The effects of changing the deletion direction and deletion ratio on the validity and reliability of the C-test
Autor: | Rahman Sahragard, Jalal Rahimian, Reza Rahmani Anaraki |
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Jazyk: | angličtina |
Rok vydání: | 2008 |
Předmět: | |
Zdroj: | Teaching English Language, Vol 3, Iss 1, Pp 23-52 (2008) |
Druh dokumentu: | article |
ISSN: | 2538-5488 2538-547X |
DOI: | 10.22132/tel.2008.128580 |
Popis: | This study looks at the effects of changing the deletion direction and ratio on the validity and reliability of the C-test. For this purpose, a cluster sampling procedure was used to select 324 English students with different levels of proficiency. The subjects were then randomly assigned to three experimental groups. Each group took a TOEFL test and a C-test version. The three C-test versions were all based on the same texts. Immediately after completing the C-test, subjects received a ten-item questionnaire about issues such as face validity, suitability, and possible functions of the C-test. The findings indicated that changing the deletion ratio from 2 to 3 can result in an easier C-test with a higher discrimination power and a better criterion-related validity. On the other hand, changing the deletion direction (from right to left) can result in a more difficult C-test with a lower discrimination power and a worse concurrent validity –a C-test which might be a completely different test that measures a different construct. However, the changes to the deletion technique probably do not result in any changes to the reliability. |
Databáze: | Directory of Open Access Journals |
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