Invalidation conditions in a trading plan: this dollar rebound as a case study
Translate “I was wrong” into concrete price, time and signal conditions.
Why invalidation conditions matter
Most trading plans specify an entry and a stop, but rarely state what would make the whole view invalid. The distinction matters: a stop caps the loss on a single trade, while an invalidation condition answers whether you should still be operating in the original direction at all.
Three types of executable invalidation
The first is a price condition. Using this dollar rebound as the example: if the dollar index closes below key support for two consecutive sessions, the view that the dollar remains strong is invalidated. A price condition must state whether it refers to the close or the intraday level, and how many days of confirmation are required.
The second is a time condition. If a trade does not advance in the expected direction within a preset period, the driving force is insufficient. One option is: if the first target has not been reached three sessions after entry, halve the position. The purpose of a time condition is to avoid tying up capital in a position that is going nowhere.
The third is a signal condition. For example: front-end Treasury yields turn lower, inflation expectations fall, or correlated assets stop confirming in the same direction. Signal conditions require the observation targets to be named in advance, otherwise it is easy to find evidence after the fact that supports your existing view.
Case study: an invalidation checklist for this dollar rebound
It could read like this. One: the two-year Treasury yield falls for three consecutive sessions. Two: US inflation expectations in the New York Fed survey drop below 3.6%. Three: the dollar index posts a weekly close below the previous swing low. Four: two consecutive employment releases miss expectations while hike pricing is revised lower. Two of the four triggering means the original view needs reassessment.
How invalidation differs from a stop
A stop is mechanical — hit it and you are out. An invalidation condition operates at the level of judgement — hit it and you re-analyse. They cannot substitute for each other. A stop without invalidation conditions makes it easy to keep re-entering against a direction that has already changed. Invalidation conditions without a stop leave the loss on a single trade uncapped.
Write it down and review it regularly
List invalidation conditions alongside entry, stop and target in the plan, and review them once a week. As the market environment changes, the invalidation conditions themselves need updating.