Expectations & the Spread

Let's talk more about expectations, specifically how teams have done against the spread this decade.

The first thing to realize, if you don't already, is that the spread is NOT a measure of how much Vegas thinks a team is going to win or lose by. It is a measure of what Vegas thinks the betting public thinks a team is going to win or lose by. Their goal is to get the number of bets on either side of the line as close to equal as they can, thereby ensuring that they'll win as much as they lose, making a profit on the vig they charge to place the bets. So it's in their best interest to know not only how good teams are and how they match up, but more importantly what the betting public thinks of how good teams are and how they match up.

So the spread can be seen as the mean, or middle, of public expectation. Half the people think a team will beat the spread, the other half don't. Looking at how teams have performed against these expectations can give us a good idea into whether they're truly underrated, overrated, or rated just about right.

In looking at all the data, some interesting things pop out. Things such as...

• There's a vague correlation between the percentage of time a team is the favorite and the percentage of time they beat the spread. It's very general, but teams that are favored more than 70% of the time cover 52.8% of the time, 60-70% cover 50.6%, 50-60% cover 49.8%, and on down.

• Texas, USC, and Oklahoma are the only teams to have been favored in 100 games or more, while Duke and Buffalo are the only teams with nine full seasons to have been favored less than 10 times.

• Only 6 teams have won less that 50% of the games in which they were favored (W. Kentucky, Duke, Idaho, Kent, & Vanderbilt), while conversely only 4 teams have won more than 50% of the games in which they were underdogs (Texas, Utah, USC, and Oklahoma).

• Amazingly, Utah has covered the spread 20 of the 24 times they were the underdog. When Baylor happens to be the favorite, they've covered 80% of the time (followed closely by San Jose State at 78%).

• Notable Overrated Teams (covering less than 45%) include... Washington (36.4%), Alabama (42.3%), Fresno State (42.9%), Michigan State (43.5%), and Clemson (44.2%).

• Notable Underrated Teams (covering more than 55%) include... Boise State (63.0%), Iowa (58.9%), Oregon State (57.3%), Connecticut (55.8%), and Louisville (55.7%).

• Conference-wise, the BigEast and Pac10 are often underrated, covering the spread around 55% of the time; the Big12, SEC, and MtnWest are rated about right, covering 50% of the time; and the Big10, WAC, SunBelt, and CUSA are overrated, covering around 45% of the time.

So on to the table. Here's the trickier headers breakdown:
W-Fav/W-dog = # of times they won when favored/underdog
cov/cov% = # of times spread covered/% of time spread covered
Avg Fav/Avg Dog = average number of points favored by/underdog by
all % covered = percentage of all favored or underdog games covered

