As a characteristic index of the test paper, the difficulty of the test paper reflects the overall average difficulty level of the topics that make up the test paper. The difficulty value of the test paper can be obtained by the weighted average calculation method of the difficulty of all the questions that make up the test paper. The formula for calculating the difficulty of the topic is Pi=Xi/xi(max). Where Pi= the difficulty of a topic; Xi= the average score of each subject in this question; Xi(max)= full mark of this question; The difficulty of the test paper is the weighted average of the difficulty of the topic. The analysis of examination difficulty is of great significance to teachers. Because of the difficulty of the exam, the class teacher should use relative standards to understand the students' exam results, and the feedback on the students' scores should also proceed from the overall situation. We can't simply judge whether students' academic performance has risen or fallen according to their scores, or whether students have worked hard or slacked off. ?

2. Analyze the reliability and validity of the test paper?

The quality of test papers is often measured by reliability and validity. The reliability of the test refers to the reliability of the evaluation results, that is, the reliability of the test reflecting the students' learning level. Reliability evaluation methods generally adopt retest calculation method and multi-person evaluation calculation method. When analyzing the test results, we can refer to the previous test results and analyze them by calculating the correlation coefficient with the last test results. Generally speaking, the greater the correlation coefficient, the higher the reliability. The validity of the exam refers to the validity of the exam itself. That is, whether the test results reflect what teachers expect. In the analysis of test scores, the analysis of test results can be verified by simple methods. First, take personal evaluation method: feedback the test results to the students themselves, ask them to judge whether the test results are in line with his actual situation, and evaluate the validity by the percentage of the total number of people who agree. The higher the percentage, the better the effectiveness; Second, feedback the test results taken immediately to students, friends or parents who are familiar with the student by using the method of others' evaluation, and ask them to judge whether it conforms to the actual situation of the student, and evaluate the validity by the percentage of the number of people who agree to the total number; The third is the organizational evaluation method, which requires the head teacher and the classroom teacher to judge whether the test results are in line with the actual situation of the students according to the results of the daily teaching process, and to evaluate the validity by the percentage of people who agree.