ARMA analysis of the green innovation technology of core enterprises under the ecosystem – Time series data

From the perspective of innovation ecology, the green innovation of core enterprises is a key to high-quality economic development. This paper researches BYD, makes a discussion on the evolution and characteristics of green innovation, and clarifies the driving force of green innovation of core enterprises in the green innovation ecosystem. In addition, the 2002–2019 green patent authorisation data of BYD is selected as the green output indicator of the core enterprise. And through testing the data, the findings are that the perturbation term ε is white noise, which meets the zero expectation E(ε_t) = 0, and the same variance Var(ε_t) = σ² and that there is no autocorrelation Cov(ε_t, ε_s) = 0, t ≠ s. The ARMA model is hence constructed for analysis. Through analysis, conclusions are drawn that when the core enterprises and other entities in the green innovation ecosystem collaborate to innovate, the complexity and dynamics could be found in the green innovation evolution process and that as an important driving force for green innovation, innovation input not only raises current green output but also facilitates future green output.