选择题作为客观性试题的主体,越来越受到教师的欢迎。它不但具备答案唯一、评分客观的优点,而且由于布设了“迷惑性答案”,就更容易暴露考生的知识缺陷,从而可直接地考查学生在知识上的不定性程度。同时,这种考题便于积累、修改、拆拼。深入研究并逐步推广选择题,对推行标准化考试和推动教育科研定量化有其重要意义。本文拟从信息量的角度对选择题作一点分析。一、关于“信息”的概念考试的实质是命题人以考卷的形式向答卷入寻求信息的过程。命题人可视为一个收集信息的人,信息论中称“信宿”;而答卷人则充当信息的提供者,信息论中称“信源”。“信宿”在获得信息之前,在知识上提出一个“不定性”的初量值,比如,命题 As the subject of objectivity test questions, multiple choice questions are increasingly welcomed by teachers. It not only has the advantage of unique answers and an objective rating, but it also makes it easier to expose candidates’ knowledge deficiencies by laying out “disturbing answers”, so that students’ level of ambiguity in knowledge can be directly examined. At the same time, such examination questions are easy to accumulate, modify, and disassemble. In-depth study and gradual promotion of multiple-choice questions are of great significance to the implementation of standardized examinations and the promotion of quantification of educational research. This article intends to analyze the multiple choice questions from the perspective of information volume. I. The essence of the concept test of “information” is the process in which the propositioner asks for information in the form of an examination paper. The proposition person can be regarded as a person who collects information. In information theory, he is called “Sinxa”; and the respondent serves as a provider of information. In information theory, he is called “a source of information.” Before the information is obtained, “Sinxuan” proposes an initial value of “uncertainty” in knowledge, for example, propositions.