Ireland may be the most likely winners, but the forward-obsessed market is overvaluing Ireland's chances, says stats guru Jack Houghton...
"Wales, who host both England and Ireland at home in Cardiff, are the value at 6.005/1 to cause an upset…"
Elite sport has been transformed in the last few decades. Gone are the hard-living, part-time hobbyists, combining their sporting pursuits with other work, stress-testing their bodies with a schedule of socialising and sport that would fell lesser humans. They have been replaced with perfection-seeking professionals, optimising all aspects of their life - training, nutrition, recovery, rest - to ensure peak performance.
This revolution came later to Rugby Union, which only provided players the opportunity to profit from the sport in 1995. But it came quickly, too: with the sport now seen by many as one of the most far-sighted in terms of its use of sports science and technology.
Tactics, sabermetrics & analytics
These advancements are not limited to attempts to physically improve the players, either: they also seek a greater awareness of the tactical aspects of the game; aiming to provide players and coaches with quantifiable data that can be used to improve on-pitch decision-making. The best rugby operations in the world will slavishly analyse aerial footage of training and matches, and have developed sophisticated analytics which allow them to understand the tactical choices that will bring the most points (or concede the least) in the long-run. The sabermetrics revolution that transformed professional baseball at the turn-of-the-century (described in Michael Lewis' 2003 book, Moneyball) is beginning to flourish in elite rugby, too.
It's no surprise that the development of a statistical approach to player performance and decision-making has taken longer to find a foothold in rugby than it did in baseball, though. First, baseball has a long history of data collection, with avid fans having collated all manner of statistical titbits for generations. The development of sabermetrics, then, was a natural evolution, a refinement of which of the gathered numerical morsels provided the most insight. Rugby's statistical past is sparser.
Second, whilst baseball is a relatively static sport, with long periods of inaction and fewer variables that affect player and team performance, rugby is far more complex: a blistering try may seem to be the outcome of the shimmying speed of a winger, but might have more to do with a multitude of acts performed by rucking forwards in the minutes leading up to the try, drawing defenders out of position.
Despite the difficulty of the analytical task, though, the complex and seemingly chaotic game has been broken down into increasingly useful elements and, whilst much of this work is clandestine - jealousy guarded by professional outlets aware of the competitive advantages it brings - some of it is spilling over into the public sphere: the Guinness Six Nations website, for example, for the first time contains detailed information at a squad and player level on all manner of things, from the rudimentary (weight and height) to the microscopic (offloads made and missed tackles).
Punters are lapping up the new data
Punters are naturally drawn to such information, but the challenge when it comes to using any kind of data to inform betting decisions is knowing how that data translates into team performance, and what it tells you about the extent to which the odds available on a particular outcome represent value or not. As an example of this, for a few years I maintained a wildly-unprofitable Elo ratings system for international rugby, constantly refining it in the belief that it would bring punting profit. It didn't. I eventually abandoned the project, concluding that the limited number of international games, the long gaps between them, and the fluctuating motivations provided by different tournaments, meant that a model so successful in other sports would never work (for me, at least) for rugby.
Nonetheless, others are having more success in trying to make data predictively useful and, increasingly apparent in this work is that, whilst we may, as viewers, be drawn to the more flamboyant play of the backs, believing it to have the biggest influence on the outcome of a match, it seems to be the role of the front row and locks that is most pivotal. This is bad news for any team in the Six Nations that isn't Ireland or England, who can lay claim to some of the best forwards in the international game.
It's all about the forwards... especially Ireland's
Indeed, Maro Itoje, James Ryan, Devin Toner, Kieran Read, Tadgh Beirne, Dave Kilcoyne, Jamie George, and Cian Heeley top the best-in-the-world charts on a variety of playing metrics that indicate the positive influence they have on any game in which they play. Scotland's Ben Toolis is the only other forward from a Six Nations' team who inhabits the same statistical stratosphere as the other eight.
It's perhaps little wonder, then, that Ireland, boasting six of those eight, find themselves the 1.834/5 favourites for Six Nations glory. They are second in the world rankings, got the better of New Zealand in the Autumn internationals, and haven't lost a match since June 2018.
To add to their advantages, they have a favourable playing schedule. Various statistical studies have conclusively demonstrated that home advantage is significant in the Five/Six Nations, and has been consistently so. My own work suggests that playing at home in the Six Nations is worth something like five points in a match. Two of Ireland's away matches to Scotland and Italy - whilst clearly not walk-overs - are nonetheless the ones they would have likely chosen. Crucially, they are at home for their opening-match against England.
Wales, the value, lie in wait
Ireland's final match against Wales has the look of a showdown to it, though. Wales may not have many players who top the metrics charts (their best forward, Alun Wyn Jones, only just creeps into the top 30 on my, admittedly crude, analysis), but it doesn't seem to have hurt their play. They haven't lost since facing Ireland in the last match of the 2018 Six Nations and, with home advantage this time around, they will fancy their chances of upsetting those who have taken 3.6013/5 on an Ireland Grand Slam.
And this perhaps highlights the issues with the sabermetric-esque attempts to improve predictive rugby models: whilst such work has value in analysing past player performance, it is very difficult to convert this data into a prescient tool; at least not one that it is easy to apply a percentage chance to. Analytics might be changing the way viewers and commentators understand the contributions of different players to a team's performance, but they are also leading to market over-reaction: the broadsheets have been full of talk about how the forwards are now the pivotal players to focus on and so, naturally, punters have weighed in on those teams perceived to have the best forwards.
Ireland may well be the strongest teams in this year's Six Nations and the most likely winners, but I would be reluctant to weigh-in heavily at the odds. By my reckoning, whilst their odds of 1.384/11 to beat England in the opener look about right, they face a more difficult task thereafter, and should be around 2.206/5 for the tournament, and a little over 5.004/1 to manage the Grand Slam. The market is overplaying their dominance.
Wales, who host both England and Ireland at home in Cardiff, are the value at 6.005/1 to cause an upset. The match in Paris is a tough opener for them on Friday night, but they should be shorter than the 2.1011/10 on offer to disappoint the Parisian crowd. They can use a victory there to propel them to further Six Nations glory, where the broadsheet focus may well turn to the influence of the backs.
Back Wales in Winner market at 6.005/1