Innovation ambidexterity, namely, performing exploitative and exploratory innovation simultaneously, is important for high-tech firms to achieve sustainable success. This can be achieved by building an egocentric alliance network. Research into the influence of alliance network diversity on innovation ambidexterity is seeing more attention. However, the differences among multiple alliance network diversities are unclear. Grounded on a knowledge-based view, organizational learning theory, and transaction cost theory, this study investigates in-depth the roles of geographical diversity, industrial diversity, and functional diversity of the alliance network. The empirical analysis based on panel data, including alliance data from the SDC Joint & Venture database and patent data from the Derwent Innovation Index database of 106 top high-tech firms from electronic information and biopharmaceutical industries, suggests that industrial diversity enhances firm innovation ambidexterity, geographical diversity impedes firm innovation ambidexterity, and functional diversity shows an inverted U-shaped relationship with firm innovation ambidexterity. These results provide practical suggestions about alliance network diversity configuration and innovation ambidexterity construction for high-tech firms. Sustainability 2020, 12, 1041 2 of 16 composition [17,18], network capability [19,20], network embeddedness [21], network position [22], network brokerage, network tie strength [23], and network dynamics [24], were also found to impact ambidexterity.Recently, increasing attention is being paid to alliance network diversity. Researchers have considered various dimensions of alliance network diversity from the perspectives of partner attributes and alliance attributes [25], including partner type diversity, technological diversity, industrial diversity, geographical diversity, and functional diversity [26,27]. Partner type diversity indicates the diversification of partners including business partners, customers, suppliers, competitors, and venture capital firms, and knowledge partners including universities, research institutions, technology intermediaries, intellectual property organizations, and government agencies. The fact that knowledge partners mainly engage in R&D activities, while business partners primarily engage in production, marketing, or financing suggests that partner type diversity could be reflected by functional diversity. Furthermore, technological diversity mainly indicates the diversification of technology affiliated with alliance partners, which can be reflected by the industrial and national background of partners in the global industry division of innovation. In this respect, it may overlap with industrial diversity and geographical diversity. As such, the industrial diversity, geographical diversity, and functional diversity, which indicate the diversification of industrial background, national background of network partners, and functional attributes of alliance activities, respectively, are investigated...
