Simming 2018

Using Elo ratings, Baseball America simulated the Division I college baseball season 100 times to predict how everything would shake out.

Elo ratings are a way to measure the overall skill level of an individual or team in any sport that’s a zero-sum game. In other words, for every game winner there must be a game loser. The system was originally popularized as a way to rank chess players, but has now grown to reach dozens of different sports. Ratings are usually centered around the number 1500, with teams of greater skill being rated higher. These ratings can then be used to determine the win probability between any two teams.

In order to begin, every game of the season had to be collected from the NCAA’s schedule. Using Python, a programming language, each game’s home team, away team, and date were placed into an organized file. Games versus non-Division I opponents as well as games that were to be announced were filtered from the schedule.

Initial Elo ratings were drawn from WarrenNolan.com, which were based upon the end to the 2017 season. Ratings were then weighted towards 1500 because every team should theoretically regress to the mean – be more average – in a following season. This occurs mainly because of changes in skill-level – losing players to the draft, seniors moving on, transfers, a new freshman class – and luck.

With that in check, two more important values had to be found. The first is called a k-value – basically a multiplier applied to a team’s margin of victory to determine how much their Elo should change.

For example, let’s say UCLA beats Washington 10-7. UCLA’s Elo was 1550 and Washington’s was 1500. How many points should be awarded to UCLA? Adjust it by too much and the system interprets UCLA’s actual skill-level as improving too much; by too little and UCLA’s skill seems unaffected by the win. Since Elo ratings have a direct effect on win probability in this kind of simulation, changes by too large of a degree on either end can cause it to spiral out of control.

Testing which value would be best involves running the simulation on the 2017 season to see how accurate each k-value is. The same process is used to figure out just how important home-field advantage is. More on that can be found here. Now on to the simulation.

If you were to simulate the season just once, it’s possible that a team could be much stronger or weaker than originally predicted. After all, one season could go a number of different ways. However with each additional simulation, a team’s average is pushed towards their most probable outcome. That’s why running the simulation 100 times on all 7,943 games better captures the reality of the season.

In the table below, the average of all 100 simulations is provided, along with a measure of how much variability there is to each team. Higher variability implies that there’s a larger range of likely outcomes due to – among other things – close matchups.

All code can be found in this GitHub.

