摘 要:資產市場間的收益和波動相關性方面,許多已有工作并沒有形成一致結論。本文從周度時間跨度視角,構建了VAR-DCC-MVGARCH模型,采用了2005年7月至2011年3月的交易數據,在一個框架下考察了我國石油、黃金、利率、匯率和股票市場的動態相關性。結果表明,利率對匯率、石油對匯率、黃金對利率、黃金對石油存在著單向均值溢出效應,僅在股票與黃金市場間具有雙向均值溢出效應;各市場波動性之間均具有動態時變特征,其中,股票與利率、匯率與利率、石油與匯率、黃金與匯率具有負相關性,股票與石油、股票與黃金、黃金與利率、黃金與石油間呈現出正向關聯。最后,將結果與現有文獻進行了比較和探討。
關鍵詞:均值溢出效應;動態條件相關性;多元GARCH模型
中圖分類號:F830 文獻標識碼:A 文章編號:1003-5192(2012)02-0007-06
Dynamic Correlation Studies on Physical Assets and Financial Asset Market in China
——An Empirical Test Based on VAR-DCC-MVGARCH Model
LI Hong-xia, FU Qiang
(College of Economy and Business Administration, Chongqing University, Chongqing 400030, China)
Abstract:The relationships among asset makets have long been unresolved issues in the finance literature. By constructing the VAR-DCC-MVGARCH model and adopting the weekly data between July 2005 and March 2011, this paper studies mean spillover effects and dynamic conditional correlations among oil, gold, interest rate, exchange rate and stock markets in China. Our findings are as follows. There are uni-directional relations of mean spillover effect from interest rate to exchange rate, oil to exchange rate,gold to interest rate and gold to oil, while the mean spillover effect between gold and stock markets is bi-directional.Additionally, the correlations of volatility are time-varying in all the cases,and there exist significiantly negative relationships between stock and interest rate, exchange rate and interest rate, oil and exchange rate, and gold and exchange rate.Meantime, the positive correlations are founded between stock and oil, stock and gold, interest rate and gold, and oil and gold. Finally, we compare the results with the existing literature.
Key words:mean spillover; dynamic conditional correlation; MVGARCH model
1 引言
資產市場間收益和波動的關聯性分析是資產定價及投資組合理論的重要基礎。20世紀90年代以后,隨著Granger因果檢驗、協整方法和GARCH模型簇等計量手段的廣泛應用,資產間溢出效應和相關性檢驗成為了持續研究熱點。總體而言,國內外現有文獻大多關注了兩種資產市場間的相互關聯,大體可歸納為三類研究重點:
其一,股票市場、利率和匯率之間的相關性。這可劃分為三個研究主題:(1)股票與匯率。在國外金融文獻中,匯率和股票之間的關系一直是懸而未決的話題。Smith[1]和Dominguez Tesar[2]等發現匯率對于股價存在正向影響,Solnik[3]和Kim[4]揭示出股價和匯率間存在一個強烈的負相關,而Nieh Lee[5]卻認為匯率改變和組合股票收益率之間并不存在顯著的相關性。……