This paper investigates the effectiveness of a market surveillance system (MSS) on improving the market quality of the Vietnamese stock market, as measured by liquidity and informed trading level. We find that market liquidity decreases after the introduction of the MSS, and that the effect is more pronounced for small firms. Although the level of informed trading, on average, does not change significantly after the MSS, the subsample analysis indicates a significant decrease in informed trading among large and liquid firms.

中文翻译：

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流动性，知情交易和市场监控系统：越南股票市场的证据

本文研究了以流动性和知情交易水平衡量的市场监督系统（MSS）在改善越南股市质量方面的有效性。我们发现，引入MSS后市场流动性下降，并且这种影响对于小企业更为明显。尽管平均而言，在MSS之后，知情交易的水平没有显着变化，但子样本分析表明，大型和流动性公司之间的知情交易显着减少。