Three readings can be taken from the same gamma profile. Calls and puts apart give the walls — the biggest stack on each side, the bounds of the range. Calls minus puts give the majors — where the net leans, the pin and the acceleration zone. Calls plus puts give the absolute gamma strike — the mass, whatever its sign. The third one is often called a magnet. We wanted to know what it had actually done, so we measured it the same way as the other two.
As a level
The absolute gamma strike, with its cluster and the same persistence rule as the walls, held 63 % of the touches it received on the open-interest book and 61 % on the volume book — and a placebo line at the same distance held 63 % and 62 %. In the trade harness it never reached sixty events on ES; on NQ the playbook around it ran 1.15 against a placebo of 1.01, with the second half of the archive at 0.99. As a line to fade or to buy, it did not distinguish itself from any other line at that distance.
As a magnet
This is the claim the name carries, so we tested it directly: take the absolute gamma strike at 15:00 and measure how far the close ended from it. Against a placebo shifted a few strikes away it looked spectacular — the close finished within 0.12 % of it on SPX against 0.40 % for the placebo. Then we added the honest control: the spot price at 15:00 itself. The close finished 0.10 % from the 15:00 spot. The magnet did not predict the close better than “price stays where it is”, and the same was true at 13:00.
The reason is structural. Gamma peaks at the money, so the strike with the most gamma is, by construction, the strike nearest the price. A magnet that sits next to the price will always look like it attracted the close. That is not attraction; it is proximity.
What it is good for
- Knowing where the mass is. A strike carrying a large straddle is invisible to the net reading — calls and puts cancel — and to the walls when neither side leads. The absolute gamma read shows it.
- Knowing when the mass moves. Its trail on the chart shows the minute the heaviest strike jumped, which on a 0DTE chain is often the minute the day’s character changed.
- Reading the profile faster. One line for “where is the gamma”, before choosing which side of it to trade from the walls or the majors.