Thursday, August 31, 2017

Picking Winners Straight Up vs. Against the Spread

I’ve often been told by people that they have no trouble picking the winners of NFL games, but that they don’t do well against the spread (ATS). They have a tough time believing me when I tell them that if they can pick the winner of the games, then they should be crushing the bookies by betting against the spread.

Here’s the proof:

The NFL sees 256 games a year. In the 2014 season, there was 1 game that ended in a tie and 3 games that saw the teams push ATS. Of the 252 games remaining, the winner of the game covered the spread 209 times. The winner covered the spread 82.9% of the time.

In the 2015 season 7 games that saw the teams push ATS. Of the 249 games remaining, the winner of the game covered the spread 214 times. The winner covered ATS 85.9% of the time.

In the 2016 season, there were 2 games that ended in a tie and 7 games that saw the teams push ATS. Of the 247 games remaining, the winner of the game covered ATS 213 times. The winner covered ATS 86.29% of the time.

Over the last 3 seasons, just picking the winner of the game would give a record of 636-112 ATS and a fantastic winning percentage of 85.0%.

The reason the number comes out so high is that when the favorite wins the game, they cover the spread a little more than 50% of the time, but when the underdog wins the game, they cover 100% of the time. That really messes with the numbers.

You see, it’s not so easy to just pick the winner of the game, otherwise we’d all be getting rich betting the money line, right?

Wednesday, August 30, 2017

Mistakes When Averaging

When people try to predict football games they often fall into a trap of their own making. That trap is called averaging. When two numbers are averaged together, they sometimes cause false results. When two teams are playing, many handicappers try to predict the final score so they can make an informed decision on which team to bet on. To arrive at a score they average the two teams together, comparing offense to the defense.  

Averaging two numbers when the numbers are on different sides of average works ok. The trouble happens when both numbers are on the same side of average. That may be a hard concept to visualize, but after a couple examples it should become clear.

The average number of points scored by a team in the NFL during the 2014 NFL season was 22.7  which can be rounded up to 23. If team A comes into the game scoring on average 34 points a game and team B comes in allowing 10 points a game, averaging the totals together gives a result of 22 points scored for team A. (34+10=44. Divided by 2 equals 22.) One team scores above the league average of 23 and the other team allows below the league average of 23, so that works well and gives a good result.  

If team C comes in scoring 34 points a game and team D comes in allowing 28 points a game, averaging the totals together would give a result of team C scoring 31 points, which is less than what they normally score. That just doesn’t make sense. Team C comes into the game with a really good offense that scores well above average, and when faced with a poor defense that allows more than average, why would they be predicted to score less than they normally do?

The problem is both teams are on the same side of the league average, which gives false results. It makes good teams seem worse and bad teams seem better. The fix is simple enough. Add the two scores together and subtract the NFL average to get a good prediction.

Using teams C and D, the better number is calculated like this:


 62-23(The league average.)=39.

 Where averaging gave a score of 31 for team C, subtracting the league average gives a score of 39, a huge difference of 8 points. To get consistently better results, don’t average numbers together to make predictions in the NFL.

Here’s a full game mock up to illustrate the difference. These numbers are just an example and we’ll use the Seahawks and Lions for the teams.

The Seahawks come in with a season average game score of 31-24, the Lions come in with a season average of 20-27. When using averaging, the result is a predicted score of the Seahawks winning 29-22. (31+27=58/2=29 for the Seahawks and 20+24=44/2=22 for the Lions.) When using the recommended method, the predicted score becomes Seahawks winning by 35-21. (31+27-23=35 for the Seahawks and 24+20-23=21 for the Lions.) Using the average, the Seahawks are predicted to win the game by 7 points. Using the correct method I’ve laid out, the Seahawks are predicated to win by 14 points.  If the Seahawks were a 10 point favorite, a handicapper could be fooled into thinking the Lions were a good bet if he averaged the numbers. Using the correct method, the Seahawks are the clear choice.

Averaging when comparing teams is a very common mistake and also one of the costliest. Be aware and beware.

