Strengthening the Stats: Sometimes the Weighting Is the Hardest Part

Point Blank Thumbnail Monday

David Malinsky

Wednesday, October 11, 2017 1:56 PM GMT

Wednesday, Oct. 11, 2017 1:56 PM GMT

On the road to better stats, the process of "weighting" can be a valuable tool. ... Time to track those (Golden) Knight moves in Las Vegas. ... The Hector M. files are here.

Point Blank – October 11, 2017

No, I am not going to plug in another Tom Petty tribute on the jukebox to go with today’s headline because that would just be too cheap, and I do try to maintain standards here, admittedly with the bar set rather low. There will be more from Tom and the Heartbreakers on Friday, but following a weekend in which there were statistical idiosyncrasies galore, this is an opportune moment to bring some of the methods behind the madness (or vice versa) into play. This will also be the ideal prelude to Eagles/Panthers coming to the forefront on Thursday, and how to best record Cam Newton's 2017 performances.

As noted in the Monday edition, last week’s NCAA board brought such useless statistical gibberish as the California offense being penalized minus-41 rushing yards and the Washington defense being rewarded correspondingly for a bad snap on a field goal attempt that didn’t tell us a damn thing about either offense or defense. Western Michigan’s Jarvion Franklin ran for 104 yards in a seven-OT Win vs. Buffalo after regulation time had ended, which obviously required adjustment.

On Monday night, the Bears offense got credit for a 39-yard touchdown pass by punter Pat O’Donnell, and the Vikings defense was tagged with giving it up despite the fact that the Chicago offense and Minnesota defense weren’t involved in the play. And such is life when it comes to tracking football’s nuances.

Taking plays like that out of the tables is crucial to developing proper numbers and ratings, but it is also time consuming. The majority of you who read here each day likely don’t have time to keep your own stats, and even those who do may not have the time to sort through detailed play-by-play analysis. Don’t feel bad if you can’t do it – you are in the majority of bettors, and while it might feel somewhat hopeless to be working with flawed statistics, that is what most of the marketplace also has to deal with. And also take the time to understand that it isn’t that the flaws will keep you from winning – the fact that those flaws exist help to create opportunity.

There is one practical aspect of the process that I can address today, and it is a simple one for the do-it-yourself handicapper. Something I write here often, and discuss across other media platforms, is game-weighting. It is a basic fact of sport that not all outcomes deserve the same weight, teams going much harder in some games than others, and blowouts often having many of the minutes played by reserves, rather than the starters you hope to be tracking.

For those keeping all of their own numbers that can be done by not building some of the useless events into the database in the first place. But even those who do that are subject to error in entering each game, and many advanced handicappers who work from their own databases have those numbers imported from the official sources first. That takes us to today’s mini-lesson.

I do chart each game exactly the way the official sites do, so that there can always be a correction against input error. I will then break down the numbers across various key components, with a lot of deleting going on, before I have team/player stats that I am comfortable with.

For those who can’t do that step, and only have the official numbers to work from, you can still advance through weighting.

I am assuming that most of you who go through these exercises use Excel, and the process is a simple one. Have one file for each team that mirrors the game-by -game official stats, and then create a duplicate. File A can be imported from a stat site, or if you enter yourself double-checked against those sites for accuracy. It is File B that you can go to work with.

In File B you want to establish a weighting process for each game, so that even if you don’t have the ability to throw something out, you can keep it from junking things up too much. You can start with the base of “1”, and the majority of games will finish with that rating, especially in the professional sports. Games of little to no meaning can be kept so that your stats align with the official counters, but you can reduce their weighting in your ratings by assigning them a far lower value. This is easy to do for individual games, but if you have the time, it is even better to do it by category.

On a windy afternoon in the Midwest, Indiana held Charleston Southern to 0-for-10 passing on Saturday, naturally for zero yards. That is a tremendous statistical performance for the Hoosier defense, but also one that just doesn’t mean all that much in the grand scheme. If I give that a weighting of .2 (which I did), my base stats still align overall, but my adjusted stats will make that particular category from that game far less significant.

You don’t have to get too complex here – you can start slowly until you get comfortable, and then develop a rhythm. You can work with current form by attaching more weight to recent games, like a 1.1 or a 1.2. In college basketball, I often use 1.25 for conference games. When teams play games with key personnel out, especially an NFL QB, the numbers make much more sense if you do this: the Indianapolis Colts can have a “1” attached to games with Andrew Luck, and perhaps a .5 to the others (again, if you can go category by category it is better, allowing the defensive ratings to stand at full measure).

I hope this helps, and I hope I explained the concept clearly enough; feel free to ask questions through the comments section (grey balloon in the upper left) so that we can make the processes easier. I’ll be laying out some current NFL ratings from one of our prime contributors in a moment, but first a Las Vegas moment, and a little hockey.

 

Working on those Knight moves

No, I will not bring Bob Seger into the jukebox, either, because that is also too easy of a layup. But charting the early play of the first Las Vegas major professional franchise has been intriguing in terms of measuring the wagering behaviors, as always the ongoing search to see if some market edges could be found.

In the first two road games the Nevada money was mostly against the NHL's Golden Knights. As noted across the weekend comments thread, Las Vegas was an underdog in each game, and the highest lines to be found on the favorites were in this state, in some instances 20 cents above where the games closed at SBR's top-rated offshore sportsbooks.

Tuesday’s home opener brought different traffic, not just much heavier, but also inclined to back the home team.

Sportsbook        Open Close
Caesars              -115  -135
Coasts                 -115  -135
MGM                   -110  -125
Southpoint        -115  -125
Stations              -115  -135
Westgate            -110  -125
William Hill        -110  -130

But ...

Pinnacle             -109  -117

We do have to take a caution here because there were special circumstances, not only it being the first home game, but also the bettors being able to get behind a 2-0 team that had earned some trust. And perhaps most important of all were the heightened emotions around the city because of the recent tragedy, which was handled with the proper respect.

Does this become a bandwagon situation? I would not expect it to because of how unique Tuesday night was, but it will provide some interesting tracking. We might get a tell from the local shop stewards for Friday’s Golden Knights home game for Detroit – will they choose to open them a little higher than the non-Nevada markets, in anticipation of the Tuesday money returning?

Now back to the NFL, and a new weekly bonus feature.

 

The Hector M. files for Week 6

Long-term PB contributor Hector Mendez is one of those who does do his own charting and weighting across the NFL, and he is generous enough to share his numbers with us each week. His individual team power ratings are available from Tuesday’s comments section and here are the current breakdowns across the various categories:

You can find the Point Blank archive here.

And if you want to know when PB is ready to go each day, as well as following along for some of the most important Sports Betting news as in unfolds, make @Vegaspointblank a part of your routine.

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