Against the Spread, 2000-2008
Team	# gms	% Fav	# Fav	W-Fav	Fav W%	cov	cov%	# Dog	W-dog	Dog W%	cov	cov%	Avg Fav	Avg Dog	all %cov
Boise St	108	84.3%	91	86	94.5%	57	62.6%	17	5	29.4%	11	64.7%	-18.2	7.9	63.0%
Utah	107	77.1%	81	59	72.8%	42	51.9%	24	14	58.3%	20	83.3%	-11.3	6.6	59.0%
Iowa	109	55.1%	59	46	78.0%	34	57.6%	48	19	39.6%	29	60.4%	-13.3	7.6	58.9%
Oregon St	105	64.1%	66	51	77.3%	39	59.1%	37	12	32.4%	20	54.1%	-8.3	9.5	57.3%
USC	115	90.1%	100	86	86.0%	55	55.0%	11	6	54.5%	8	72.7%	-17.3	3.5	56.8%
Florida	112	84.7%	94	76	80.9%	52	55.3%	17	7	41.2%	11	64.7%	-16.4	6.0	56.8%
Oregon	109	68.5%	74	56	75.7%	39	52.7%	34	17	50.0%	22	64.7%	-11.2	6.1	56.5%
BigEast	338	63.6%	215	175	81.4%	121	56.3%	119	41	34.5%	67	56.3%	-13.7	9.7	56.3%
Texas	114	92.1%	105	90	85.7%	57	54.3%	9	6	66.7%	7	77.8%	-19.3	4.9	56.1%
Oklahoma	120	85.8%	103	92	89.3%	56	54.4%	17	9	52.9%	11	64.7%	-20.1	4.9	55.8%
Connecticut	95	41.1%	39	32	82.1%	22	56.4%	56	14	25.0%	31	55.4%	-10.2	13.3	55.8%
Louisville	108	77.4%	82	65	79.3%	46	56.1%	24	10	41.7%	13	54.2%	-15.9	8.0	55.7%
San Jose St	100	28.6%	28	24	85.7%	22	78.6%	70	12	17.1%	32	45.7%	-7.7	15.1	55.1%
Pac10	320	65.9%	211	170	80.6%	111	52.6%	105	35	33.3%	63	60.0%	-13.4	9.0	55.1%
Ball St	100	36.0%	36	29	80.6%	21	58.3%	64	17	26.6%	34	53.1%	-9.4	16.3	55.0%
Troy	81	42.5%	34	25	73.5%	16	47.1%	46	11	23.9%	28	60.9%	-11.0	17.1	55.0%
S Florida	83	58.5%	48	35	72.9%	27	56.3%	34	12	35.3%	18	52.9%	-9.7	11.5	54.9%
N Illinois	99	59.8%	58	43	74.1%	29	50.0%	39	11	28.2%	24	61.5%	-12.4	9.9	54.6%
Boston Coll	111	65.7%	71	56	78.9%	36	50.7%	37	18	48.6%	23	62.2%	-12.0	7.7	54.6%
Rutgers	101	36.4%	36	26	72.2%	18	50.0%	63	16	25.4%	36	57.1%	-12.0	14.7	54.5%
Ohio St	112	84.8%	95	82	86.3%	53	55.8%	17	7	41.2%	8	47.1%	-13.5	5.2	54.5%
Virginia Tech	113	83.0%	93	74	79.6%	47	50.5%	19	9	47.4%	14	73.7%	-15.5	6.7	54.5%
Navy	102	43.0%	43	33	76.7%	22	51.2%	57	16	28.1%	32	56.1%	-10.4	11.6	54.0%
Rice	105	33.3%	34	22	64.7%	16	47.1%	68	20	29.4%	39	57.4%	-8.3	14.1	53.9%
Northwestern	106	34.3%	36	27	75.0%	16	44.4%	69	24	34.8%	40	58.0%	-8.2	11.3	53.3%
New Mexico	106	42.9%	45	31	68.9%	22	48.9%	60	22	36.7%	34	56.7%	-6.9	8.1	53.3%
Toledo	103	56.9%	58	45	77.6%	34	58.6%	44	16	36.4%	20	45.5%	-13.3	7.4	52.9%
Syracuse	105	38.5%	40	28	70.0%	26	65.0%	64	12	18.8%	29	45.3%	-8.6	14.4	52.9%
Cincinnati	108	53.7%	58	43	74.1%	26	44.8%	50	18	36.0%	31	62.0%	-9.1	9.9	52.8%
TCU	108	73.1%	79	68	86.1%	41	51.9%	29	13	44.8%	16	55.2%	-13.9	7.7	52.8%
UCLA	111	60.0%	66	43	65.2%	30	45.5%	44	16	36.4%	28	63.6%	-8.8	9.2	52.7%
Buffalo	104	08.7%	9	7	77.8%	4	44.4%	94	18	19.1%	50	53.2%	-5.7	17.0	52.4%
