Never Apologize, Never Explain 2017-18

This page describes the methodology for this year's TBRW? Predictions.  As always if you catch an error please contact the humble author.

RS

RS is each team's points in the prior ECAC regular season:

	RS
Brown	7
Clarkson	23
Colgate	15
Cornell	31
Dartmouth	16
Harvard	34
Princeton	19
Quinnipiac	27
RPI	12
SLU	28
Union	34
Yale	18

PS

PS is the number of upset (lower seed) advances (+1) or eliminations (-1) in the previous season's ECAC tournament.  The consolation game is ignored.

The upsets in the last season's ECAC tournament were:

• #5 Quinnipiac upset #4 St. Lawrence
• #3 Cornell upset #2 Union

	PS
Brown	0
Clarkson	0
Colgate	0
Cornell	+1
Dartmouth	0
Harvard	0
Princeton	0
Quinnipiac	+1
RPI	0
SLU	-1
Union	-1
Yale	0

Imp

Imp is the difference in points gained in the second half (games 12-22) minus the first half (games 1-11) of the prior ECAC regular season, divided by 2, rounded down.  A positive Imp indicates the team had a better second half:

	Pts	2nd ½	1st ½	Diff	Imp
Brown	7	3	4	-1	0
Clarkson	23	10	13	-3	-1
Colgate	15	7	8	-1	0
Cornell	31	15	16	-1	0
Dartmouth	16	6	10	-4	-2
Harvard	34	19	15	+4	+2
Princeton	19	12	7	+5	+2
Quinnipiac	27	14	13	+1	0
RPI	12	10	2	+8	+4
SLU	28	10	18	-8	-4
Union	34	15	19	-4	-2
Yale	18	8	10	-2	-1

RP%: Returning Points Percentage

This year we are replacing the old methodology for estimating returning strength that combined forwards, defense and goaltending.  Instead we use a simpler statistic: the percentage of returning point scoring (RP%).  The old metric didn't seem to be doing a great job of predicting the fall-off due to departing talent.  The goaltending figure overwhelmed the other components.  The old measure had an arbitrary cutoff with relatively weak theoretical justification.  We intoduce another measure, RA (described later), to capture what is lost in this simplification.

The following players with eligibility remaining are not returning:

• + Spencer Foo, Union, F, Jr, 26-36-62
  + Sam Vigneault, Clarkson, F, Jr, 12-24-36
  + Nick DeSimone, Union, D, Jr, 9-10-19
  + Lou Nanne, RPI, F, Jr, 3-8-11

  
  

 RP% = Points Returning / Total Points from Prior Season

RA: Returning Awardees

Since returning scoring only captures the offense, we're also introducing as new metric, Returning Awardees (RA), to account for the return (or loss) of highly talented players.  RA is the net return (or loss) of ECAC First Team, POTY, and ROTY awards.  The potential repetition of players (e.g., First Team and POTY) is intentional to allow for the impact of unusually talented players,

The 2017 ECAC awardees were:

Award	Name	Team	Status
1st team	Foo	Union	Depart
1st team	Kerfoot	Harvard	Depart
1st team	Vecchione	Union	Depart
1st team	Bayreuther	SLU	Depart
1st team	Fox	Harvard	Return
1st team	Hayton	SLU	Depart
POTY	Vecchione	Union	Depart
ROTY	Fox	Harvard	Return

The calculation: add one point for each returning awardee while subtracting one for each departure:

	Return	Depart	RA
Brown	0	0	0
Clarkson	0	0	0
Colgate	0	0	0
Cornell	0	0	0
Dartmouth	0	0	0
Harvard	2	1	1
Princeton	0	0	0
Quinnipiac	0	0	0
RPI	0	0	0
SLU	0	2	-2
Union	0	3	-3
Yale	0	0	0

Avg10

Avg10 measures traditional program strength, by taking the team's mean number of Points over the prior 10 seasons.  This will be used to compute the expected Incoming factor.

	Brn	Clk	Cgt	Cor	Drt	Hvd	Prn	Qpc	RPI	SLU	Uni	Yal
2008	15	33	21	25	15	27	28	22	15	16	25	22
2009	10	20	17	29	24	24	28	21	13	26	20	32
2010	16	11	26	31	17	17	18	22	23	23	28	32
2011	18	19	11	24	26	15	24	19	24	13	36	35
2012	14	22	23	30	19	25	16	23	17	21	32	22
2013	20	19	15	19	22	14	20	37	27	22	24	25
2014	17	24	29	24	16	16	8	28	21	18	37	24
2015	13	19	26	22	26	25	6	35	18	29	17	28
2016	12	23	14	22	22	28	9	37	23	25	18	31
2017	7	23	15	31	16	34	19	27	12	28	34	18
Pts	142	213	197	257	203	225	176	271	193	221	271	269
Avg10	14.2	21.3	19.7	25.7	20.3	22.5	17.6	27.1	19.3	22.1	27.1	26.9

Summary:

	Avg10
Brown	14.20
Clarkson	21.30
Colgate	19.70
Cornell	25.70
Dartmouth	20.30
Harvard	22.50
Princeton	17.60
Quinnipiac	27.10
RPI	19.30
SLU	22.10
Union	27.10
Yale	26.90

Putting it All Together

Now we put everything together to predict the final standings.  This is a function of both the strength of returning players and an estimate of the strength of the new players.

The Past

Firsty, we want a measure of total returning strength, both the quality of the prior roster and its quantity -- the percentage of that roster returning.

Prior, the quality is the sum of RS, PS, Imp, and RA.

RP%,  the quantity, is simply carried down from above.

Past, the relative measure of returning strength, is the product of Prior and RP%.

The Future

Secondly,  we want to makew the same two estimates for the incoming player: their quality and quantity.

Avg10 is a proxy for quality we take the mean RS for the prior 10 seasons.

Inc%, the estimate of quantity, is simply 1 - RP%.

Fut, the relative estimate of incoming strength, is the product of Avg10 and Inc%.

Conclusion

All that's left to do is add Past and Fut together (Net), calculate a pro-rated normalization so the final prediction is against a mean of 22 points (Norm = 22 - mean of Net = 22-21.42 = 0.58), and then apply that normalizsation to produce our old friends, the predicted RS (Nieu) and standing (Pred).

Total: