What I am hoping, is much like the Statistical
Baseball Betting System it's a case of believing it's harder than it
actually is to come up with a model-based NHL system.
This method closely follows the Predicting
NBA Games With Home-Away Averages method that uses home and away
scoring averages, so it may be best used at the tail end of this season, or
possibly during a season that has a full schedule, as the sample size that we
have for the current season is extremely small, with most teams having played
between eight and 10 home or away games.
The
Method
The first thing you will need are
the home and away median scores, unless you're more comfortable using averages,
in which case you'll want to calculate the home and away average scores. As
I've often said, I prefer medians, as they are not influenced nearly as much by
one or two extremely high-scoring or low-scoring teams, not to mention they are
much faster to calculate.
Through games played Wednesday, Feb.
20, the median score for home teams was 2.75 goals and they allowed 2.54 goals.
If you're looking at it from the road team's point of view, then it's obviously
2.54 goals scored and 2.75 goals allowed per game.
Next, look at the home or away
scoring for the two teams involved in the game you want to handicap.
For this example, we'll use Vancouver at Dallas and see the Canucks are
averaging 3.0 goals in road games and allowing 2.3, while the Stars are
averaging 3.2 goals in home games and allowing 3.0.
The next step is to divide each
team's scoring averages into the league median so that you get a percentage
that tells you how each team does compared to an average team.
Vancouver's 3.0 goals scored divided
by the median goals scored by road teams of 2.54=1.181 and the Canucks' 2.3
goals allowed divided by median goals allowed by road teams of 2.75=.836.
For Dallas, we'll do the same thing,
but this time be dividing into the median scores of home teams, so that Dallas'
3.2 divided by 2.75=1.164 and the Stars' goals allowed of 3.0 divided by
2.54=1.181.
The next step is to multiply each
team's offensive percentage by the opposition's defensive percentage and then
multiply that by the median number of goals scored for teams on the road, for
the visiting team, or at home, when you are calculating the predicted number of
goals scored by the home team.
For Vancouver, you will multiply its
offensive percentage of 1.181 by the Stars' defensive percentage of 1.181 by
the median number of goals scored by road teams, which is 2.54. So for the
Cauncks you have 1.181*1.181*2.54=3.543, which is the team's predicted number
of goals for the game.
For the Stars, you have
1.164*.836*2.75=2.676, which is Dallas' predicted goals in the game.
Calculating the total
is easy enough, as you simply add 3.543 to 2.676 and you'll get 6.219 or 6
goals. As there is a .219 remainder you could consider the predicted total as
being 6-over.
So take each team's predicted goals
and square that number. Vancouver's 3.543 becomes 3.543*3.543=12.553 and
Dallas' 2.676*2.676=7.161.
If you remember back to Pythagorean
Formula and Basketball Betting the next step is to divide the larger
of the two numbers into the sum of the two numbers, or divide 12.553 by
(12.553+7.161=19.714) 19.714 and 12.553/19.714=.637, meaning Vancouver has a
63.7% chance of winning the game.
To convert a percentage into a money
line, subtract your percentage from 1 and you get .363. Divide the larger
number by the smaller number and .637/.363=1.754 or -175. Therefore our line on
the game is Vancouver -175 with a total of 6, or 6-over, if you prefer.
The posted odds were Vancouver -150
with a total of 5.5-under, so you would have a lean to the over, but probably
not enough of a cushion to make a play.
