摘要 本研究主要目的是以王淑卿（2005）三年級數學領域能力指標為基礎之題 庫，匯集測驗理論、曝光率控制與電腦網際網路等相關技術，建置一套三年級數 學科能力指標為基礎的電腦適性測驗評量系統。 在研究方法上，結合試題反應理論和a-鄰近選題法之電腦適性測驗評量模 式，在適性測驗系統施測時，即進行試題曝光率的控制以及受試者能力值的精確 估計，並將所有學生的答題歷程記錄彙整成為曝光率控制的數據。 研究結果發現： 一、 以試題反應理論為基礎的電腦適性測驗評量系統，可以快速且正確將學生作 答情形分析，達成受試者能力值的估計。 二、 透過以a-鄰近法為選題策略之電腦適性測驗評量模式，可以有效達成曝光率 控制的目的。 三、 以a-鄰近法為選題策略之電腦適性測驗評量模式，可以有效節省時間和試 題。

Abstract Computerized adaptive test can be used to test the students in accordance with their capabilities, which not only shorten the testing time but also accurately evaluate the performance of the students. The successful elements of CAT are defined by the accuracy of traits estimation and the control of testing items exposure rate. To date, the study in the controlling item exposure rate is conducted by the computerized simulation system, which was not an actual system available for testers. The purpose of the study is to develop an online Computerized Adaptive Testing System for testing the primary school – the third grade on their mathematics competence. The system is building upon the testing item bank of “Mathematics Competence Indicators for primary school third grade”, Shu-Ching Wang (2005) , and incorporating the techniques of testing theory, the controlling of testing item exposure rate and the Internet network. Regarding the research methods, the Computerized Adaptive Testing System, which is incorporated with the Item Response Theory and a-Nearest-Neighbor Strategy, proceeds with controlling the testing item exposure rate and can accurately estimate testers competences. Furthermore, the records of response procedures of all students are collected as the data for controlling exposure rate. The research results are as follows: 1. The Computerized Adaptive Testing System, building upon Testing Item response theory, can be used to analyze students problem solving and responding capabilities in an instant and accurate manner. 2. The Computerized Adaptive Testing System, building upon a-Nearest-Neighbor Strategy for testing item selection, can be used as an efficient approach to control item exposure rate. 3. The Computerized Adaptive Testing System, building upon a-Nearest-Neighbor Strategy for testing item selection, can effectively shorten the testing time and decrease the quantity of testing items.