1	Oregon State	Pac-12	1779	43.9	12.1	0.783	High
2	LSU	SEC	1770	42.2	13.8	0.754	High
3	Florida	SEC	1767	41.5	14.5	0.742	High
4	Louisville	ACC	1731	40.6	15.4	0.725	Medium
5	TCU	Big 12	1723	38.9	15.1	0.721	Medium
6	Florida State	ACC	1705	37.1	18.9	0.663	High
7	Southern Miss	CUSA	1687	37.9	17.1	0.690	Medium
8	North Carolina	ACC	1684	35.7	19.3	0.649	Low
9	Stanford	Pac-12	1663	35.1	18.9	0.649	High
10	Wake Forest	ACC	1660	35.3	20.7	0.630	Low
11	Kentucky	SEC	1657	35.2	20.8	0.629	High
12	Virginia	ACC	1655	35.3	19.7	0.641	High
13	Arkansas	SEC	1654	34.6	21.4	0.618	High
14	Sam Houston State	Southland	1653	36.7	19.3	0.656	High
15	Long Beach State	Big West	1653	36.5	20.5	0.640	High
16	Texas Tech	Big 12	1649	34.0	22.0	0.608	High
17	South Alabama	Sun Belt	1643	35.6	20.4	0.636	Low
18	Coastal Carolina	Sun Belt	1642	36.4	19.6	0.651	High
19	Mississippi State	SEC	1638	32.9	23.1	0.587	Low
20	Houston	AAC	1636	33.9	22.1	0.605	High
21	Texas A&M	SEC	1635	33.4	22.6	0.596	Low
22	North Carolina State	ACC	1634	34.5	21.5	0.616	Low
23	Dallas Baptist	MVC	1625	33.1	21.0	0.612	Medium
24	BYU	WCC	1625	33.0	17.0	0.660	Low
25	Loyola-Marymount	WCC	1624	34.4	17.6	0.662	High
26	Rice	CUSA	1621	32.5	23.5	0.580	Low
27	Miami (FL)	ACC	1620	31.7	23.3	0.576	Low
28	Oral Roberts	Summit	1620	37.7	17.3	0.685	High
29	Cal State Fullerton	Big West	1619	32.6	22.4	0.592	High
30	Gonzaga	WCC	1618	32.2	19.8	0.619	Medium
31	South Carolina	SEC	1616	31.9	24.1	0.569	High
32	Missouri State	MVC	1615	32.4	20.6	0.611	Low
33	Texas	Big 12	1614	30.2	24.8	0.549	Medium
34	Clemson	ACC	1611	31.3	24.7	0.559	Medium
35	FGCU	Atlantic Sun	1610	35.4	19.6	0.644	Low
36	Southeastern Louisiana	Southland	1603	34.0	22.1	0.606	Medium
37	San Diego State	MWC	1602	35.3	19.7	0.641	Low
38	Vanderbilt	SEC	1602	30.3	25.7	0.541	High
39	Louisiana-Lafayette	Sun Belt	1602	31.5	24.5	0.562	Medium
40	Fresno State	MWC	1600	36.4	19.7	0.649	Medium
41	Arizona	Pac-12	1600	33.1	22.9	0.591	High
42	West Virginia	Big 12	1600	31.3	22.7	0.579	High
43	Indiana	Big Ten	1598	34.2	21.8	0.611	Low
44	Georgia Southern	Sun Belt	1595	33.0	23.0	0.589	High
45	Davidson	A10	1594	35.1	17.9	0.663	Medium
46	Jacksonville	Atlantic Sun	1593	34.0	22.0	0.607	Medium
47	Michigan	Big Ten	1593	32.0	20.0	0.615	High
48	UCF	AAC	1593	33.2	22.8	0.593	Medium
49	Yale	Ivy	1592	27.6	15.4	0.643	Low
50	Missouri	SEC	1591	31.6	24.4	0.564	Low
51	Iowa	Big Ten	1591	31.0	19.0	0.620	Low
52	Duke	ACC	1590	31.4	24.6	0.560	Low
53	Louisiana Tech	CUSA	1589	34.1	21.9	0.609	High
54	Charlotte	CUSA	1589	32.2	23.8	0.576	High
55	Central Arkansas	Southland	1588	35.5	20.5	0.634	Medium
56	Boston College	ACC	1588	30.1	23.9	0.557	Medium
57	Saint Mary’s College	WCC	1581	32.1	22.9	0.585	Low
58	Saint John’s	Big East	1581	33.7	21.3	0.613	Medium
59	UIC	Horizon	1581	34.6	16.4	0.679	High
60	Xavier	Big East	1580	31.1	22.9	0.576	Low
61	Minnesota	Big Ten	1579	31.7	22.3	0.588	Medium
62	FAU	CUSA	1578	30.3	24.7	0.551	Medium
63	East Carolina	AAC	1578	31.2	24.8	0.558	Medium
64	Oklahoma State	Big 12	1576	28.3	25.7	0.524	High
65	Tennessee Tech	OVC	1574	35.6	20.4	0.636	High
66	McNeese State	Southland	1573	31.0	24.0	0.563	Low
