A combined multi objective model to supplier evaluation and selection and order allocation using AHP and TOPSIS

Supplier selection and allocating orders to them accurately, is one of the most important challenges in supply chain management.The reasone is that an incorrect choosing suppliers can disrupt the financial and technical position of supply chain. Whereas the supplier selection is a multi-objective decision making with multiple criteria problem, in this paper a linear multi-objective mathematical programming model is presented. In this model, Analytic Hierarchy Process (AHP) has been used for determining supplier’s priority (weight). By choosing proper evaluation criteria, appropriate number of suppliers and suitable amount of row material orders from each supplier can be specified. The presented model is a mathematical programming model that includes five objective functions and several contraints. Epsilon constraint method is applied to solve the model using a pharmaceutical company data. Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) has carried out to determine the best answer Among Pareto solutions. The results of numerical example and sensitivity analysis show the applicability of the suggested model.