“…On the basis of the variance decompositions of the VAR model, Diebold and Yilmaz (2009, 2012) provided a new method to study the volatility spillovers between different financial markets, namely spillover index. The advantage of the DY framework is that it can describe the direction of volatility spillovers, and can analyze the dynamics use a simple rolling window method (see Ji et al, 2018; Okorie, 2021; Z. Yang & Zhou, 2017; Yarovaya et al, 2016). Particularly, according to the Fourier transforms of the impulse response functions (IRFs), Baruník and Křehlík (2018) proposed an extension of the DY framework in the frequency domain (see Balli et al, 2019; Liang et al, 2020; Lovcha & Perezlaborda, 2020; Maghyereh et al, 2019; Tiwari et al, 2018; Uddin et al, 2019; X. Wang & Wang, 2019; Y. Wang et al, 2020; Xia et al, 2020).…”