Six beliefs, checked
Six claims about uplifted prices that circulate often enough to be worth checking against the arithmetic. Each is stated as it is usually said, then measured against the ten samples.
- claims checked
- 6
- false
- 4
- partly true
- 2
- offers sampled
- 1,200
- mean uplift
- +15.3%
- prices reverted
- 14.4%
Of six common claims, four are false on the sample and two are partly true. The false ones all make the same mistake: treating the uplift as a change to the event rather than a change to the price.
The six, one at a time
1. A bigger uplift percentage means a better offer.
false The percentage is applied to the price. On a fixed stake the money is the difference between the two prices, not the percentage of them: +11.1% on 1.80 paid 2.00 on a 10.00 stake where +12.5% on 4.00 paid 5.00.
2. A boost improves the chance of the selection winning.
false The chance belongs to the event. The implied chance moves because the price moves, and it moves the wrong way: on the sample mean, 39.8% to 34.6%.
3. Staking more means getting more out of the boost.
false Staking more than the cap adds nothing. The added value was 2.00 at a 10.00 stake and 2.00 at a 100.00 stake on the same offer - 20.0% of the smaller stake and 2.0% of the larger.
4. The growing acca step compensates for the extra legs.
false The step grows from about +5.0% at two legs to +20.0% at five, while the implied chance of the slip falls by roughly a factor of eight. On the sample the added expected value per unit staked was roughly flat across leg counts.
5. A boosted price has been agreed and cannot change.
partly true It is held for the window stated and reverts only on the conditions named - 14.4% of the sampled boosts. Three of the four revert routes are ordinary market mechanics rather than decisions.
6. A boost is free money.
partly true It adds expected value with no stake of its own - 2.42 on the mean sampled offer. It is not free money in the sense that matters: it pays only when a selection wins, which on the sample was 45.2% of settled offers, and the same stake still carries the ordinary margin.
Why four of the six fail the same way
Claims 1, 2, 3 and 4 all treat the uplift as a change to the bet. It is a change to the price of the bet. Once that distinction is held, each of the four falls out of a two-line calculation: the price moves, the chance does not, the cap fixes the value, and the legs multiply the chance of losing.
A boost changes the price of a selection. It does not change the chance of it, the size of the stake that qualifies, or the number of legs that have to land.