In many applications, the objective function is determined by several parameters simultaneously. Properly assessing the relative contribution of each parameter can give the decision maker a better understanding of the problem. However, widely used assessing methods are qualitative or semi-quantitative. In this paper, a new concept, relative contribution ratio (RCR), is proposed. The concept follows the idea of proof by contradiction, and estimates the impact of absence of each parameter, based on the fact that the absence of a parameter with more contribution will bring more divergence. Based on surrogate models, a statistical method for calculating RCR is also presented. Numerical results indicate that RCR is capable of analyzing multi-parameter problems, regardless of whether they are linear or nonlinear.