Maryland	106	50.5%	53	42	79.2%	27	50.9%	52	21	40.4%	28	53.8%	-12.7	8.3	52.4%
Nevada	106	41.0%	43	34	79.1%	26	60.5%	62	13	21.0%	29	46.8%	-9.3	13.9	52.4%
California	109	62.6%	67	50	74.6%	34	50.7%	40	11	27.5%	22	55.0%	-12.9	9.9	52.3%
Temple	101	17.0%	17	12	70.6%	8	47.1%	83	10	12.0%	44	53.0%	-7.3	19.0	52.0%
Stanford	102	27.5%	28	18	64.3%	15	53.6%	74	21	28.4%	38	51.4%	-8.4	11.8	52.0%
Missouri	105	60.6%	63	46	73.0%	34	54.0%	41	9	22.0%	20	48.8%	-13.0	11.0	51.9%
Hawaii	109	61.3%	65	55	84.6%	34	52.3%	41	9	22.0%	21	51.2%	-14.3	12.5	51.9%
Texas Tech	108	67.6%	73	58	79.5%	38	52.1%	35	11	31.4%	18	51.4%	-13.1	10.6	51.9%
Auburn	108	68.5%	74	60	81.1%	36	48.6%	34	14	41.2%	20	58.8%	-13.7	6.2	51.9%
NC State	103	51.5%	52	32	61.5%	20	38.5%	49	20	40.8%	32	65.3%	-8.9	8.2	51.5%
Air Force	103	52.5%	53	34	64.2%	26	49.1%	48	18	37.5%	26	54.2%	-9.1	7.5	51.5%
Kansas St	105	68.6%	72	50	69.4%	36	50.0%	33	7	21.2%	18	54.5%	-15.8	9.1	51.4%
Penn St	108	65.4%	70	53	75.7%	37	52.9%	37	10	27.0%	18	48.6%	-13.6	7.4	51.4%
Georgia	110	79.8%	87	73	83.9%	43	49.4%	22	11	50.0%	13	59.1%	-12.1	5.3	51.4%
Big12	395	74.4%	294	244	83.0%	158	53.7%	100	26	26.0%	44	44.0%	-17.4	7.9	51.3%
LA-Monroe	91	16.7%	15	8	53.3%	6	40.0%	75	16	21.3%	40	53.3%	-6.9	17.0	51.1%
Kansas	100	37.8%	37	30	81.1%	24	64.9%	61	13	21.3%	26	42.6%	-10.9	14.3	51.0%
Mid Tenn St	98	51.0%	50	36	72.0%	25	50.0%	48	9	18.8%	25	52.1%	-9.9	14.6	51.0%
E Carolina	109	44.3%	47	30	63.8%	20	42.6%	59	17	28.8%	34	57.6%	-8.1	11.1	50.9%
Miami (OH)	108	54.6%	59	42	71.2%	30	50.8%	49	14	28.6%	25	51.0%	-12.2	8.6	50.9%
Kentucky	101	32.7%	33	24	72.7%	17	51.5%	68	13	19.1%	34	50.0%	-9.3	12.2	50.5%
S Carolina	105	49.5%	51	44	86.3%	28	54.9%	52	12	23.1%	24	46.2%	-11.5	7.1	50.5%
SEC	398	75.1%	299	245	81.9%	147	49.2%	94	36	38.3%	51	54.3%	-17.0	7.5	50.4%
Wake Forest	105	43.1%	44	32	72.7%	17	38.6%	58	20	34.5%	34	58.6%	-8.2	10.6	50.0%
Oklahoma St	102	43.1%	44	37	84.1%	29	65.9%	58	13	22.4%	22	37.9%	-15.3	10.0	50.0%
Bowl Green	103	58.8%	60	45	75.0%	29	48.3%	42	12	28.6%	22	52.4%	-13.6	10.2	50.0%
C Michigan	102	38.2%	39	30	76.9%	21	53.8%	63	12	19.0%	30	47.6%	-6.3	14.4	50.0%
Arkansas	106	52.9%	55	43	78.2%	25	45.5%	49	14	28.6%	27	55.1%	-13.5	9.8	50.0%
LSU	112	76.8%	86	73	84.9%	41	47.7%	26	12	46.2%	15	57.7%	-14.7	6.0	50.0%
MtnWest	315	46.0%	145	107	73.8%	73	50.3%	163	37	22.7%	80	49.1%	-10.4	10.6	49.7%
Wisconsin	112	66.7%	74	59	79.7%	35	47.3%	37	12	32.4%	20	54.1%	-11.4	5.9	49.5%
W Virginia	107	67.3%	72	59	81.9%	36	50.0%	35	13	37.1%	17	48.6%	-13.5	8.6	49.5%
