Scarb Glossary
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Tested — does not work

The pressure a sliced order puts on the book

A large order that a bot chops into pieces and feeds into the market really does push the book around. You just cannot get paid for that push: the move does not come back, and what is left to take is smaller than the fees.

Why it sounded right

You can watch the mechanism happen, and that is the strongest part of the idea. On some venues a large sliced order is public: you see the coin, the side, the size, and the window it has to be filled in. Then you watch the book and see each slice eat the top levels, the price jerk, and market makers refill a few seconds later. This is not theory. It happens on your screen.

The obvious conclusion follows. If a slice is bigger than the liquidity sitting above it, it pushes the price further than it should go. So right after a slice the price is too high, and you can stand against it — sell into where a buy just pushed. The idea rests on real microstructure, not on a pretty picture, which is exactly why it is easy to believe.

A second class of observation adds to the confidence. Sometimes the bot stops halfway through, and the price falls apart right after. That looks like a ready-made trade: the bot gave up, the bid is gone. One or two of those in a row convince you harder than any table.

How we tested it

First we collected the slices ourselves. For every sliced order we recorded the book and every trade, split the fill into slices, and for each one measured how far it pushed the middle of the market, how much of the liquidity above it it ate, and whether the price came back after half a minute, a minute, five minutes.

The main control was to strip out the market's own move. The first raw run showed a strong lopsidedness: standing against the sells paid, standing against the buys did not. That looked like a discovery. But most of the sample sat in one coin, and that coin was going up that day. So "standing against sells pays" just meant "being long on an up day." To subtract that, we stopped comparing against zero and started comparing against the same coin's move over the same window, counting it so that buys and sells cancel the general drift: if the effect is real, you see it on both sides. If you only see it on one, that is the market moving.

How it ended

The push is there. The snap-back is not. The bigger the slice relative to the liquidity available, the harder the price jerked — that held up firmly. But the return was negative: after a slice the price does not come back, it keeps going the same way. Which means the founding thought, "it got pushed, so it will bounce," is wrong at the root.

Once the market's own move was removed, what was left from standing against the slices was real but tiny — around the cost of a round trip in fees, or below it. On top of that, every slice has a dozen professional liquidity providers on the other side of you doing the same thing cheaper. A separate check also killed the pretty theory about the bot that stops: orders the bot carried through to the end did slightly better than the ones cut off halfway. Exactly the opposite of what the vivid case suggested.

What this teaches

More in this section

A long shelf, then a break upward
The idea: price sits in a well-worn range for months, and leaving it means a run to the next such range. When we tested it, breaking out of the shelf paid exactly as much as a random day on the same coin.
Big orders in the book as a reference point
The idea: a big order in the book is a level price will bounce off, or a level it will aim for. When we tested it, price reached such a wall no more often than it reached a randomly picked level at the same distance.
Buying into a vertical spike
The idea: the coin has gone vertical, so a move has started and you should get on board while it runs. When we tested it, buying the spike was not a zero but a loss: far fewer trades finished up than with a random entry.