🧪 Lab Notes #1: Favorites, Underdogs, and the Secret Life of + and – Odds
“Price always matters. Even when the tacos are mid.”
🎬 Intro
Everyone knows who’s good.
The smart ones know what that belief costs.
Those little “–” and “+” symbols next to odds?
They’re not alien hieroglyphics, and you don’t need Tom Hanks breaking into the Louvre to read them.
They’re just price tags — the sportsbook’s way of saying,
“Here’s what we’ll pay you if you’re right.”
Learn that, and half your competition just flunked out.
🎭 Favorites vs. Underdogs: The Cast of Odds
Negative odds (–) = the favorite — expected to win more often.
Positive odds (+) = the underdog — expected to lose more often.
But sometimes, the script flips.
When odds are perfectly even — no favourite, no underdog — you’re looking at a true coin flip.
That’s +100, the cleanest line in sports betting.
Risk $100 → win $100.
A 50/50 shot.
📊 The Math:
Implied probability = 100 / (100 + 100) = 50%
(More on how and why this formula works next lesson — we’ll unpack it step by step.)
From there, it tilts:
–200 = heavy favorite (~67% chance to win)
–130 = smaller favorite (~54–55%)
+115 = slight underdog (~46%)
+250 = Long shot (~29%)
It’s the eternal story: David vs. Goliath.
Goliath is the “–” sign — big, expected, expensive to back.
David is the “+” — smaller, risky, but pays double if the slingshot lands.
Most bettors still run toward Goliath because comfort feels like strategy.
💡 Quick Rule of Thumb:
If it’s got a minus, you’re paying for safety.
If it’s got a plus, you’re getting paid for risk.
💵 Odds = Price = Payout
Odds aren’t predictions — they’re prices.
And every price tag tells you exactly what the book will pay you for being right.
Examples:
Bet $100 on –130 → win $76.92, not $100.
(Favorites cost more because everyone wants the comfort blanket.)Bet $100 on +115 → win $115 in profit.
(Same risk, bigger payout — belief gets expensive when it’s wrong.)Bet $100 on +250 → win $250 in profit.
(Huge reward… but you’re basically buying a lottery ticket in sunglasses, hoping no one notices you’re broke.)
Odds don’t lie — they just tell the truth in percentages.
Your job is learning to read the receipt.
🌮 Odds in Tacos
Let’s make it edible:
–130 = Grocery store tacos. Reliable, familiar, overpriced.
+115 = A new taco truck down the street. Slight gamble, likely delicious.
+250 = Your buddy texting you at 2 a.m. to try gas-station sushi.
Could pay off. Could also ruin your weekend.
The truth? Odds don’t care how hungry you are.
They just price the menu.
Sometimes you’re overpaying for grocery store tacos.
Sometimes you’re snagging street tacos worth double the price.
Either way — you’re just reading a price tag on probability.
The sooner you stop guessing and start translating, the sooner you stop donating.
🎬 The Story Beneath the Numbers
Sportsbooks write the script; bettors play the roles.
The favorite’s the big-budget studio film — predictable, polished, heavily marketed.
The underdog’s the low-budget indie that sneaks into theatres and steals hearts.
Your job?
Spot the scenes where the script doesn’t match the budget — the moments when the math missed the plot twist.
Odds aren’t predictions — they’re prices.
And every price hides a probability.
That’s what we decode next.
📊 Up Next
🧪 Lab Notes #2 — Implied Probability: The Hidden Math Behind Odds
Every price tag tells a story. In here, we test which ones are worth buying.
L.S. signing off ⚗️
Jared
Lead Scientist — The Prop Laboratory
🧪 Lab Glossary: Key Terms from This Lesson
Favourites / Underdogs — Favourites are teams or players expected to win (negative odds). Underdogs are the ones expected to lose (positive odds).
Odds (+ / –) — The sportsbook’s price tags. “–” means you risk more to win less; “+” means you risk less to win more.
Implied Probability — The percentage chance hidden inside the odds. It converts betting prices into true probabilities.
Even Odds (+100) — A 50/50 line. Bet $100 → win $100.
Price Tag Mentality — Understanding that odds reflect value, not predictions. Betting is shopping for mispriced probability.
Risk vs. Reward — The balance between payout size and likelihood of winning. Every bet lives somewhere on that spectrum.
2 A.M. Sushi Bet — A reckless, long-shot wager that feels genius until the sun comes up and your stomach reminds you it wasn’t. Usually +250 or worse.
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(An evolving index of every term, example, and concept from all Lab Notes & Field Studies— updated as the series grows.)
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