“…Statistical tests for these common jump events, known as "cojump tests", implicitly assume that jumps happen at the same time across all relevant assets but, in fact, jumps occur asynchronously in transaction data. Empirical studies support this view: stock prices can move sluggishly (Bandi et al, 2017), jumps may develop gradually (Barndorff-Nielsen et al, 2009), jumps of less-liquid individual assets typically lag those of the more-liquid market index , and at an ultra-high frequency, cojumps are spurious (Bajgrowicz et al, 2016). Most researchers have dealt with this problem by settling for a coarse sampling grid (Barndorff-Nielsen et al, 2009;Bollerslev et al, 2008;Lahaye et al, 2011;Li et al, 2019).…”