Let’s break down some common myths in this article!

1. “The house always wins” so they must be really accurate

A commonly believed myth is that because sportsbooks are making profit, they must have really accurate predictions. Well to sum it up, they don’t!. Sportsbooks actually make a large portion of their money on something known as the “vig”. There are 2 types of main outcome based bets: the winner, and the spread. I will focus mainly on the spread as a large majority of NFL bettors are betting spread. To sum it up, the goal of a sportsbook is to have 50% of people bet on each side, and they charge a “commission” fee such that no matter who wins, the house always does.

Spread is a bias such that the team must win by more than X points to cover an X spread. For example, if the Team X is -4 against the Team Y, for the bettor to win, Team X must win by more than 4 points (e.g. If Team X only win by 3, the better still loses if he bet Team X -4). Sportsbooks will open these spreads (commonly also known as “lines”) one week prior to the game being played, and based on the general populations choice, the line will be shifted in that favor in order to ensure as close to 50% of people are on each side of this spread. Each side of the spread will usually have -110 odds, meaning for every 11$ you put in, you get 10$ back if you win (plus the 11$ you placed the bet with). Because of this, sports-books will always make a 5% margin on these bets no matter what (10% of the losing side of the bet, which corresponds to 50% of people).

For this reason, sportsbooks don’t actually care how good their spreads are (to a certain extent)! Since 2002 , more than 28% of games have had the spread be wrong by over 6 points! This means they are not very good.

2. To make money, you must be predicting 70%+ of games correctly

Wrong again! Sports betting is a fairly new industry with a lack of regulations. For this reason, many people will claim an insanely high win rate on games that are absolutely unrealistic in order to pay people for their picks. The truth is, while still incredibly difficult, the margin required to have a long term positive profit if betting on spreads, is to win above 52.38% of your bets (the math behind this can be derived here). For reference, my current models that are based on spread are achieving around 55% win rate, so this indicates potential for large long term profits.

3. It’s incredibly difficult to consistently beat sportsbooks.

Saving the best for last. This is another common myth that can easily be disproved with one of the most simple strategies: betting purely on home underdogs (spread based bets). A recent piece of research shows that over the span of 10 years , the cumulative win percentage by betting purely on home underdogs is 53.5%, which is again above that important 52.38% threshold (albeit barely).

To sum up everything:

1. Based on how sportsbooks achieve their earnings, their models don’t actually have to be very accurate

2. To win against the spread, you have to beat the 52.38% winning ratio in the long run. My models over the course of the last 2 seasons are achieving ~55% win rates.

3. It isn’t incredibly difficult to profit off the NFL.

So the house always wins, but so can you!!