In this paper, we introduce the first dataset that records the news co-mention relationships in the Chinese A-share market. In total, we collected 1,138,247 pieces of news articles that at least mentioned one listed firm in the A market from major Chinese media and financial websites from September 1999 to December 2022. The development of this dataset could enable data scientists and financial economists to investigate the network of stocks through news co-mention in the Chinese stock market. The dataset could also help to construct novel portfolio strategies like the cross-firm momentum strategy with news-implied links as in Ge et al. (2023).

Exploiting ffnancial news stories data, we construct news-implied linkages and document a strong lead-lag effect of ffrms with shared news coverage in China’s stockmarket. The news-link momentum strategy generates a monthly return of 1.33% and a four-factor alpha (Liu et al., 2019) of 1.43%. While prior evidence on the attention dynamics among ffrms with joint news coverage is limited, we show that the momentum spillover of news-linked ffrms is largely driven by investor underreaction. The return predictability from news links is also robust to controlling for alternative economic linkages. The ffndings suggest that information diffuses sluggishly among news-connected ffrms, thereby providing new evidence on the implication of media coverage for pricing efffciency.

Existing research does not find significant momentum profits in many emerging markets including China. We propose an alternative momentum strategy which groups stocks into return intervals rather than percentiles. We apply the method to the China A-share market and find economically significant momentum profits in weekly returns, but not in monthly returns. The weekly momentum lasts for about 1 year. More than half of the profit is realized in the first 3 weeks. We apply the method to other Asian equity markets and find significant weekly momentum in Hong Kong, Taiwan, Korea, Thailand, and Indonesia. These findings suggest that momentum may exist in different formats in different markets. Existence of momentum in a closed equity market like China supports momentum is pervasive in short-term stock returns.

This paper mainly finds that there is return predictability across equity-link firms in China’s stock market. By grouping the shareholder firms according to the shocks translated from their equity-link firms, we construct long-short momentum strategy to capture abnormal return of 2.01% per month, which we call “equity-link momentum”. After an array of adjustments based on risky factors and firm characteristics, the excess returns are still significant. However, the significance of equity-link momentum returns are sensitive to various attention proxies, such as firm size, past performance, turn over and mutual funds’ joint holding measurement, which is consistent with the hypothesis of limited attention.

In this paper, we pay attention to the relationship between stock index and increments of trading accounts in A, B share market and funds. We show that there exists bilateral relationship between A, B index and their trading accounts increments. However, Granger causality only exists from stock index to increments of funds accounts. Regressions show that the investors’ sentiment will be easily driven by the index in the same direction, which imply momentum strategy in a very short period. In comparison, when using weekly data, only increments of funds accounts Granger cause the stock index. These uncover the differences between fund managers and small investors while investing on stock market. We also analyse the relationship between index volatility and trading accounts volatility.

While the vast majority of the literature reports momentum profitability to be overwhelming in the U.S. market and widespread in other countries, this paper finds that the pure momentum strategy in general does not yield excess profitability in the Chinese stock markets. We find instead strong mean reversion with an average half-life slightly shorter than one year. A pure contrarian investment strategy produces positive excess returns and in general outperforms the pure momentum strategy. Furthermore, momentum may interact with mean reversion. A strategy based on the rolling-regression parameter estimates of the model combining mean reversion and momentum generates both statistically and economically significant excess returns. The combined strategy outperforms both pure momentum and pure contrarian strategies. We conduct a number of robustness tests and confirm the basic findings. Collectively, our results seem to support the overreaction hypothesis.