Through examining the characteristics of the judges' scoring and the group decision-making mechanism, it is found that in the incomplete scoring system, especially in the subjective scoring competition, there exists a large error in the ranking results of the traditional method or the T score method. In order to improve the scientificity of ranking, a mathematical model is established to distribute the papers evenly among the judges, and then the weight of each judge is determined by the minimum sum of the squares of ranges. Finally, the ranking is determined according to the weighted average value of each paper's scores. Simulation results show that, compared with the traditional and standard score methods, the new method can improve the coincidence of subjective and objective ranking and reduces the disorder degree. By calculating the Euclidean distance, it is proved that the new method can reduce the experts' scoring error and the resulting controversy.