Advanced GARCH Modeling Techniques and Risk-Return Relationship in the Vietnamese Stock Market

2026-03-05T10:38:43+00:00

This study investigates the Vietnamese stock market volatility focusing on the VN-INDEX from the Ho Chi Minh Stock Exchange, during the period 2004-2024. Both symmetric and asymmetric GARCH models are implemented with three different error term distribution assumptions to analyse the volatility persistence and clustering as well as any leverage effects on stock returns. The best fitting model for the dataset seems to be the EGARCH (2,1) using a Skew-t distribution assumption. The positive risk-return link is confirmed, with higher volatility associated with greater expected returns. This is one of the very few studies focused on a long period that moreover includes the effects that some unexpected exogenous shocks (like the Covid-19 pandemic and other recent geopolitical events) could generate on the parameters estimates. Thus, it can encompass different market phases, including years of economic growth, stability, volatility, and downturns, thus offering a comprehensive view of the Vietnamese market’s behaviour under dissimilar economic and financial conditions. This research offers valuable insights into the nature of uncertainty in the Vietnamese stock market, helping investors in their decision-making processes and contributing to the overall understanding of the market. Indeed, understanding volatility and its implications is essential for investors, policymakers, and researchers, particularly in emerging markets like Vietnam, where financial systems are evolving rapidly.

Environmental Clean-Up Costs and the Financial Performance of Plastic Companies in Douala

2026-06-16T14:16:00+00:00

In light of the on-going debates about the widely debated trade-off between environmental responsibility and financial performance of companies, this study was conducted to investigate the relationship between environmental clean-up costs and the financial performance of plastic manufacturing companies in Douala. An ex-post facto research design was employed and the analysis based on 40 firm-year observations from 2016 to 2023. The data analysis was conducted using the Ordinary Least Square technique applied to the pooled panel data. The empirical evidence disclosed that the direct financial burden of environmental clean-up costs does not significantly impair the overall profitability of the company. Secondly, the key drivers of financial success in the plastic manufacturing companies appear to be the firm size and the operational efficiencies associated with it rather than environmental clean-up costs. Thirdly, most successful firms are the larger ones that have likely integrated more efficient processes, leading simultaneously to better financial outcomes and a reduced need for reactive environmental clean-up cost spending. Based on these findings the policy recommendations are that: plastic manufacturing concerns should prioritize investments in operational efficiency, modern production technologies, and waste minimization processes; the government should institute a policy approach that supports and enables firms to modernize by creating incentive structures such as tax credits or grants that encourage firms of all sizes to invest in cleaner production technologies.

Asian Journal of Finance & Accounting

Advanced GARCH Modeling Techniques and Risk-Return Relationship in the Vietnamese Stock Market

Environmental Clean-Up Costs and the Financial Performance of Plastic Companies in Douala