A Stock Screen for Moderate Losses and Prior-Day Main-Force Control

Summary

This post describes a stock selection rule combining price amplitude above a stated threshold, a current-day maximum decline between four and five percent, and a condition described as main-force control on the previous day. It frames the screen as a way to consider price movement alongside a measure of large-investor activity. The accompanying code example checks a daily high-to-low ratio, a daily percentage change in that range, and positive net main-fund flow from the prior session.

The author cautions that the rule may overemphasize recent fund flow while overlooking company fundamentals, and that market sentiment can affect its results. The post suggests combining technical and fundamental analysis, but reports no backtest or investment performance. The wording of the amplitude threshold and the meaning of main-force control are not fully specified, and the supplied formula and code may not implement the written rule consistently. The selection logic is therefore an incomplete research idea that needs precise definitions and validation before practical use.

Key ideas

• The screen combines price amplitude, a current-day decline range, and a prior-day main-fund condition.
• The example code uses price-range and percentage-change checks alongside prior-session net main-fund flow.
• The post warns that recent fund-flow measures can distract from company fundamentals and market sentiment.
• The threshold wording and main-force condition are not fully defined, and the examples may differ from the stated rule.
• No backtest results or profitability evidence are included.

Tags

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