@article { author = {Sahragard, Rahman and Rahimian, Jalal and Rahmani Anaraki, Reza}, title = {The effects of changing the deletion direction and deletion ratio on the validity and reliability of the C-test}, journal = {Teaching English Language}, volume = {3}, number = {1}, pages = {23-52}, year = {2008}, publisher = {Teaching English Language and Literature Society of Iran (TELLSI)}, issn = {2538-5488}, eissn = {2538-547X}, doi = {10.22132/tel.2008.128580}, abstract = { 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.}, keywords = {C-test,deletion direction,deletion ratio,Validity,Reliability}, title_fa = {اثر}, abstract_fa = {اثر}, keywords_fa = {آزمون سی}, url = {http://www.teljournal.org/article_128580.html}, eprint = {http://www.teljournal.org/article_128580_355360f11ac6e20eb32cc6a2d676cf68.pdf} }