1、Chapter Three Some Essential elements in maintaining or evaluating test quality （语言测试的基本要素 ）,What do we need to know ?,Teaching objectives of this chapter ： what is test reliability ？How can we check the test reliability? what is test validity？How many kinds of validities ？ what is the relationship
2、between test reliability and validity ？ the other elements in language testing .,I. What is test reliability? 语言测试的信度，指的是测试结果是否可靠可信。（李筱菊，1997）,According to Henning( 2001), reliability is a measure of accuracy, consistency, dependability, or fairness of scores resulting from administration of a parti
3、cular examination. For the individual , however, the reliability is said to be associated with the tendency of his or her score not to vary with repeated measurement.,II.How can you measure the testing reliability in practice?,Three ways: 1.test-retest testing method(重复测试法）. ( consistency over time)
4、 2.parallel-form testing method(平行卷测试法）(consistency in form) 3. split-half testing method.（对半分析法）( internal consistency ),III、What is test validity?,语言测试的效度也称有效性,指测试所考的,是否就是所要考的,或者说,在多大程度上是考了目的所要考（李筱菊,1997）。 Validity in general refers to the appropriateness of a given test or any of its component pa
5、rts as a measure of what it is supposed to measure. A test is said to be valid to the extent that it measures what it is supposed to measure. Validity may be determined in a variety of ways.,Face validity 表面效度,Clarification of test validity,facrfacr facr,Content validity 内容效度,Criteria-related validi
6、ty 尺度关联效度,Construct validity 结构效度,IV、 Validity in Relation to Reliability Usually, it is possible for a test to be reliable without being valid for a specified purpose, but it is not possible for a test to be valid without first being reliable.,V.some other elements in language testing,Authenticity 真实性,Involvement 交互性,Washback effect 后效作用,Practicality 可操作性,What have you got from the lesson today?,What have you got from the lesson today?,
