Halfway point summary - Team, period and score related data

Here is a summary of the Leafs scoring chance data I've been tracking so far this season. Data related to players is in another post. 

First, the team totals:

Overall				ES				PP				SH
ChF	ChA	Net	%	ChF	ChA	Net	%	ChF	ChA	Net	%	ChF	ChA	Net	%
655	815	-160	44.6%	505	630	-125	44.5%	141	17	124	89.2%	8	167	-159	4.6%

The second quarter of the season actually saw the Leafs improve marginally in terms of chances against, as the last 20 games have seen them at 45% at ES.

From extraskater.com, here are the Corsi data for the Leafs in the same situations:

Overall				ES				PP				SH
ChF	ChA	Net	%	ChF	ChA	Net	%	ChF	ChA	Net	%	ChF	ChA	Net	%
2121	2744	-623	43.6%	1596	2125	-529	42.9%	347	45	302	88.5%	25	409	-384	5.8%

The Leafs are now slightly outchancing their Corsi percentages, by about a percent and a half at even strength.

Game	Opp	Overall				ES				PP				SH
		ChF	ChA	Net	%	ChF	ChA	Net	%	ChF	ChA	Net	%	ChF	ChA	Net	%
22	NSH	19	18	1	51.4%	15	14	1	51.7%	4	0	4	100.0%	0	4	-4	0.0%
23	WAS	25	26	-1	49.0%	23	20	3	53.5%	2	0	2	100.0%	0	5	-5	0.0%
24	CLB	5	18	-13	21.7%	5	13	-8	27.8%	0	0	0	n/a	0	5	-5	0.0%
25	PIT	14	26	-12	35.0%	12	21	-9	36.4%	2	0	2	100.0%	0	5	-5	0.0%
26	BUF	16	19	-3	45.7%	14	13	1	51.9%	2	0	2	100.0%	0	6	-6	0.0%
27	MTL	12	26	-14	31.6%	10	19	-9	34.5%	2	3	-1	40.0%	0	4	-4	0.0%
28	SJS	19	20	-1	48.7%	11	14	-3	44.0%	8	1	7	88.9%	0	5	-5	0.0%
29	DAL	18	28	-10	39.1%	13	21	-8	38.2%	4	1	3	80.0%	1	6	-5	14.3%
30	OTT	15	27	-12	35.7%	12	19	-7	38.7%	2	0	2	100.0%	1	8	-7	11.1%
31	BOS	21	14	7	60.0%	16	12	4	57.1%	5	0	5	100.0%	0	2	-2	0.0%
32	LAK	24	11	13	68.6%	19	10	9	65.5%	5	0	5	100.0%	0	1	-1	0.0%
33	STL	10	26	-16	27.8%	8	22	-14	26.7%	2	1	1	66.7%	0	3	-3	0.0%
34	CHI	23	15	8	60.5%	20	13	7	60.6%	3	1	2	75.0%	0	1	-1	0.0%
35	PIT	19	19	0	50.0%	16	17	-1	48.5%	3	0	3	100.0%	0	2	-2	0.0%
36	FLA	16	16	0	50.0%	13	12	1	52.0%	2	1	1	66.7%	0	3	-3	0.0%
37	PHX	12	17	-5	41.4%	11	16	-5	40.7%	1	1	0	50.0%	0	0	0	n/a
38	DET	12	20	-8	37.5%	8	19	-11	29.6%	4	1	3	80.0%	0	0	0	n/a
39	NYR	19	23	-4	45.2%	15	15	0	50.0%	4	0	4	100.0%	0	8	-8	0.0%
40	BUF	26	21	5	55.3%	21	19	2	52.5%	5	0	5	100.0%	0	2	-2	0.0%
41	CAR	15	25	-10	37.5%	11	25	-14	30.6%	4	0	4	100.0%	0	0	0	n/a

Of course, something that you can't avoid when tracking these team numbers is score effects - these can substantially change the balance of chances between teams, as we'll see. So I've compiled some data based on periods and scores.

This period data considers only full strength play.

