چکیده:
In English as a Second Language Teaching and Testing situations, it is common to infer about learners’ reading ability based on his or her total score on a reading test. This assumes the unidimensional and reproducible nature of reading items. However, few researches have been conducted to probe the issue through psychometric analyses. In the present study, the IELTS exemplar module C (1994) was administered to 503 Iranian students of various reading comprehension ability levels. Both the deterministic and probabilistic psychometric models of unidimensionality were employed to examine the plausible existence of implicational scaling among reading items in the mentioned reading test. Based on the results, it was concluded that the reading data in this study did not show a deterministic unidimensional scale (Guttman scaling); rather, it revealed a probabilistic one (Rasch model). As the person map of the measures failed to show a meaningful hierarchical order for the items, these results call into question the assumption of implicational scaling that is normally practiced in scoring reading items.
خلاصه ماشینی:
"Organization of the IELTS Exemplar Theoretical Framework or hierarchical level Sechtieoneostf oNfuitmebmesr Item taxonomical ability 1 2 3 4 Passage 1 13 V1 to V4 Factual questions X V5 Scanning X V6 Conclusion based on the X word "gradually" V7 Metadiscourse "unlike" X V8 Meta discourse "unlike" X V9 Conclusion based on the X word "originally" V10 to V13 Syntactical meaning X Passage 2 7 V14 to V20 Main idea X Task 1 Passage 2 8 V 21 to V28 Summary X Task 2 Passage 3 8 V 29 Understanding cohesive X mark V 30 Understanding cause and X X effect relation V 31 to V32 Detail of information X V 33 to V36 Transcoding X Note that Level 1 is related to scanning or searching for information Level 2 is syntactical information and is not related to the relationships between sentences Level 3 is related to the whole paragraph and mostly conclusion Level 4 is related to the whole text and is summary through text or graph Procedure Once the test was administered to the focal students, the responses were coded into a data base and analyzed for item and test calibration.
The results confirm that theoretical abilities must be represented at least in a three dimensional space: the content of the academic or professional matter (organized in topics, subjects, chapters, & areas), the difficulty of the items (from easy to hard) and the cognition process of the persons (from simple to complex or from low level to higher order)."