This paper focuses on the question of whether or not a reduction of the knowledge barrier is good for welfare. Based on a dynamic monopoly setting with simultaneous investment decisions in process as well as in product Research & Development (R&D), we show that a reduction of the knowledge barrier has ambiguous welfare consequences: due to a lower knowledge barrier, product quality and welfare increase in the short-run. However, this may not necessarily be the case in the long-run. One reason is that a positive long-lasting knowledge barrier shock triggers the monopolist sub-optimally to reduce its product R&D investments today and in the future at the cost of future product quality. This in turn may reduce welfare. Accordingly, to realize the first-best level of product quality, the long-run optimal R&D subsidy rate for product innovations increases with a reduction of the knowledge barrier.

中文翻译：

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动态垄断环境下的知识转移，过渡动力与最优研发政策

本文重点讨论减少知识壁垒是否对福利有利的问题。基于动态垄断环境，同时进行过程决策以及产品研发（R＆D），我们表明减少知识壁垒会产生模棱两可的福利后果：由于较低的知识壁垒，产品质量和福利增加从短期看。但是，从长远来看，不一定是这种情况。原因之一是，积极的，持久的知识壁垒冲击会以最优的方式触发垄断者，从而降低其当前和未来的产品研发投资，而这是以牺牲未来产品质量为代价的。这反过来可能会减少福利。因此，要实现最佳的产品质量水平，长期的最佳R＆R