中文摘要：

研究了规模不经济对制造商直销渠道选择的影响。运用博弈论建立了单渠道和双渠道供应链决策模型，得到了Bertrand均衡的渠道价格以及制造商和零售商最优利润。研究发现当零售商潜在市场份额较小时，若制造商规模不经济不明显，制造商开通直销渠道；若制造商规模不经济明显，制造商不开通直销渠道。当零售商潜在市场份额较大时，制造商不开通直销渠道。此外，直销渠道总是侵蚀零售商利润。

英文摘要：

This paper studies the effects of manufacturer＇s scale diseconomies on the choice of the manufacturer launching online direct channel. In the symmetric-information framework, the manufacturer＇ S scale diseconomies Bertrand models are proposed between single-channel and dual-channel supply chains. The optimal prices and profits are compared between single-channel and dual-channel supply chains of Stackelberg competition. This paper demonstrates three interesting results： （i） when the retailer has less market shares and the manufacturer＇ s production exhibits its low diseconomies of scale, the manufacturersr decides to launch online direct channel in order to increase profits. （ ii ） if the retailer has less market shares but the manufacturer＇ s production exhibits its high diseconomies of scale, the manufacturer declines to launch online direct channel. （ iii） only if the retailer has more market shares, the manufacturer declines to launch online direct channel. In addition, the retailer＇ s profit always decreases while the manufacturer launches online direct channel