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 touch on various other Odds and Ends along the way.
A Random Story To Begin
There's a story I've heard a few times about a college professor who wanted to teach her Statistics 101 students about randomness, so she divided the class in half. One half she told to flip a coin 100 times and record the sequence of heads and tails on the board. The other half she told not to flip a coin, but to simply invent a random sequence of heads and tails to write on the board.
She would leave the room while the groups performed this task, and the students would call her back when they were done. She would then look at the two sequences and guess which one was invented. In most tellings, there was some sort of added incentive at stake; perhaps it was a Friday, and if she failed to identify the fake sequence, the students would have no homework that weekend.
Invariably, she would be summoned back, would glance at the board, and within a few seconds would have correctly identified the fabricated sequence and sent the students home for the weekend with some onerous assignment to be turned in on Monday. Her secret? She looked for whichever sequence had the longest string of consecutive heads or tails... and guessed the other one every time.
Is This Story True?
Is this story "lowercase-t true"-- as in, did it ever actually happen? I doubt it. People love setting little didactic parables in college classrooms. My grandma lovingly forwarded me dozens that all invariably ended with "... and that student's name was Albert Einstein". (Either Einstein was the most argumentative undergrad in history or people just like attaching his name to morality plays because they feel it gives the story more weight; I'll let y'all form your own opinions as to which is more likely.)
But I like this story anyway because it's definitely "capital-T True". The human mind was designed as one of the most efficient pattern-finding machines in the known universe; it is temperamentally ill-suited to recognizing and understanding true randomness. When most people try to visualize random, they actually visualize alternating-- a series which never tilts too far in one direction or another before correcting. These kinds of sequences are the opposite of random.
Consider: if you flip a coin six times, there's only a 3% chance that all six flips come up the same. (The first flip is a freebie, and then there's a 50% chance with each of the five subsequent flips that you continue to match, so the chances are 0.5 ^ 5.) In this respect, a sequence of six straight heads or tails would be relatively unlikely.
But a string of 100 flips contains 95 different six-flip sequences (flips 1-6, flips 2-7, flips 3-8, and so on), which flips things on their head. While there's only a 3% chance of a specific string of six all being the same, there's a 95% chance that some string of six matches. There's about an 87% chance to get a string of seven consecutive matching flips in 100 trials, and even a slightly-better-than 50% chance to see a string of eight straight, but precious few first-year undergrads would be so bold as to mix a T-T-T-T-T-T-T-T run into their fictional sequence.
Most first-year statistics students might even be leery of writing a sequence of five straight heads or tails, but it's a virtual certainty (99.8%) that you'd get at least one such run in 100 actual coin flips. The lack of any such run is the deadest of giveaways.
This is the Capital-T Truth that this story hopefully conveys: true randomness is far streakier than most people would ever imagine.
Lessons for Gambling
From Week 8 to Week 17 last year, my picks against the spread in this column went 23-8-1. If I had a carefully considered betting system that I had worked hard on, I would absolutely have viewed such a streak as validation of all my work, proof that I had found one of the key threads running through the tapestry of the NFL, and I was successfully unravelling it.
But I don't have a carefully considered betting system that I have worked hard on. Around here, we mostly operate on memes and whimsy. Nearly a third of my picks during that stretch were made by a literal (pseudo)random number generator. As a result, it was very easy for me to see that stretch as what it truly was: randomness being streaky, as randomness is wont to do.
This is, as they say, why Vegas keeps building casinos. The overwhelming majority of bettors are 50/50 propositions (with Vegas making its profit almost entirely from creaming the vigorish off the top). But given enough time, every 50/50 bettor is a statistical certainty to go on a heater. And because the human mind is a pattern-matching machine nonpareil, we can usually invent a more compelling story to explain that heater than "true randomness is actually pretty streaky", which induces us to keep betting, believing we have an edge that we really don't.
(Because of selective memory, it's also usually easier to remember our hot streaks than our cold streaks, which keeps us betting long after we've fallen back below .500.)
The flip side of this is that even if someone does have a genuine edge, there's still a great chance that they'll sometimes go on unbearable cold streaks, just because weighted coin flips are still quite streaky. It takes a good deal of certainty to stick with a system that's hemorrhaging money just because you believe in the process so strongly.
Yet another reason why I'm so ill-suited to be a professional gambler. Personally, I'll just stick with memes and whimsy.