School of Economics and Business Administration, Chongqing University, Chongqing, China.
School of Economics and Management, Chongqing Normal University, Chongqing, China.
PLoS One. 2020 Jul 31;15(7):e0236626. doi: 10.1371/journal.pone.0236626. eCollection 2020.
Different consumer groups accept new energy vehicles sequentially from the perspective of innovation diffusion theory, and the early adopter group has recently been identified. By assuming that the density of early adopters is increasing at minimum acceptable quality thresholds, this paper proposes a vertical quality differentiation model of product R&D with product subsidies. The impact of product subsidies on the R&D investment of new energy vehicle firms is discussed. We show that the early adopters' characteristics may affect the stagnant marginal R&D investment of new energy vehicle firms by increasing sales, which determines the impact mechanism of product subsidies. For firms with decreasing marginal R&D investments, insufficient R&D investments result from financial constraints. If insufficient R&D resources deter firms from conducting R&D, substantial unit subsidies invariably incentivize firms to spend their entire R&D budget. Firms with increasing marginal R&D investments, insufficient R&D profits, or financial constraints are prevented from increasing R&D investment. Product subsidies generally have a crowding-in effect on firms not subject to financial constraints, and this effect increases with the unit subsidy. However, the existence of a crowding-in effect may require sufficiently large unit subsidies. In both situations, product subsidies cannot modulate financial constraints if the firm has spent its entire R&D budget. In the first situation, we also show that product subsidies should be replaced by a funding support policy. In contrast, the second situation shows that a funding support policy should be coordinated with product subsidies.
从创新扩散理论的角度来看，不同的消费群体依次接受新能源汽车，最近已经确定了早期采用者群体。本文假设早期采用者的密度在最低可接受质量阈值处增加，提出了一种具有产品补贴的产品研发垂直质量差异化模型。讨论了产品补贴对新能源汽车企业研发投资的影响。我们表明，早期采用者的特征可能通过增加销售量来影响新能源汽车企业停滞的边际研发投资，这决定了产品补贴的影响机制。对于边际研发投资递减的企业来说，研发投入不足是由于财务约束造成的。如果研发资源不足阻止企业进行研发，那么大量的单位补贴必然会激励企业花费其全部研发预算。边际研发投资递增、研发利润不足或财务约束的企业则无法增加研发投资。产品补贴通常对不受财务约束的企业具有挤入效应，而且这种效应随着单位补贴的增加而增加。然而，这种挤入效应的存在可能需要足够大的单位补贴。在这两种情况下，如果企业已经花费了全部研发预算，产品补贴都不能调节财务约束。在第一种情况下，我们还表明，产品补贴应该被资金支持政策所取代。相比之下，第二种情况表明，资金支持政策应该与产品补贴相协调。
