Stock Screening with Price Range and Bollinger Band Position

Summary

The document describes a Chinese equity screening idea that combines a minimum daily price range, exclusion of stocks that hit the upper price limit on the previous day, and a closing price between the Bollinger middle and upper bands. It presents Bollinger bands as a way to contextualize price movement and gives a formula based on a moving average plus or minus a multiple of rolling standard deviation. A Python sketch uses a 20-session window and two standard deviations to calculate the bands.

The post offers no backtest, performance figures, or comparison against a benchmark, so it does not establish that the screen predicts gains. It also recommends adding technical and fundamental filters and diversifying the resulting holdings. The example code has apparent data and condition inconsistencies, including referenced fields not requested in its data query, so it should not be treated as a verified implementation. The screen is best understood as a proposed selection rule requiring careful data checks and independent evaluation.

Key ideas

• The screen requires daily amplitude above a threshold and excludes stocks that were limit-up on the prior session.
• It selects stocks closing between the Bollinger middle band and upper band.
• The example defines Bollinger bands using a moving average and rolling standard deviation.
• The post provides no performance evidence and notes that a narrow screen may reduce diversification.
• The sample implementation appears internally inconsistent and needs validation before use.

Tags

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