Why basic data isn't enough when betting on MLB

Evidence of how much things can change in baseball

As baseball seasons go, 2018 has been defined by its imbalance. While the last four seasons have only seen four teams reach 100 wins and one suffer 100 losses, this year alone could come close (and exceed) those combined figures.

2014 – 2017 regular season records

2018 current and projected regular season records

Keep in mind those records were mostly accumulated before the trade deadline, when the good got better and the worst got worse.

Understanding why MLB is unique in betting

In addition to widely available data that can be used to inform the decision-making process in various fields (betting being one of the main beneficiaries), one of the biggest appeals of the MLB is that it is constantly evolving. Over the years there’s been countless shifts in how teams are managed and how the game is played, making it interesting and unpredictable.

MLB has effectively incentivised tanking in recent years – this is when a team endures a period of poor performance in the hope that it will result in much improved performance later down the line. The draft (which is common in most US sports) is an obvious reason for this with its worst finish gets first pick format, but MLB has also implemented a draft-slotting system that rewards poorer finishes with larger signing pools. Essentially, the teams that performed the worst are given greater resources and lesser limitations to work with.

The Chicago Cubs and Houston Astros are two recent and well-publicised examples of how tanking can ultimately lead to success. The fact that both teams won the World Series having struggled in the years prior was evidence enough of the benefits this approach can bring. Other front offices were quick to take note and implement something similar.

When Houston’s tank in 2011 resulted in a 2012 first pick, the Astros selected Carlos Correa over presumed #1 pick Byron Buxton and promptly signed Correa for less than the slot called for, presumably a pre-arranged deal. They used the left-over funds to sign supplemental first round pick Lance McCullers for more than the draft slot allotted. Thus, gaming the draft was born and the incentive to tank intensified.

Always consider the importance of the individual game

Billy Beane’s success with the Oakland A’s using a unique data-led approach built on Bill James’ notion of sabermetrics signalled an influx of analytically-minded executives in MLB front offices. Quantitative analysis, along with things like tanking, have brought with it a playoffs-or-bust mentality - with the incentives in place to lose, teams no longer treat playoff-irrelevant wins as important.

Over the years there’s been countless shifts in how teams are managed and how the game is played, making baseball interesting and unpredictable.

This means that when analysing upcoming games to bet on, it’s not just the strength of the opponent or what performance data might suggest that needs to be considered. Bettors should also be thinking about what the outcome of that specific game actually means to a team.

The concept of twisted motivations is a hard one to grasp in professional sport but it is evident in one form or another across the board – the Philadelphia 76ers “Trust the Process” and “Disgrace of Gijon” at the 1982 World Cup are just two examples that spring to mind. This is not a suggestion that teams will intentionally lose, but bettors need to be aware that they might be more motivated to win some games compared to others. 

Baseball is a rotation heavy sport. An MLB team has a 40-man roster from which to select their players (this comes from the active 25-man roster). Those new to betting may note that the starting pitcher is often listed alongside the odds for the game and (while some argue it is no longer as important as it once was) this shows the value that can be placed on specific individuals playing in a given game.

If the game you are looking to bet on doesn’t mean that much to one of the teams, it is likely that this will be reflected in the starting line-up - betting without having an in-depth look at each teams' line-up will cost you dearly.

How the MLB schedule can impact your analysis

Following on from the idea of approaching your baseball betting on a game-by-game basis, it’s also important to make team-by-team considerations as part of your analysis. Obviously, you require an elite level of skill to become a Major League Baseball player, but there’s a wide range of talent in the league and not all MLB players (and team line-ups) are created equal.

Different offences create different outputs and that means results against different offences mean different things. In the simplest possible terms, if pitcher X allows five runs against a Red Sox team that averages 5.41 per game and pitcher Y allows five runs against a Royals team that’s averaged 3.68 runs per game, the data on offer will show the same figures but pitcher X has obviously scored the greater accomplishment. 

Of course, runs per game is an awfully large sample and a metric that inaccurately characterises the team you’re betting on (or against). A number of factors need to be considered when assessing an offence (and therefore the starter who has faced them). 

Betting without having an in-depth look at each teams' line-up will cost you dearly.

Toronto is a mid-ranked MLB offence. Using the Fangraphs’ OFF ranking (a composite offensive metric), they are 38.7 runs below average. In the previous 30 day period from mid-August, the Jays are ranked 18th, the last 14 days 20th and the last 7 days 21st. As statistical samples go, the more recent the results, the more relevant and this past week will be a more-accurate representation of the team you’re betting on today than, say, the first week of the season would be. 

Pitcher-handedness is another factor that may seem like an obvious one to most bettors but it shouldn’t be overlooked. Some teams are better-able to handle pitching from one side or the other. The Jays rank just 18th in both wRC+ and wOBA against left-handers, but are 9th-best against righties. This is a great example of how the handedness of a starter should be influencing your bets.

Home field advantage is present in most competitive sports (some more than most) and baseball is certainly one of them. Toronto is 10th in wOBA and 13th in wRC+ when hitting at home, 13th and 12th respectively when away. Some teams, like the Rockies (with a stadium more suited to hitters) and the Padres (more suited to pitchers) enjoy broader ranges.

Another factor that bettors need to think about when trying to analyse the two teams competing in a single game is day vs. night. Using the Blue Jays as a point of reference again, they have a sOPS+ (day/night split OPS relative to the league, with 100 being average) of 97/109 for night/day. Again, this is far from an in-depth analysis but just goes to show how spending the time to delve a bit deeper into data can benefit bettors.