression intelligibility psychometric function Persian monosyllabic words

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Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
How to Cite
Moosapour Bardsiri M, Mahdavi ME. Psychometric Function Characteristics of Time- Compressed Persian Words. Aud Vestib Res. 2022;31(3):175-179.