Minnesota	105	55.2%	58	42	72.4%	33	56.9%	47	9	19.1%	19	40.4%	-12.1	9.3	49.5%
N Carolina	104	35.0%	36	22	61.1%	14	38.9%	67	18	26.9%	37	55.2%	-7.8	11.4	49.5%
UAB	100	41.4%	41	24	58.5%	15	36.6%	58	15	25.9%	34	58.6%	-9.0	12.4	49.5%
Arizona	100	29.3%	29	18	62.1%	12	41.4%	70	18	25.7%	37	52.9%	-11.1	11.4	49.5%
S Miss	108	66.7%	72	54	75.0%	38	52.8%	36	8	22.2%	15	41.7%	-9.6	8.0	49.1%
Mississippi	103	50.0%	51	35	68.6%	19	37.3%	51	13	25.5%	31	60.8%	-9.7	11.3	49.0%
Iowa St	102	32.0%	32	25	78.1%	19	59.4%	68	14	20.6%	30	44.1%	-9.3	12.3	49.0%
Vanderbilt	98	25.5%	25	12	48.0%	8	32.0%	73	13	17.8%	40	54.8%	-9.2	13.0	49.0%
Virginia	109	45.8%	49	37	75.5%	22	44.9%	58	21	36.2%	30	51.7%	-10.7	9.1	48.6%
BYU	109	67.3%	72	57	79.2%	35	48.6%	35	10	28.6%	17	48.6%	-11.4	8.6	48.6%
Pittsburgh	105	56.3%	58	42	72.4%	26	44.8%	45	16	35.6%	24	53.3%	-10.5	9.2	48.5%
MAC	377	18.3%	69	51	73.9%	36	52.2%	304	45	14.8%	144	47.4%	-10.2	16.5	48.3%
Nebraska	110	73.1%	79	64	81.0%	40	50.6%	29	6	20.7%	12	41.4%	-16.3	9.2	48.1%
Notre Dame	110	55.6%	60	47	78.3%	30	50.0%	48	15	31.3%	22	45.8%	-11.2	8.8	48.1%
Wash St	104	47.1%	49	36	73.5%	22	44.9%	55	16	29.1%	28	50.9%	-10.4	12.2	48.1%
Florida Atl	48	33.3%	16	13	81.3%	10	62.5%	32	8	25.0%	13	40.6%	-6.6	14.9	47.9%
ACC	359	60.7%	218	172	78.9%	95	43.6%	135	41	30.4%	74	54.8%	-13.6	9.2	47.9%
Florida St	113	82.3%	93	68	73.1%	44	47.3%	20	7	35.0%	10	50.0%	-15.6	7.5	47.8%
Tennessee	114	69.9%	79	64	81.0%	36	45.6%	34	12	35.3%	18	52.9%	-13.2	5.9	47.8%
Georgia Tech	109	59.8%	64	44	68.8%	26	40.6%	43	19	44.2%	25	58.1%	-10.9	7.7	47.7%
Arizona St	107	57.0%	61	47	77.0%	35	57.4%	46	10	21.7%	16	34.8%	-11.0	7.9	47.7%
N Texas	104	31.1%	32	24	75.0%	19	59.4%	71	12	16.9%	30	42.3%	-8.2	16.6	47.6%
Purdue	108	67.0%	71	52	73.2%	34	47.9%	35	5	14.3%	16	45.7%	-11.2	7.2	47.2%
Colorado St	105	52.9%	54	34	63.0%	22	40.7%	48	16	33.3%	26	54.2%	-8.4	8.7	47.1%
Ohio	99	38.8%	38	25	65.8%	19	50.0%	60	10	16.7%	27	45.0%	-7.3	13.1	46.9%
San Diego St	99	21.4%	21	11	52.4%	10	47.6%	77	17	22.1%	36	46.8%	-6.7	12.0	46.9%
Arkansas St	97	30.2%	29	20	69.0%	11	37.9%	67	14	20.9%	34	50.7%	-6.9	14.7	46.9%
Colorado	111	49.5%	55	38	69.1%	27	49.1%	56	16	28.6%	25	44.6%	-8.7	11.0	46.8%
LA-Lafayette	94	31.5%	29	18	62.1%	12	41.4%	63	11	17.5%	31	49.2%	-5.8	16.3	46.7%
Tulsa	109	48.6%	52	38	73.1%	26	50.0%	55	12	21.8%	24	43.6%	-10.3	13.3	46.7%
Akron	103	40.8%	42	27	64.3%	17	40.5%	61	18	29.5%	31	50.8%	-9.5	11.5	46.6%
Big10	388	72.4%	281	220	78.3%	127	45.2%	102	29	28.4%	51	50.0%	-15.1	7.5	46.5%
Duke	99	08.1%	8	3	37.5%	2	25.0%	91	7	07.7%	44	48.4%	-7.3	17.3	46.5%
