Anchoring: How First Prices Shape Your Thinking

## The Anchoring Effect Anchoring is the cognitive bias where the first piece of numerical information encountered disproportionately influences subsequent judgments. In betting, the first price you see for a selection becomes an anchor that shapes how you evaluate subsequent prices. ## How Anchoring Operates in Betting **Opening line anchoring:** A bookmaker opens Team A at 2.50. You immediately think "2.50 for Team A." When you later check Pinnacle and see 2.30, you interpret it as "expensive" — even if 2.30 more accurately reflects the true probability. **Personal prediction anchoring:** You estimated Team A's win probability at 45% before seeing any market prices. When the market shows 38% implied probability, you see "value" — but the anchor (your 45% estimate) may itself be biased, and the 38% may be the more accurate figure. **Round number anchoring:** Odds of 2.00 feel like a natural "fair" point. Bettors evaluate 1.90 as "short" and 2.10 as "generous" relative to this anchor — regardless of whether 2.00 was ever the actual fair price. ## The Professional Counter **Blind probability estimation:** Before looking at any market price, estimate your probability for each outcome. Write it down. Only then look at the market price. This prevents the market price from anchoring your probability estimate. **Price-agnostic model output:** Build your betting model to output probabilities only — not prices. Convert to implied prices only at the comparison stage. This keeps the model uncontaminated by market anchoring. **Multiple reference points:** Never rely on a single bookmaker's price as the reference. Always check Pinnacle, the exchange, and at least one alternative bookmaker to establish a range rather than a single anchor. ## The Anchor Test If you find yourself thinking "that's good value" or "that's short" about a price: ask what probability you assigned before seeing any market. If you did not assign a probability before looking at the price, you may be evaluating value relative to an arbitrary anchor rather than an objective estimate.