Sunday, August 27, 2017


Bet Sizing

When it comes to betting on football games there are many systems out there. The most popular systems seem to follow the same basic idea. It goes along the idea of raising your bets when you’re winning and lowering them when you’re losing. That way you take full advantage of winning steaks and don’t get hurt on losing steaks. The reasoning behind this seems logical enough. That certainly sounds like good advice, but is it? It’s very bad advice actually. Before we get into the nuts and bolts of it, I have a simple question. How in the world does someone know they’re in the middle of a winning streak? And if they know that they’re in the middle of a steak, why wouldn’t they bet everything they have on the next game? After all, they would know they’re going to win the next game, because being in the “middle” of a winning streak means just that. That they’re going to win some more games in a row. The advice is silly on its face. As it turns out, that piece of advice has hurt far more gamblers than it’s helped. Raising and lowering your bet sizes actually makes it harder for you to win.
Here’s an example. Take any series of 10 bets with 5 wins and 5 losses. If you bet the same amount on every game, you’re going to break even, no surprise there. Now let’s look at a sequence of bets, raising and lowering after a win or loss. It doesn’t matter what the order is for these 5 wins and 5 losses. I’ll do two below. The one on the left is 5 wins followed by 5 losses. On the right, 5 losses followed by 5 winning bets. The bet size will be 10% of the total bankroll after the last bet. The bankroll stars out at $1000.


Bet size
Bet size

The first thing we notice is that both sequences end up losing money. Remember, when you bet the same amount on each game you start with $1000 and after 5 wins and 5 losses you still have $1000. When you change bet sizes, you end up with about $950. You’ve lost about $50 in both examples, picking the same games at the same win rate, 50%. The wins and losses can be in any order. As long as there are 5 wins and 5 losses the results will be the same, minus about $50. The second thing to notice is that when you juggle the bet sizes, you have to win at a higher percentage rate to make money. Where 50% was break even, when varying bet sizes it’s a higher number.

Notice that the vig wasn't accounted for in these examples, so in real world application your money goes even faster! There’s no doubt about it, raising and lowering your bet sizes makes it harder for you win money.

This doesn’t mean to never raise your bet or lower it. If you use a bankroll, my advice is to only change your bet size at the beginning of the season and keep it at that level for the whole season.  If you don’t use a bankroll, and you should, you should never change your bet size during a season.

Most gamblers don’t understand this concept and consequently make it harder on themselves to win. Don’t fall into this trap!




Friday, August 25, 2017


Win Percentage


What percentage of bets should a handicapper expect to win, against the spread (ATS),  during an NFL season? When I first started out 20 years ago on I asked friends and family that question. The answers I got most typically were around 70-75%. Even to this day when I ask people that’s about the response I get. That’s way too high of course. In fact 60% is too high, which surprises most people. 60% is very hard to achieve on a regular basis. The truth is, if a handicapper is winning at a rate of 60% long term, he’s probably not winning enough. That may sound confusing, but I should be able to clear it up by the end of this article.

There are two ways to judge how someone is doing with their picks. The first is win percentage and the second is how many units they’re ahead. Units are used as a measure and not money because people have different bet sizes and it’s difficult to compare directly with different amounts of money in play. When calculating units won, add 1 for every pick won and subtract 1.1 for every losing pick.

Let’s look at two gamblers and see how they did. The first person goes 4-2 has a fantastic win percentage of 66.7%. Another person goes 7-4, which is a 63.6% winning rate. A very good winning percentage, but not as good as the first one.  The fact the second person won almost 50% more units gets lost in the shuffle.  4-2 wins 1.8 units versus 7-4 which wins 2.6 units.

With that in mind, which of the two gamblers above did better? It depends on how you look at it. The first had a higher win rate. The second won more units. It may not be that the first person was better at picking winners, it might be that the second person bet on every game he thought he could win. If the goal is to make money, and that’s my goal, then it’s clear to see the second gambler did better.

The breakeven point on betting in the NFL is 52.38% (You have to win 11 games for every 10 you lose. 11 divided by 21 equals 52.38 %.) If you’re presented with two games to bet on, one that wins at a rate of 60% and another that wins at a rate of 55%, how should you bet? If you’re trying to play it safe and minimize your risks, you’d go with the 60% bet. However, the best play to win money is to bet on both games. While we’d all like to have a 60% chance of winning all our bets, those situations don’t come around all the time. To really make money in NFL betting you need to bet every game you have an advantage on. Any game, above say 54%, makes you money in the long run and if winning money is the goal, you should be taking advantage of every winning situation you can find.

