This factor captures the changes in the co-occurrence relationship between stocks and industries in news reports, namely industry co-occurrence momentum. When a stock appears in the news with more industries, it may reflect the market's attention to the company's cross-industry influence or the diversification trend of the company's business. In the A-share market, this factor shows a negative correlation with future returns, which may be due to the market's excessive attention or hype about this cross-industry connection, resulting in excessive overvaluation of stock prices in the short term, followed by mean reversion. Therefore, this factor can be used as a reverse indicator to assist in judging the potential callback risk of stocks.