In many R&D-intensive consumer product categories, firms deliver value to consumers through the quality enhancements provided by new and improved versions of existing products. Therefore, important marketing decisions relate to a firm’s strategy for developing quality enhancements and releasing new versions. This paper explores this type of product development using a dynamic duopoly model that endogenizes each firm’s decisions over how much to invest in R&D and when to release new versions. Specifically, I explore how two key industry fundamentals—the degree of horizontal differentiation and the cost of releasing a new version—affect firms’ product development strategies and, accordingly, the evolution of industry structure. I find that varying the degree of horizontal differentiation gives rise to three distinctly different types of competitive dynamics: preemption races when the degree of horizontal differentiation is low; phases of accommodation when it is moderate; and asymmetric R&D wars when it is high. Furthermore, I find that an increase in the cost of releasing a new version can induce firms to compete more aggressively for the lead and, in doing so, release new versions more frequently despite the higher cost.

中文翻译：

---

版本发布的时间：动态双头垄断模型

在许多研发密集型消费产品类别中，公司通过现有产品的新版本和改进版本所提供的质量提升为消费者创造价值。因此，重要的营销决策与公司开发质量增强和发布新版本的策略有关。本文使用动态双头垄断模型探讨了这种类型的产品开发，该模型可内生于每个公司在研发投入多少以及何时发布新版本方面的决策。具体来说，我探讨了两个关键的行业基本原理（水平差异程度和发布新版本的成本）如何影响公司的产品开发策略以及相应地影响行业结构的演变。当水平分化程度低时，抢占竞赛；适度的住宿阶段；以及研发费用高时的不对称研发战争。此外，我发现发行新版本的成本增加会导致公司为争夺领先优势而进行更激烈的竞争，尽管成本较高，但这样做仍会更频繁地发行新版本。