A good sports betting column should be backed by a profitable gambler with a proven track record. It should offer picks generated by a sophisticated and conceptually sound model. Most importantly, it should treat the subject with the seriousness it warrants.

This is not that column.

Instead, this will be an off-beat look at the sports betting industry-- why Vegas keeps winning, why gambling advice is almost certainly not worth the money, and the structural reasons why even if a bettor were profitable, anything they wrote would be unlikely to make their readers net profitable, too.

While we're at it, we'll discuss ways to minimize Vegas' edge and make recreational betting more fun, explain how to gain an advantage in your office pick pools, preview games through an offbeat lens (with picks guaranteed to be no worse than chance), and tackle various other Odds and Ends along the way.

Tracking the Unders

In 2022 and 2023, mass-betting the unders was incredibly profitable over the first 6 weeks and essentially just broke even after that. I hypothesized this year that maybe all we needed to do to make a killing was to start our "mass-bet the unders" strategy earlier in the season.

We desperately needed a win last week; mass-betting unders had lost money four of the last six weeks and merely broken even in the fifth. Week 10 was a welcomed relief, though; unders went 9-5, returning a 22.7% profit if you got all the lines I posted at -110 odds (which would work out to $31.82 if you put $10 on every game).

Our "$10 on every game" betting strategy is down exactly $80 in nine weeks since we started tracking. Our "start with $160 and allocate an equal amount of the remaining bankroll to every pick" approach, by contrast, is down $107.62.

Let's Talk About Those Lines

Every week in this space, I provide a table of "lines I'm seeing". I've discussed in the past how useless this is in practice for a picks column; Vegas can shade the odds on a given line to make it a better or worse bet than the spread itself would suggest, and if they cared about me (they certainly don't), they could even change lines in response to any inefficiencies I wrote about so by the time you read this column that inefficiency would be gone.

There's another way those lines are misleading, though; it acts like they're a monolith.

I get all of the lines I post here from nflgamedata.com, run by a guy named Lee Sharpe. I use that site because, while many sites want to keep their data in their own little silo, Lee is an open data evangelist; it's not just possible to scrape data from his pages, it's actively encouraged, and he goes out of his way to make sure everything keeps working. For someone like me who is working with NFL lines on a weekly basis, that's a massive boon. He even keeps a csv file of all of his data that anyone is free to access at any time.

Lee doesn't set the lines himself; he mostly gets them from Pinnacle sportsbook, but in cases where Pinnacle doesn't offer odds for a particular game, he'll find them from somewhere else. (As an aside, Lee gathers these lines for a "Confidence Pool" game he runs where participants assign confidence levels to specific game outcomes and see if they can outperform the Las Vegas lines. At the moment, just 37 out of 526 users are outperforming Vegas. The pool winners from the last three seasons rank 3rd, 133rd, and 487th, meaning 2 of the 3 participants who have won the entire thing before are trailing Vegas in 2024. Vegas is very, very difficult to beat.)

But different books will have different lines. One book might have a team at -3 while the other has them at -3.5. Even if two books both have a team at -3.5, maybe one is giving -105 odds on it while the other is giving +105 (meaning a win pays out more money on the latter book than the former). Lines and odds don't vary a ton from one book to the next (if they did, algorithmic bettors could place contradictory bets on opposing sites with the most favorable odds for each side and book a small but guaranteed profit). But these small variations are often the difference between a 52% bet and a 53% bet, and that difference is often the margin between a profitable week and an unprofitable week, which is why serious gamblers engage in "line shopping", or hunting for the best deal they can possibly find.

This site illustrates the kinds of variance you can expect in lines. The "Line I'm Seeing" for the game tonight is Philadelphia -4 with an over/under of 49.5. But at the time I'm writing this, I could get Philadelphia -4 (-110) from Caeser's sportsbook, or if I'd rather, I could get Philadelphia -3.5 (-120) from MGM's sportsbook. And while most sites are offering over 49.5 at (-110), it turns out I can get the over at (-102) on Fanduel at the moment.

How much does that matter? If we bet every under at -102 instead of -110, we'd currently be running a 2.4% loss rather than a 5.9% loss, which is the difference between "down $32.94" and "down "$80" (at $10 per bet). Given that we'd have wagered $1320 to this point (not all at once-- we'd have wagered the same dollar multiple times), a $47 difference isn't huge. But with a lot more money at stake, it can be much more significant.

And this is with relatively small shifts in odds. As I've mentioned before, the more of your money Vegas is willing to take on a bet, the sharper you should assume its odds are. That plays out here, too; these variances are much larger on bets with lower maximums. Totals and odds on player props, for instance, can differ quite substantially from one site to the next.

What's more, books will often deliberately add "juicy" odds on a lower-limit bet in the hopes that once you're in the door, you'll make several other more profitable (for them) bets as well. But the end result is that a substantial percentage of gambling profitably is just constantly shopping around for the best odds you can buy.

For recreational gamblers like us, it's not as big of a deal; we're losing money in the long run, but hopefully, we're having fun doing it. It's usually not worth spending 10 hours a week line-shopping to reduce our expected losses by $8 a week. Like a lot of things, once you do the math on costs and benefits you quickly discover that you've just invented a massively sub-minimum wage job for yourself.

But it might at least be worth keeping two or three different sportsbooks or betting apps handy and looking for the best odds you can find between them.

Lines I'm Seeing