基于双变量EARJI-EGARCH的时变收益关联研究——来自东亚地区股市跳跃的分析

本文改进了双变量EARJI-EGARCH模型,并对东亚地区的中国上证指数,日本日经指数和韩国综合KS指数的跳跃和双边时变收益关联的影响进行了研究。结果表明,东亚地区股市的时变关联持续性非常高,东亚地区单个市场跳跃对时变关联影响较小,市场同时发生跳跃对市场时变关联的影响取决于跳跃的方向。当市场都发生正向的跳跃时,上证和日经指数的时变收益增量最多,当市场都发生负向跳跃时,上证和韩国KS指数的时变收益减少最多。表明在东亚地区股市同向跳跃发生时,中国和日本股市相互关联较大。且同时跳跃对时变关联的影响将远远超过了单个市场跳跃对时变关联的影响,当市场发生反向的跳跃时,也超过了单个市场跳跃的影响,但不及同向跳跃的影响,且上证和日经指数时变收益增加最多,而日经和KS指数时变收益减少的最多,表明在股市反向跳跃时同样是中国和日本股市比日本和韩国股市之间的相互关联大。

The Study of Time-Varying Return Correlations Based on Bivariate EARJI-EGARCH

A bivariate EARJI-EGARCH is improved for study the jumps impact on time-varying return correlations between Shanghai composite index, Japan Nikkei index and Korea KS index. The results show the persistence of correlation in east asian is very high. The outcomes show that individual jumps have small effects on time-varying correlation, the effects of simultaneous jumps depend on the jump signs. The same sign jumps have bigger effects on time-varying correlation than individual jumps,the time-varying return between China and Japan increases most. When the opposite jumps happen, the time-varying return between China and Korea decreases most. It shows that when the same jumps happen, the correlation between Japan and Japan is stronger than the correlation between Japan and Korea.Simultaneous jumps have stronger effects than individual jumps.When reverse jumps happen,they have stronger effect than individual jumps,but weaker than simultaneous jumps.The time-varying return between China and Japan increases most,but Nikkei-KS decreases most.It shows that when reverse jumps happen, the correlation between Japan and China is stronger than the correlation between Japan and Korea.