56% claimed, 48% real

On April 17, an r/sportsbook user posted side-by-side screenshots of Leans.ai's marketing page next to a hand-tabulated record from the public pick log. The marketing page advertised a 56% hit rate. The hand-tabulated record clocked in at 48%. The post hit the front page of the sub by the next morning.

A 2-star Trustpilot review on April 21 said the same thing in fewer words: "the numbers on the homepage do not match what I see when I follow the picks for a month."

Two-thirds of the comments under that Reddit thread accused Leans of fraud. We don't think it's fraud. We think it's the universal trap of advertising raw ROI without subtracting the juice — a trap every AI picks product on the market falls into right now, including some past versions of our own marketing.

This post is the math. It's also why we just shipped vig-adjusted ROI on /record — a number that is impossible to inflate the way raw hit rate can be.

What raw hit rate hides

Hit rate is wins divided by (wins plus losses). It ignores odds. A 56% hit rate sounds great. A 56% hit rate on -200 favorites is a money loser. A 53% hit rate at +100 is a money maker. The number tells you nothing on its own.

Our /record page has shown ROI alongside hit rate since the page existed. ROI is net units won divided by units risked, so it weights a -200 favorite the same way a +100 dog gets weighted in the denominator. Raw ROI is much harder to game than raw hit rate.

But raw ROI has its own trap.

What raw ROI hides

Imagine a picker who lays -110 on every game and wins exactly 52.4% of them. That picker has a positive raw ROI. Specifically, their raw ROI is roughly 0.0% — break even. Why? Because 52.38% is the breakeven rate at -110. The juice is the 4.55% the book takes when both sides are priced -110/-110. To beat the books, you need to beat the juice first.

Now imagine that same picker advertised "+0.4% ROI over the last 1,000 picks." That sounds like an edge. It's not. It's noise around break-even, and the variance band on 1,000 picks at 52.5% is wide enough to swallow the entire claim.

This is exactly the trap behind the Leans 56%/48% controversy. The marketing page presents a number that looks profitable. Stripping out the juice would have made it look much more like a coin flip with extra steps.

Vig-adjusted ROI

Vig-adjusted ROI is raw ROI with the average sportsbook hold subtracted. The math is straightforward in two cases.

Case 1: standard -110/-110 markets

For a -110/-110 two-way market, the implied probability on each side is 52.38%, total 104.76%. The book's hold is 4.55%. Vig-adjusted ROI subtracts that 4.55% from the raw number.

A picker with a "+0.4% raw ROI" over 1,000 -110/-110 picks has a vig-adjusted ROI of -4.15%. That picker is paying the book to pick games. The 0.4% raw is a measurement of variance, not edge.

Case 2: mixed markets with closing-line capture

Real picks aren't all -110/-110. They include props, totals at -120/+100, futures, parlays. Each market has its own juice. To handle that, we compute the per-pick vig from the closing decimal odds of each pick:

implied_prob = 1 / closing_decimal_odds
per_pick_vig = implied_prob * 200 - 100   // clamp to [0, 10]

For a -110 closer that returns 4.55%. For a -120 closer it returns ~9%. For deep longshot 3-way markets it can return more, which is why we clamp at 10% — a single outlier 3-way market can't hijack the average. Average across all picks in the window with closing-line data, and you get the observed average sportsbook hold.

We tag the metric with its basis on /record, so users can see whether the vig estimate came from real closing-line data (basis: closing_line) or fell back to the constant 4.55% when fewer than 10 picks in the window had closing snapshots (basis: constant_4_55). The label on the tile tells you exactly which one was used.

Why CLV beats hit-rate marketing

Closing Line Value is an even sharper test, and it's the single metric professional bettors trust most. CLV measures whether you got a price better than the consensus closing price. Positive CLV over a real sample (1,000+ picks) is much harder to fake than hit rate, ROI, or even vig-adjusted ROI, because the closing line is set by the entire market, not by your own marketing department.

Our /record page publishes CLV per pick, averaged per window, alongside hit rate, raw ROI, and now vig-adjusted ROI. Every pick links to a permalink with the original posted price, the closing snapshot, and the SHA-256 hash chain that proves the row hasn't been edited.

What honest stats look like

Here's the four-number combination we believe an AI picks product should publish, in this order:

1. Sample size. At under 50 settled picks, edge is invisible. At 1,500 a 54% true edge becomes statistically detectable. We tag every window with where it falls on that curve.
2. CLV. The single noisiest-resistant metric. Hard to inflate in any direction.
3. Vig-adjusted ROI. Raw ROI minus the juice. Survives the books or it doesn't.
4. Hit rate. Last on the list because it's the easiest one to mislead with.

Anyone marketing the four numbers in the opposite order — leading with a high hit rate, hiding the sample size, never mentioning CLV — is fighting the math.

The receipts

Every pick on NuroPicks is hashed with SHA-256 at post time. Closing odds are captured at tip-off. CLV is computed live. Vig-adjusted ROI is recomputed every minute the window changes. None of it is editable after the fact, by anyone, including us. The Postgres trigger that locks the rows would reject the UPDATE.

The four numbers above sit on /record and on each /record/sport/[sport] page. They're free. The ROI ex-vig metric specifically is what Leans.ai charges $299/mo to surface; ours is on the same grid as raw ROI, on every window, included in the free tier.

The Leans 56%/48% gap that lit r/sportsbook on fire on April 17 was a teachable moment for the whole category, not a Leans-only problem. Every AI picks product needs to publish vig-adjusted numbers, sample notes, and CLV — or stop advertising the rosy ones.

We chose to publish them. The link is in the next paragraph.

See the full record · Read the methodology · Verify a pick

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Entertainment, not financial advice. 21+. Past ROI or CLV does not predict future outcomes. If sports betting stops being fun, call 1-800-GAMBLER or visit our responsible gambling resources.