A Study On Optimal Starting Time With Demand Substitution Between Products

With new technology and new production methods coming, market competitiveness is becoming fiercer,so products life cycle are becoming much shorter. Demand shifts between products are more usual. So how to decide starting time for new products to harvest the profit of the old product and to maintain the competitiveness of the company is an important task.This thesis has analyzed what is demand and how to express the demand shift based on demand shift between new product and the old one; discovers that these definitions put on by researchers although are helpful to further know about the demand substitution phenomenon, but it does not tell us how to Weigh the enterprise's demand shift; Many researchers do not have considered the income shift to the enterprise's other products. Therefore it is not inclusive. The author in this paper has considered the total income with the new and old products. At last, this thesis has established quantitative models, finding out the factors influencing the starting time of the new product including the left selling time for the old product and its declining speed. Compared with predecessor's researches, This thesis has made further researches, but because the factors influencing demand shift were a lot, Simultaneously in the mathematical model establishment process, this thesis has made very many suppositions, these suppositions with the enterprise's actual situation also has the certain disparity, so this paper's conclusion needs further to prove in the next research.