关键词: 客户集中度, 创新投入, 创新产出, 交易成本, 联结强度

Abstract: Relationship-based transactions of listed companies in China are rooted in the formal systems such as legal, political and administrative management systems, as well as the formal systems such as customs and etiquette, and the concentrated customer/supplier relationship is one of its main manifestations. The relationship-based transactions between enterprises and major customers have a great influence on both sides. Domestic and foreign researches on relationship-based transactions mainly focus on the impacts of customer concentration on accounting conservatism, earnings management, profitability, loan contracts, and working capital management. On the one hand, in order to maintain long-term stability of relationship-based transactions, firms may improve accounting conservatism, or conduct earnings management. To deliver firms′ good financial status to major customers and guarantee the long-term cooperation, firms have motivations to enhance accounting conservatism; And to influence customers′ views on the prospect of firms′ future development, they may carry on earnings management. On the other hand, relationship-based transactions, not only mean stable product demand and income, but also may mean excessive dependence on major customers and easily affected by whether the financial situation of major customers is stable, which has an important influence on firms′ profitability, loan contracts and working capital management and so on. Customers concentration can improve firms′ profitability; The higher the customer concentration, the stronger the firms′ ability to obtain bank loans; Suppliers may increase their cash holdings for precautionary motivation in order to avoid customer churn.
In order to maintain relationship-based transactions with major customers, except for improving accounting conservatism and conducting earning management, firms may also make relationship-specific investments. Innovation input as an important aspect of relationship-specific investments, will be affected by relationship-based transactions? And how do relationship-based transactions affect firms′ innovation output? In terms of relationship-based transactions and corporate innovation, scholars have explored the impact of supply chain relationship on corporate innovation output in the form of theoretical analysis and case analysis. Bellamy et al. (2014) find that, supply network accessibility and supply network interconnectedness can improve greater innovation output, and the interaction between supply network accessibility and supply network interconnectedness, the moderating role of absorptive capacity on supply network accessibility, and the moderating role of supply network partner innovativeness on supply network interconnectedness also can facilitate innovation output. It can be seen that, the characteristics of the relationship between the two parties during the process of the transaction have a significant impact on corporate innovation. But the research on the impact of customer concentration on corporate innovation has not been discussed in-depth. Based on transaction cost theory and strong or weak ties theory, the paper explores the function ways and mechanism of customer concentration on corporate innovation input and output, which help deepen the understanding of how relationship-based transactions affect firms′ behaviors and decisions. And the paper focusing on the relationship between customer concentration and corporate innovation has theoretical exploration value and practical reference significance.
Using a sample of Chinese A-Shared listed companies from 2009 to 2015, the article explores the influence of customer concentration on corporate innovation input and output. The empirical research results show that customer concentration and innovation input is the U-Shaped relationship. That is, before the degree customer concentration reaches a certain point, firms′ innovation input decreases with the improvement of customer concentration due to the possibility of customer opportunistic behaviors. After the customer concentration increasing to a certain degree, the two parties gradually establish trust during the process of transaction, and the firms′ innovation input increase with the improvement of customer concentration. What′s more, customer concentration and innovation output is also a U-Shaped relationship, which confirms the impact of the strength of weak ties on corporate innovation. Namely, when the customer concentration is low, the weak ties between firms and customers help gain new knowledge and information, and then it makes the corporate innovation output achieve a higher level. But with the gradual improvement of customer concentration, the impacts of weak ties weaken, then the corporate innovation output drops. After the customer concentration reaches to a certain degree, the strong ties between firms and customers help share knowledge and technology, and then it promotes the continuous rise of innovation output. In addition, the results show that, innovation input plays a partial mediating role in the relationship between customer concentration and innovation output. Lastly, the U-Shaped relationship between customer concentration and corporate innovation is more significant in the group in which firms′ products are unique and which belongs to high technology industries.
This study makes several contributions to the current literature. Firstly, starting from the firms′ external stakeholders, the paper selects a unique perspective of the customer relationship in the supply chain, analyzed and confirmed the impact channel and mechanism of the relationship-based transaction on corporate innovation input and output. It enriches the extant studies about customer concentration and relationship-based transactions. Secondly, based on the transaction cost theory and strong or weak ties theory, the study constructs a new analytical framework, which provides a new theoretical explanation for the influence of customer concentration on corporate innovation. Thirdly, the article proposes and verifies the U-Shaped relationship between customer concentration and corporate innovation, which provides empirical evidence on this important research topic. Finally, the paper makes an in-depth analysis of the different influences of the nature and degree of customer relationship on corporate innovation, which has certain practical significance for supply chain relationship construction, customer relationship management, and corporate innovation decision.

Key words: customer concentration, innovation input, innovation output, transaction cost, strength of tie