國中生物科適性測驗的建構歷程--IRT理論的應用

Computerized Adaptive Testing of Junior High School Biology--Applications of Item Response Theory

本研究的主要目的在應用IRT理論建構一個國中生物科的電腦化適性測驗。基本上電腦化適性測驗必須應用下列五個步驟方能達成準確評量學生真實能力的目的：（1）題庫建立及施測；（2）參數連結；（3）IRT試題分析；（4）適性測驗程式設計及流程；（5）效度評估研究。本研究建構之題庫包含近一千個有效試題，施測逾3000樣本，以迴歸方式作參數連結，應用IRT單參數模式選題及評估學生能力，並以學生學業成續為效標，驗證其效度及分析再測信度。本研究計畫後續將以學生基本學力測驗為效標進行預測效度分析，並探討IRT雙參數及三參數模式的應用。

The purpose of this study was to construct a computerized adaptive test for junior high biology by applying item response theory. Five procedures were suggested for a successful application of latent trait theory in the computerized adaptive testing : (1) item banking and testing ; (2) test equating : (3) item response theory analysis : (4) the programming and procedures of computerized adaptive testing ; and (5) the evaluation of test validity. The item bank of the computerized adaptive test for junior high biology consisted of about a thousand valid items. More than three thousand samples in total were selected for item calibration. The parameters of item difficulty and item discrimination for each test were equated using anchor tests by regression methods. One-parameter tailored testing procedure was applied to the selection of next item tested and estimation of examinee’s latent trait. Classical test scores were compared with the latent trait of the computerized adaptive test for the validity. Test-retest correlation was analyzed for the test reliability. It is suggested that more criteria should be considered to validate computerized adaptive testing. In addition， two-parameter and three-parameter tailored testing procedures will be discussed in the near future.