A good way to tell how well Vegas (and my simulator) did at predicting winners during the season is to compare blocks of games that had similar odds to each other. For example, I took the 100 games that had the highest favorite to win and calculated the average Vegas win expectancy of those games and compared across the board to my simulator and the actual results. I did this for all 100 blocks of games as well as blocks of 300 and blocks of 600. The smaller the block size the more noise you will have but the more interesting trends you will see. Below are tables of those three types of blocks of games.
100 Blocks of Games |   | 300 Blocks of Games |   | 600 Blocks of Games | |||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Blocks | Veg | Sim | Actual | Vegas | Sim | Actual | Vegas | Sim | Actual | ||||
1-100 | 0.6910 | 0.6723 | 0.6700 | 1-300 | 0.6615 | 0.6476 | 0.6267 | 1-600 | 0.6396 | 0.6301 | 0.6450 | ||
101-200 | 0.6549 | 0.6408 | 0.6100 | 301-600 | 0.6177 | 0.6126 | 0.6633 | 601-1200 | 0.5831 | 0.5762 | 0.5867 | ||
201-300 | 0.6387 | 0.6297 | 0.6000 | 601-900 | 0.5926 | 0.5858 | 0.5700 | 1201-1800 | 0.5486 | 0.5410 | 0.5517 | ||
301-400 | 0.6272 | 0.6217 | 0.6500 | 901-1200 | 0.5736 | 0.5666 | 0.6033 | 1801-2414 | 0.5171 | 0.5138 | 0.5220 | ||
401-500 | 0.6177 | 0.6059 | 0.6400 | 1201-1500 | 0.5569 | 0.5504 | 0.6033 | ||||||
501-600 | 0.6081 | 0.6101 | 0.7000 | 1501-1800 | 0.5404 | 0.5317 | 0.5000 | ||||||
601-700 | 0.5993 | 0.5943 | 0.6900 | 1801-2100 | 0.5251 | 0.5196 | 0.5033 | ||||||
701-800 | 0.5927 | 0.5821 | 0.5100 | 2101-2414 | 0.5095 | 0.5083 | 0.5399 | ||||||
801-900 | 0.5858 | 0.5810 | 0.5100 | ||||||||||
901-1000 | 0.5788 | 0.5784 | 0.5900 | ||||||||||
1000-1100 | 0.5734 | 0.5595 | 0.6100 | ||||||||||
1100-1200 | 0.5685 | 0.5620 | 0.6100 | ||||||||||
1201-1300 | 0.5629 | 0.5528 | 0.6500 | ||||||||||
1301-1400 | 0.5570 | 0.5519 | 0.6000 | ||||||||||
1401-1500 | 0.5507 | 0.5466 | 0.5600 | ||||||||||
1501-1600 | 0.5461 | 0.5360 | 0.5500 | ||||||||||
1601-1700 | 0.5402 | 0.5293 | 0.5400 | ||||||||||
1701-1800 | 0.5348 | 0.5298 | 0.4100 | ||||||||||
1801-1900 | 0.5303 | 0.5322 | 0.4600 | ||||||||||
1901-2000 | 0.5252 | 0.5230 | 0.5300 | ||||||||||
2001-2100 | 0.5199 | 0.5034 | 0.5200 | ||||||||||
2101-2200 | 0.5142 | 0.5111 | 0.5000 | ||||||||||
2201-2300 | 0.5098 | 0.5110 | 0.5400 | ||||||||||
2301-2414 | 0.5050 | 0.5035 | 0.5702 |