Choosing a trend filter you can explain aloud
If you cannot state the stand-aside rule in one sentence, the filter will not survive a noisy open.
A trend filter earns its keep when you can say it to a colleague without opening a chart. Examples we use in the lab:
- “No new long while the 100-day average slopes down.”
- “No new short while price closes above both the 20- and 50-day averages.”
- “Stand aside when the short average is inside a two-percent band of the long average.”
Complicated multi-condition gates look clever on a whiteboard and fail at 9:45 a.m. In Trend Filter Lab we score filters by how few false starts they allow over a shared historical packet — not by how many parameters they contain.
Write your rule on the top margin of every sheet you mark this month. If you keep amending it mid-session, the rule is not ready for capital.