WAC	314	25.8%	81	63	77.8%	36	44.4%	227	39	17.2%	107	47.1%	-10.9	16.5	46.4%
Miami (FL)	108	82.4%	89	70	78.7%	38	42.7%	19	9	47.4%	12	63.2%	-17.4	6.8	46.3%
UCF	100	41.0%	41	28	68.3%	17	41.5%	59	13	22.0%	29	49.2%	-11.0	10.6	46.0%
W Michigan	99	45.9%	45	33	73.3%	22	48.9%	53	12	22.6%	23	43.4%	-10.6	12.5	45.9%
Michigan	111	79.8%	87	66	75.9%	38	43.7%	22	9	40.9%	12	54.5%	-12.5	6.1	45.9%
SunBelt	280	10.7%	30	17	56.7%	14	46.7%	249	29	11.6%	113	45.4%	-7.1	21.4	45.5%
Florida Intl	45	18.2%	8	4	50.0%	4	50.0%	36	5	13.9%	16	44.4%	-4.3	17.5	45.5%
Utah St	98	18.6%	18	11	61.1%	9	50.0%	79	13	16.5%	34	43.0%	-5.5	17.2	44.3%
Clemson	106	66.3%	69	48	69.6%	27	39.1%	35	14	40.0%	19	54.3%	-12.9	6.6	44.2%
Baylor	95	15.8%	15	14	93.3%	12	80.0%	80	7	08.8%	30	37.5%	-5.3	21.0	44.2%
E Michigan	95	12.6%	12	8	66.7%	6	50.0%	83	13	15.7%	36	43.4%	-6.1	15.7	44.2%
Memphis	101	46.0%	46	28	60.9%	18	39.1%	54	14	25.9%	26	48.1%	-8.1	8.2	44.0%
Tulane	100	24.5%	24	15	62.5%	11	45.8%	74	16	21.6%	32	43.2%	-8.4	12.6	43.9%
Kent	95	26.6%	25	11	44.0%	7	28.0%	69	15	21.7%	34	49.3%	-7.6	13.4	43.6%
CUSA	372	34.1%	127	88	69.3%	53	41.7%	240	41	17.1%	107	44.6%	-10.1	13.9	43.6%
Illinois	101	41.6%	42	28	66.7%	18	42.9%	59	9	15.3%	26	44.1%	-9.9	11.4	43.6%
SMU	103	22.8%	23	13	56.5%	11	47.8%	78	11	14.1%	33	42.3%	-6.2	14.4	43.6%
UTEP	101	34.7%	35	23	65.7%	14	40.0%	66	15	22.7%	30	45.5%	-9.7	13.3	43.6%
Michigan St	109	54.6%	59	39	66.1%	23	39.0%	49	15	30.6%	24	49.0%	-11.8	7.3	43.5%
Wyoming	100	26.3%	26	16	61.5%	9	34.6%	73	14	19.2%	34	46.6%	-8.0	11.6	43.4%
LA Tech	104	40.0%	40	33	82.5%	19	47.5%	60	10	16.7%	24	40.0%	-9.5	16.4	43.0%
Texas A&M	105	51.4%	54	42	77.8%	26	48.1%	51	11	21.6%	19	37.3%	-13.3	10.2	42.9%
Fresno St	113	62.5%	70	53	75.7%	25	35.7%	42	15	35.7%	23	54.8%	-15.0	9.8	42.9%
Alabama	111	66.7%	74	55	74.3%	29	39.2%	37	8	21.6%	18	48.6%	-12.4	6.0	42.3%
Houston	106	47.1%	48	34	70.8%	20	41.7%	54	11	20.4%	23	42.6%	-9.7	12.9	42.2%
UNLV	105	35.3%	36	19	52.8%	11	30.6%	66	13	19.7%	32	48.5%	-7.8	11.1	42.2%
Army	100	13.0%	13	7	53.8%	5	38.5%	87	10	11.5%	37	42.5%	-5.5	15.0	42.0%
Mississippi St	100	29.3%	29	18	62.1%	12	41.4%	70	14	20.0%	29	41.4%	-8.2	12.1	41.4%
Marshall	101	52.0%	52	40	76.9%	20	38.5%	48	11	22.9%	21	43.8%	-13.0	11.2	41.0%
Idaho	96	17.0%	16	7	43.8%	4	25.0%	78	12	15.4%	34	43.6%	-6.4	16.8	40.4%
New Mex St	99	30.3%	30	18	60.0%	9	30.0%	69	8	11.6%	30	43.5%	-9.0	14.3	39.4%
Washington	108	39.3%	42	26	61.9%	10	23.8%	65	18	27.7%	29	44.6%	-11.5	11.9	36.4%
Indiana	99	23.5%	23	15	65.2%	11	47.8%	75	14	18.7%	23	30.7%	-6.4	12.4	34.7%
W Kentucky	10	10.0%	1	0	0.0%	0	0.0%	9	0	0.0%	3	33.3%	-17.5	15.8	30.0%