If someone told you that they won $10,000 on betting football, are they a great handicapper? You'd have to ask a few questions. Like, how did they do it? If it turns out that this guy took all the money he had in the world and bet it on one game and won, I'd congratulate him. And then I'd walk away thinking this guy's an idiot.  But note, he won $10,000 and hit 100% of his bets! Does that make him a knowledgeable and great handicapper? Not in the least. It makes him lucky, very lucky, in the short run. Short run as in 1 bet.

 So what’s the answer to what should a handicappers win rate be? It depends on the amount of bets. If he is making just one bet he has to hit 100% to make money. If he’s making 200 bets, 55% makes him an 11 unit profit. As a general rule, the more bets you make the lower your winning percentage can be, because even a small winning percentage can show a nice profit given enough bets. A reasonable percentage to shoot for is 57.5%. Hitting 60% can be done, but if your win rate is that high you’re probably leaving money on the table by not betting all the profitable games that win at a lower rate. That costs you money to inflate your overall winning percentage. It can be a tricky balance.

If someone tells you they can hit 70% winners, run from that person as fast as possible! I’m not saying it’s impossible to do it for a season, however unlikely that is, but there’s no way to do it long term or to guarantee to be able to do it for the upcoming season. 

Tuesday, August 22, 2017

Who Pays the Vig?

Vig is short for vigorish, which is the amount of money that the bookmaker takes to handle wagering. It’s also called the juice. It’s how bookmakers make their money.

Who pays the vig when betting on football?  Even people who’ve bet football for decades get this completely wrong.

When a gambler bets on a football game, he bets 11 to win 10. If a gambler wins his bet, he wins $10. If he loses his bet, he loses $11. Who pays the vig, the winner of the bet or the loser? The answer almost every person will give is that the loser pays the vig by virtue of the extra dollar he pays.  However, this is incorrect. The winner pays the vig. The winner always pays the vig in games of chance, whether it be in the casinos, the lottery or in sports betting. The reason for this is that the loser of the bet always loses what he had at risk, no more, no less. The winner always receives LESS than the proper payout. The difference in what the winner should have been paid and what he received is what the bookmaker kept, which is the vig.

Let me give a simple example. If two friends decide to bet $11 on a football game, one wins $11 and the other loses $11. There’s no vig in play here. Let’s say the same two friends decide to bet another game, but this time with a bookie. Once again they both bet $11. When the game is over, one of them loses $11, just like in the first case. However the winner wins only $10, as the bookie keeps a dollar as his fee, which is the vig.  In both cases, the loser loses the same amount. It doesn’t matter to him if a bookie was involved or not. He loses what he bet. Does it matter to the winner if a bookie was involved? Absolutely! He wins $1 less when the bookie was used.

I once had a friend tell me that I had it all wrong, that I was playing with the numbers somehow. He tried turning things around. His reasoning went like this: If two friends decide to bet $10 on a football game, one wins $10 and the other loses $10. There’s no vig in play here. Let’s say the same two friends decide to bet another game, but this time with a bookie. When the game is over, the winner still receives $10, but the loser loses $1 extra for a total of $11. In both cases, the winner wins the same amount. It doesn’t matter to him if a bookie was involved or not. Does it matter to the loser if a bookie was involved? Absolutely! He loses $1 more when the bookie was used.

Can you spot the flaw in that reasoning?

What my friend forgot is that while the winner wins the same amount either way in his example, he risked more when the bookie was involved. He was still shorted $1 in the payoff, which is the vig. 

Remember, the loser ALWAYS loses everything he risks, no matter the game, no matter if a bookie or a casino is involved or not. The vig is always deducted from the winner and never added to the loser. The winner wins less than the correct payout. The difference between what the winner receives and what he should have been paid is the vig. 

It’s true that this knowledge isn’t going to save you any money or help you win more games. It should, however, serve as a warning of how little most people know about sports betting and handicapping, even those with lots of experience.