Integration between East and Southeast Asian equity markets
Authors: Arsyad Nuruzzaman 
Published: April 2015

Purpose
– This paper aims to seek to find answers to three questions. First, is there any possibility of long-term cointegration between East and Southeast Asian equity markets? If so, how many cointegrating equations are there? Second, what are the short-term causal relationships between equity markets in East and Southeast Asia? Third, what is the East Asia’s most influential equity market toward their Southeast counterparts, and vice versa?

Design/methodology/approach
– This study uses Johansen's (1988) cointegration method to test long-run relationships among East and Southeast Asian equity markets. With regards to short-run causal relationships, this study uses Granger-causality test as well as the forecast variance decomposition method.

Findings
– Johansen test proves that there is cointegration between East and Southeast Asian equity markets, but the integration process is not complete. Cointegrating vector also provides evidence that member countries of ASEAN+3 respond differently to external shocks. With regards to short-run causal direction, this study finds that Japan Granger-causes all equity markets in Southeast Asia, while Singapore and Vietnam Granger-cause all equity markets in East Asia. These results imply that Japan is the market with most linkages in Southeast Asia, while Singapore and Vietnam are the markets with most linkages to East Asia. Furthermore, forecast variance decomposition reveals that Japan is the East Asia’s most influential equity markets, while Singapore is the most influential equity market in Southeast Asia. This study suggests that policymakers in East and Southeast Asian countries to synchronize the capital market standards and regulations as well as to reduce the barriers for capital mobility to spur the regional equity market integration.

Research limitations/implications
– Increasing integration of East and Southeast Asian capital markets forces policymakers in ASEAN+3 countries to synchronize monetary policies, as it has been found that regionally integrated capital markets reduce the degree of independent monetary policy (Logue et al., 1976). It is therefore important for policymakers in East and Southeast Asian countries to assess the possibility of stock market integration within this region to anticipate the future risks associated with economic integration as well as to build collective regional institutions (Wang, 2004). Click and Plummer (2005) also argued that integrated stock markets is more efficient than nationally segmented equity markets, and the efficiency of Asian capital markets has been questioned in particular after the 1997 Asian financial crises. Yet, the empirical evidence on the extent of financial integration among ASEAN+3 member countries has been limited and inconclusive. This study is therefore an attempt to investigate the recent development of ASEAN+3 equity markets integration.

Practical implications
– This study focuses its attention on the existence and the extent of financial integration in East and Southeast Asia region, and it provides evidence that equity market integration in ASEAN+3 is far from complete, and for that reason, there is a need for policymakers in ASEAN+3 member countries to synchronize their standards and regulations. Furthermore, the policymakers in East and Southeast Asia can gain benefit from this study, as it provides the evidence that ASEAN+3 member countries respond differently to policy shocks, which may hinder the development of regional financial integration as well as the policy effectiveness of region-wide authority in ASEAN+3.

Originality/value
– This research is different from previous studies, as it puts the regional financial integration within the context of ASEAN+3 frameworks. Unlike previous research that considers East and Southeast Asian countries as an individual entity, this research considers East and Southeast Asia into two different blocks, following Tourk (2004) who documented that negotiation process for ASEAN+3 financial integration is conducted in sub-regional level (ASEAN vs East Asia), rather than national level (country per country basis). Second, this study covers the period after the 1997 Asian financial crisis. As suggested in Wang (2014), that the degree of stock market integration tends to change around the periods marked by financial crises, the updated study on Asian financial integration in the aftermath of 1997 financial crises is important to document the development of regional financial integration.