The Anchor Effect: Why Your First Price Poisons Every Trade That Follows

The First Price You See Wins

You pull up a market for the first time. The Yes is trading at 32¢. You do some quick math, decide that seems roughly right, and move on.

Three days later you check back. It's at 41¢. Your brain does something sneaky here — it doesn't ask *is 41¢ fair?* It asks *is 41¢ better or worse than 32¢?* And since 41 is worse than 32, the market feels expensive.

Congratulations, you've been anchored. That first number you saw is now the invisible center of gravity for every decision you'll make in this market. It didn't earn that status. It just got there first.

Why This Kills Returns

Anchoring makes you a systematically bad buyer of momentum and a systematically bad seller of decay.

When a market moves against your anchor, you feel like you missed it. When a market moves toward your anchor, you feel validated even if the fundamentals shifted. Neither feeling has anything to do with the actual probability of the event.

The worst version: you saw a market at 20¢, didn't buy, watched it run to 60¢, and now you literally cannot pull the trigger even though your honest read of the situation is 80¢. You're not evaluating the market anymore. You're negotiating with your past self.

The Fresh Eyes Test

Here's the drill I run when I catch myself anchored:

Close the market. Open a note. Write down what you actually think the probability is *before* looking at the current price. Force yourself to a number — not a range, a number.

Then open the market and compare. If the market is at 55¢ and you wrote 70¢, that's a trade. If you wrote 60¢, that's not a trade, no matter how strongly you felt about 20¢ three weeks ago.

This sounds obvious. Almost nobody does it. Everyone opens the price first and then works backwards to justify why it's wrong.

Anchoring to Other People's Prices

The anchor doesn't have to be your own. Kalshi and Polymarket disagreeing by 8¢ on the same event creates a two-way anchor problem — both prices feel like they contain information, when often one is just illiquid.

Same with sportsbook lines vs. prediction market prices. If DraftKings has a candidate at -200 and Polymarket has them at 60¢, one of those is dragging the other. Your job is to figure out which one is doing the work and which one is just copying. Don't assume the number that got there first is the number that's right.

The Reset Ritual

For any position you've held more than a week, do this once:

Pretend you just discovered the market. You have no position. Would you buy at the current price? Would you sell? Would you pass?

If the answer is *pass*, and you're currently holding a large position, that's a signal. Your position exists because of a decision you made at a different price with different information. It doesn't get to exist forever just because it exists now.

The Only Anchor Worth Keeping

Your probability estimate is the anchor. The price is the variable. Most traders get this backwards — they treat the price as the anchor and their estimate as the thing that flexes to accommodate it.

When the price moves, your estimate shouldn't automatically move with it. Sometimes the price moved because new information arrived, and yes, you should update. But sometimes the price moved because someone with more money than sense bought 50k shares in the middle of the night.

Know which one you're looking at. That's the whole game.