The Applied Research And Construction Of A Model For Exam Difficulty Assessing Of NCHO

The examination for National Chemistry Olympic (NCHO) tends towards high selectivity which is determined by the purpose of this competition. Besides the efforts made in psychometrics, scholars have done fruitful researches on measures and techniques of exam difficulty assessment. Especially factors influencing the difficulty level of National Matriculation Entrance Test (NMET) have recently been discussed in detail. And new ways to predict the difficulty level of a coming examination have also been explored and tried. Based on the previous studies, this thesis takes NCHO as its subject, which is broadly-known in the chemistry education field, and tries to construct a model for exam difficulty assessing. And related studies are also done in this thesis.During the research, methods such as questionnaires, mathematical statistics, sampling tests and contrast analysis are employed. The research is carried out in the following way:First, after a thorough literature review of the previous studies, the hypothesis about the factors influencing the difficulty level of NCHO is proposed. A model for quantitative measurement of difficulty level is constructed after statistical analysis on the data collected from the questionnaires done by teachers coaching in NCHO.Second, using this model, the degree of difficulty in knowledge and competence required in the exams from the year 2006 to 2009 can be quantified, thereby showing the difficulty level's tendency of the coming exam.Finally, let some contestants answer some questions selected from the past exams'papers of NCHO. According to the information reflected on their answer sheets, the disturbance of thinking encountered by them in the process of problem solving are discussed through comparative analysis between the predicted difficulty level and the actual difficulty level.All in all, based on the above investigation and study, it is found that students, when solving the problems, are better at deductive reasoning rather than inductive reasoning. Attention should be paid to the accumulation of useful knowledge when teaching element chemistry. While both accumulation of knowledge and the reasoning ability should be emphasized when teaching theoretical knowledge.