A record built for measurement, not for reassurance
A betting record written after the fact to feel better about results is worse than no record, because it looks like evidence. A useful record is written before the outcome is known, in the same fields every time, including the bets that lost.
§01The fields, and why each one exists
Every row should be written at the moment of the bet, before the outcome exists. A row added afterwards — even with honest intentions — is contaminated by knowing what happened.
- Timestamp. When the bet was placed, not when it was recorded. This is what makes a closing price comparison meaningful.
- Market and selection. Written precisely enough that the closing price can be found later for the same market, not a similar one.
- Price taken. The actual decimal price on the account, including any boost.
- Stake in units. In bankroll units, so the record survives a change in stakes.
- Your estimated chance. The number your decision was based on, recorded before the event. This is the field most people omit and it is the only one that can be audited.
- Closing price. Added later, once the market has closed.
- Closing line value. Computed from the two prices.
- Result and settling profit. For the record, not for the analysis.
§02Computing closing line value across a record
Two divisions and a subtraction, repeated. Convert the price taken and the closing price to implied chances, subtract the closing chance from the taken chance, and keep the result in points. Average across the sample, and track the average as a running figure rather than looking at any single row.
- Rows in the record
- 84
- Average taken chance
- 44.9%
- Average closing chance
- 44.0%
- Average closing line value
- +0.9 points
- Average price taken
- 2.23
- Average closing price
- 2.27
- Profit and loss
- −1.6 units
- What the record supports
- nothing yet — 84 bets is a mood, not a measurement
§03Reviewing a sample without lying to yourself
The purpose of a review is to change a process, so it should be scheduled and infrequent. Monthly is often enough, and reviewing after every bet is a way to generate conclusions from noise. When you do review, look at the things the record can support: the average closing line value, the distribution of your estimated chances against the de-margined market, and whether your losses cluster in markets where your estimate was least informed.
Do not review the profit and loss. It is in the record for completeness, and reading it as the primary output is precisely the mistake the rest of the record exists to prevent.
| Question | Answerable from the record? |
|---|---|
| Did I consistently beat the closing line? | yes — the average CLV |
| Was my process better in some markets than others? | partly — grouped by market |
| Am I a profitable bettor? | no — not from a recreational sample |
| Will this bet win? | not from any amount of record |
§04Rules that keep a record honest
Three rules make the difference between a record and a diary. Write the estimated chance before placing the bet, or leave the field empty rather than filling it in later. Log every bet, not the interesting ones, because selection bias in the record reproduces itself in the conclusions. And decide in advance what a bad month means — for most people, the honest answer is that a bad month means nothing at all.
The rule that matters most
If the record is only kept when results are good, it is not a record. It is a highlight reel with a spreadsheet attached, and its conclusions will be wrong in the direction that costs money.
Open the account you will actually measure
A record is worthless without a real price in the "taken" column, and the sponsored partner link below opens the account that supplies it. Whatever operator you use, check the terms and limits before you start logging, so the sample is not built on an account you lose access to halfway.
Affiliate disclosure and risk warning
Every affiliate link on this page and in the header is a sponsored link to a partner operator, and we may be paid if you open an account through it, at no extra cost to you. That link pays us; it does not price the market for you, and it is never a recommendation to bet. Nothing on this page is betting, financial or legal advice, and no price, model or result on it is a prediction. 18+ only. Betting is gambling: a measured edge is an estimate and the estimate can be wrong, the operator's margin is built into every price you are offered, and a selection with positive expected value can still lose — including many times in a row. Gambling can cause serious financial harm, including debt and damage to relationships and mental health. Never stake money you cannot afford to lose, never borrow to bet, and never increase a stake to chase a loss. Free, confidential support is available in most countries from national gambling-harm helplines, for bettors and for the people around them.