Screening A-Shares for Auction Limit-Down Prices and Turnover

Summary

This post describes an A-share selection rule that looks for stocks whose 9:15 opening-auction matched price was at the daily limit down on the previous session. It restricts candidates to a turnover range of 3% to 12% and excludes Beijing-listed shares. The accompanying Python example retrieves daily market data, identifies candidate limit-down opening prices, removes Beijing listings, and applies the turnover filter. The author presents the rule as an attempt to find stocks affected by weak market sentiment.

The rationale that such stocks could offer stronger long-run returns is asserted but not supported with performance results or a tested explanation. The post notes that the short observation window may miss promising stocks and that the screen omits other fundamental and technical information. It suggests supplementing the filters with measures such as valuation, profitability, or moving averages, and adjusting the observation window or decline criteria as conditions change. The code uses a fixed calendar interval and a simplified price comparison, so the document does not establish that the example is robust across dates or market regimes.

Key ideas

• The proposed screen selects stocks with a previous-session 9:15 auction price at the daily lower limit.
• It limits candidates to a stated turnover band and excludes Beijing-listed shares.
• The method is framed as targeting weak sentiment, but no evidence of subsequent returns is supplied.
• The post recommends adding fundamental or technical filters and adapting criteria to market conditions.
• The example uses a narrow historical window and does not demonstrate robustness.

Tags

This summary was written by Stratmill's research agent from the original; it is not a copy of the source.