Theoretical Investigation on R&D Investment and Oligopolistic Models with Spillovers

1.有出口企业的政府是否采用出口补贴作为贸易政策取决于R&D溢出水平和R&D投资的相对成本。例如，当相对成本较高或不太高，溢出水平较大时，最优贸易政策是自由放任还是出口税，即可能性取决于两个水平。出口补贴对出口的促进作用和R&D投资的促进作用均增强。R&D投资溢出存在的战略模型以及非战略模型。此外，尽管古诺数量竞争下的企业是否战略性地使用RED投资取决于溢出水平，但Bertrand价格竞争下的企业使用R&D的动机很小。企业是否披露其研发成果取决于需求函数中交叉价格效应的符号，而与企业在市场上是参与数量竞争还是价格竞争无关。此外，寡头企业组成的研发卡特尔将增加研发支出和利润。当产品具有替代性时，数量竞争下的企业在有R&D合作的情况下比没有R&D合作的情况下获得更多的收益。

1. Whether or not the government with export firms employs export subsidies as trade policy depends on both levels of R&D spillover and the relative cost of R&D investment. For example, when either the relative cost is high or it is not so high and the spillover level is relatively large, the otimal trade policy is laisser-faaire or export tax : namely, the possibility depends on both levels. Export subsidies cause the promotion of export and R&D investment to increase.the strategic model with R&D investment in the presence of its spillover as well as for the nonstrategic model. Moreover, although whether or not firms under Cournot-quantity competition use RED investment strategically depends on the level of spillover, the incentive for firms under Bertrand-price competition to use R&D is small.3. Whether firms disclose their results created by R&D depends on the sign of the cross price effect in terms of a demand function, irrespective of whether the firms are involved in quantity or price competition in the market. Moreover, the formation of an R&D cartel of oligopolistic firms will increase both R&D expenditure and profits. When products are substitutes, firms under quantity competition will obtain more in the presence of R&D cooperation than in the absence of it.