Track CLV by recording the closing line for every bet alongside the price you wagered at. After 100+ bets, aggregate CLV tells you whether you're beating the market long-term. Consistent positive CLV is the most reliable predictor of long-term ROI, more predictive than short-term W/L record.
CLV (Closing Line Value) is the implied probability difference between the price you bet at and the price the line closed at. To track CLV: log every bet with date, side, your odds, and the closing odds at the same book (or de-vigged market closing). Compute CLV per bet as the implied probability difference. Aggregate over 100+ bets.
Short-term win-loss record is noisy. A 60% hit rate over 20 bets and a 45% hit rate over 20 bets can both come from the same true 53% edge — just different variance. CLV smooths over outcome variance by measuring the PRICE advantage you captured, not the outcome.
If you consistently bet at better prices than where the market closes, you have positive CLV. Positive CLV strongly predicts positive long-term ROI even when short-term W/L is noisy. Sharp shops grade pickers by CLV first, hit rate second.
Convert both your bet price and the closing line to implied probability. CLV = closing_implied_prob - your_implied_prob (for the side you bet).
Example: you bet Yankees -140 (implied 58.3%). Line closes at -160 (implied 61.5%). Your CLV = 61.5 - 58.3 = +3.2 percentage points. You got the side at a better price than the market eventually agreed to.
Negative example: you bet Yankees -160 (61.5%). Line closes at -140 (58.3%). Your CLV = 58.3 - 61.5 = -3.2 points. You overpaid.
Spreadsheet columns (minimum viable):
The closing line is the price at first pitch (MLB), tipoff (NBA), or kickoff (NFL). Three ways to get it:
After 200+ bets, slice CLV by:
Positive CLV doesn't guarantee positive ROI immediately. You can beat the closing line on every bet AND still lose 5 in a row due to outcome variance. CLV is the leading indicator; ROI is the lagging confirmation. After 500+ bets, your CLV and ROI converge.
If your CLV is positive but your ROI is negative after 200+ bets, you're sharper than the market but cold on outcomes; the gap will close with more bets. If your CLV is negative but your ROI is positive, you're getting lucky on outcomes despite being worse than the market; the gap will close negatively.
Every published pick has a closing line snapshot captured in analytics/line_movement.json. The analytics/clv_tracker.py module aggregates per-pick CLV and surfaces summary stats on the track record page. Pickers can verify the model's CLV record alongside the W/L record.
Track CLV by recording the closing line for every bet alongside your bet price. Calculate CLV per bet as the implied probability difference (closing_implied - your_implied). Log in a spreadsheet with columns for date, game, bet, your odds, closing odds, outcome, and computed CLV. Aggregate over 100+ bets for a reliable signal.
CLV is more important than win rate because short-term win-loss is noisy. A sharp bettor can be 8-12 down over 20 bets due to variance while still having strong edge. CLV measures the PRICE advantage captured, which smooths over outcome variance. Sharp shops grade pickers by CLV first because positive CLV predicts long-term positive ROI even when W/L is volatile.
Average CLV +2% or higher is elite (consistently beating closing market). +0.5% to +2% is solid sharp profile likely to clear vig long-term. 0 to +0.5% is roughly market (break-even). Negative CLV indicates losing to the market; strategy needs revision.
Three options: (1) manually screenshot the line right before game starts, (2) use an odds aggregator that logs closing lines automatically (Odds Shark, Action Network paid), (3) reference a sharp book's closing line (Pinnacle is industry benchmark for 'true closing price'). For most bettors, option 1 or 2 is sufficient.
Yes, in the short term. CLV is the leading indicator; ROI is the lagging confirmation. You can beat the closing line on every bet AND lose 5 in a row to outcome variance. After 500+ bets, CLV and ROI converge. If 200+ bets show positive CLV but negative ROI, you're sharper than the market but cold on outcomes — the gap closes with more volume.