Period	For	Against	Ch%
1	156	200	43.8%
2	164	204	44.6%
3	150	198	43.1%
4	25	13	65.8%

The Leafs have roughly been the same in all three periods, but much better in extra periods. For some small comparison to overtime, the Leafs are at 7-15, ~32% at 'regular' 4-on-4.


What about score effects? First, I looked at 5-on-5 Close, which is defined as within a goal in the first two frames, and tied in the third.

State	For	Against	Ch%
5-on-5	470	602	43.8%
Close	295	372	44.2%

The Leafs are very marginally better in the close situations, but not by enough to indicate any serious difference.


Next, I asked myself about the Leafs ability to chase leads, versus their ability to defend leads, in the third period; I looked at all the chances generated for and against the Leafs in the 3rd period while the game was not tied, but within two.

State	For	Against	Ch%
3rd Chasing	47	46	50.5%
Down 1	31	27	53.4%
Down 2	16	19	45.7%
3rd Defending	54	83	39.4%
Up 1	35	54	39.3%
Up 2	19	29	39.6%

This is a pretty striking difference, and fits with my original idea, that the Leafs were under far too much pressure while defending leads, versus the amount they put on opponents (hardly surprising, given their overall struggles). Essentially, what the data says is that while chasing a lead in the third period, the Leafs have the same chance percentage that we would expect from an average NHL team (in fact, 50.5% is what extraskater gives as the median Corsi for all NHL teams 5-on-5), while they allow opponents to get more than 60% of chances when holding a lead. Of course, it's also important how the Leafs play at other times for comparison. The Leafs have been at 42.1% when the game is tied (data below). This suggests they don't actually do a whole lot worse when defending leads, though that's more a damnation of their regular 5-on-5 play than praise of their defensive efforts. We would expect the Leafs to face some substantial pressure when they have the lead late; after all, they're under pressure for much of the game anyway.


Next, an overall summary of the Leafs' performance at different score states.

State	For	Against	Ch%
-4	6	9	40.0%
-3	16	20	44.4%
-2	37	52	41.6%
-1	90	93	49.2%
Trailing	149	174	46.1%
0	168	231	42.1%
Leading	152	196	43.7%
1	103	129	44.4%
2	33	46	41.8%
3	12	9	57.1%
4	4	12	25.0%

The Leafs are worse when tied then when leading or trailing, and they are almost an NHL average team in terms of chances when down by one.


And next, the combination data,breaking down the data by both period and score.

Period	Margin	For	Against	Ch%
1	-2	2	10	16.7%
1	-1	24	40	37.5%
1	0	95	118	44.6%
1	1	32	31	50.8%
1	2	1	0	100.0%
2	-4	2	4	33.3%
2	-3	7	11	38.9%
2	-2	19	23	45.2%
2	-1	35	26	57.4%
2	0	46	75	38.0%
2	1	36	44	45.0%
2	2	13	17	43.3%
2	3	6	4	60.0%
3	-4	4	5	44.4%
3	-3	7	8	46.7%
3	-2	16	19	45.7%
3	-1	31	27	53.4%
3	0	27	38	41.5%
3	1	35	54	39.3%
3	2	19	29	39.6%
3	3	6	5	54.5%
3	4	4	12	25.0%

Of the states with  decent sample sizes (>20), the Leafs have been best trailing by one in the second, but what's really striking is how poor Toronto has been while tied in the second. They have been worse generating chances while tied in the second than while defending a third period lead. I'm not sure that this data has a whole lot of value, given that the sample sizes are beginning to get relatively small. What's really odd about this is that the Leafs have actually been above their overall average in every other state during the second period, making the period their best, despite the struggles while tied.

I've also put together some charts on the Leafs performances thus far, for those who like a little visualization:

Cumulative overall and ES chance percentages:





And 5-game cumulative stretches; there have only been a few brief periods all season in which the Leafs have been over 50%, and a couple of very poor runs down around 40%.




Next up, ST%. This is a net special teams performance, in essence the percentage of chances the Leafs get while on the ice at non-even strength. It's both indicative of how much time the team spends on powerplay versus penalty killing, and how effective they are at generating/preventing chances while those units are on.