20 19 Number Two Difficulty in Postgraduate Entrance Examination
20 19 introduction to the entrance examination of mathematics 2: the sample size of mathematics 2 is 137200, and the difficulty coefficient is 0.40 1. The actual situation may be less than 0.4, so it is most reasonable to increase the sample size, and the difficulty coefficient is 0.5-0.55. If it is less than 0.5, it is more difficult, and 0.4 is too difficult. In the past 20 years,