2.2.3. Higher-order conditional time-varying momentsThe traditional parametric approach for conditional VaRassumes that the distribution of returns standardised by condi-tional means and conditional standard deviations is iid. However,there is substantial empirical evidence that the distribution offinancial returns standardised by conditional means and volatil-ity is not iid. Earlier studies also suggested that the process of negative extreme returns at different quantiles may differ from oneanother (Engle and Manganelli, 2004; Bali and Theodossiou, 2007).Thus, given the above, some studies developed a new approach tocalculate conditional VaR. This new approach considered that thehigher-order conditional moments are time-varying (see Bali et al.,2008; Polanski and Stoja, 2010; Ergun and Jun, 2010).