Collaborative innovation within Platform-based Innovation Ecosystems (PIEs) relies upon the creation of effective partnerships between platform owners and complementors. Despite this, limited research examines the mechanisms that drive collaborative innovation performance within them. To address this important gap, this study performs a fuzzy set Qualitative Comparative Analysis (fsQCA) on 203 Chinese technological firms with the aim of uncovering the distinct configurations of relational elements that drive collaborative innovation within PIEs. The findings reveal three strategies that are equally effective at delivering collaborative innovation: (a) super-modular complementarity in relational operation dependence, (b) unique complementarity in relational operation dependence, and (c) coherence in relational norms dependence. Theoretically, the study contributes to literature on inter-organizational relationships in PIEs and collaborative innovation, by delineating essential relational structures and linking these relational elements to collaborative innovation performance. From a practical standpoint, both platform owners and complementors can use these findings to strengthen their collaborative innovation performance within PIEs.

This paper aims to study on investment return system of public-private partnership (PPP) wastewater treatment projects based on system dynamics. On the basis of the analysis of the factors influencing the value for money (VFM) evaluation and the prediction system of the rate of return on investment, a system dynamics method is used to establish a prediction model for investment income based on VFM quantitative evaluation. The software of Vensim PLE is used to simulate the newly built PPP wastewater treatment project. Results show that the selection of discount rate and PPP project's transaction cost have significant effect on the VFM and the present value and the rate of return on investment in the franchise period. This study can be used as a reference for the fair and equitable cooperation between the government and the private business.

Although the evolutionary pathways are critical to the success of platforms, extant literature has provided little insight into the dynamic processes of the platform evolution, let alone how platforms constitute the evolutionary pathways over time. Against this backdrop, this study examines the evolutionary path constitution of platforms by adopting an organizational momentum lens. Through an exploratory case study of Pinduoduo, it provides evidence of path dependence under the network effects and of path creation resulting from the deliberate actions conducted by the platform firms. Moreover, this study identifies three platform strategies to manage its momentum to facilitate platform evolution and sustainability. Furthermore, this study develops a holistic framework to explain the interactions between platform momentum and path constitution by considering the outcomes of these strategies. The findings and developed framework shed novel light on the path constitution of platform evolution and provide new insight into the sustainability of the platform firms and platform-based markets by leveraging momentum thinking.