67	Ole Miss	SEC	1573	28.3	27.7	0.506	Medium
68	Georgia	SEC	1573	28.9	27.1	0.515	Low
69	Delaware	CAA	1573	34.5	19.6	0.638	High
70	Connecticut	AAC	1573	31.2	24.8	0.557	High
71	South Florida	AAC	1572	28.7	23.3	0.552	Medium
72	Bethune-Cookman	MEAC	1569	30.7	22.3	0.580	Medium
73	Binghamton	AEC	1569	31.7	19.3	0.622	Medium
74	Kansas	Big 12	1567	30.1	25.9	0.537	Low
75	Nebraska	Big Ten	1567	31.4	24.6	0.561	Low
76	California	Pac-12	1566	29.8	24.2	0.551	High
77	UNCG	SoCon	1566	33.4	20.6	0.619	High
78	San Diego	WCC	1565	29.2	24.8	0.540	Medium
79	Auburn	SEC	1565	27.9	28.1	0.498	Medium
80	Kansas State	Big 12	1565	29.9	26.1	0.534	Low
81	Baylor	Big 12	1565	25.9	26.1	0.497	High
82	UCLA	Pac-12	1562	29.5	26.5	0.526	Low
83	Maryland	Big Ten	1561	29.6	26.4	0.529	Low
84	Utah	Pac-12	1561	28.9	26.1	0.526	Low
85	Oklahoma	Big 12	1561	29.2	26.8	0.522	Medium
86	Old Dominion	CUSA	1558	30.5	25.5	0.545	Medium
87	Mercer	SoCon	1558	33.3	22.7	0.595	Medium
88	Arkansas State	Sun Belt	1557	30.8	25.2	0.550	Medium
89	Furman	SoCon	1557	31.3	22.7	0.580	High
90	Central Connecticut	NEC	1555	33.5	17.5	0.657	High
91	Cal Poly	Big West	1555	31.5	25.6	0.552	Medium
92	Kent State	MAC	1552	30.9	22.1	0.583	Low
93	UTA	Sun Belt	1551	28.9	25.1	0.536	High
94	Winthrop	Big South	1548	31.4	23.6	0.570	Medium
95	Michigan State	Big Ten	1548	30.0	24.0	0.556	High
96	Northwestern	Big Ten	1548	26.6	23.4	0.533	Low
97	New Mexico State	WAC	1546	32.3	22.7	0.588	High
98	Stetson	Atlantic Sun	1545	31.6	24.4	0.564	High
99	FIU	CUSA	1544	28.0	26.0	0.518	Low
100	VCU	A10	1544	31.1	24.9	0.556	High
101	Navy	Patriot	1544	34.3	16.7	0.672	High
102	Lamar	Southland	1543	29.9	25.1	0.544	High
103	Troy	Sun Belt	1542	29.1	26.9	0.520	Low
104	Wright State	Horizon	1540	30.7	24.3	0.559	Medium
105	Tulane	AAC	1539	26.3	29.7	0.469	Low
106	Georgia Tech	ACC	1538	26.4	29.6	0.471	Low
107	Belmont	OVC	1537	32.4	22.6	0.589	Medium
108	Seton Hall	Big East	1537	26.1	20.9	0.555	Low
109	UTSA	CUSA	1535	27.8	27.2	0.505	Medium
110	High Point	Big South	1534	30.1	22.9	0.567	Medium
111	Ohio	MAC	1532	31.8	20.2	0.611	Low
112	Illinois	Big Ten	1531	26.1	24.9	0.512	Medium
113	UNCW	CAA	1531	31.0	24.0	0.563	High
114	Grand Canyon	WAC	1531	29.8	25.2	0.542	Medium
115	Samford	SoCon	1530	31.2	24.8	0.558	Low
116	Presbyterian	Big South	1530	31.2	23.9	0.566	High
117	Tennessee	SEC	1529	25.9	30.1	0.462	Low
118	North Florida	Atlantic Sun	1528	27.3	24.7	0.524	Medium
119	Washington	Pac-12	1527	27.5	27.5	0.500	Medium
120	Creighton	Big East	1526	28.7	26.3	0.522	Medium
121	Houston Baptist	Southland	1526	27.2	26.8	0.505	Low
122	Liberty	Big South	1524	29.0	27.0	0.518	Low
123	Indiana State	MVC	1523	28.6	25.4	0.530	Low

124	William & Mary	CAA	1520	30.6	26.4	0.537	Medium
125	New Orleans	Southland	1520	27.5	28.5	0.491	Low
126	Saint Louis	A10	1519	31.0	23.0	0.574	Low
127	Cal State Bakersfield	WAC	1519	30.3	23.8	0.560	Medium
128	Rhode Island	A10	1519	28.0	26.0	0.519	Low
129	Nicholls State	Southland	1519	28.6	27.4	0.511	Medium
130	Sacramento State	WAC	1519	29.9	25.1	0.544	Medium
131	Stephen F. Austin	Southland	1518	28.6	25.4	0.530	High
132	Morehead State	OVC	1517	30.9	25.1	0.552	Low
133	Alabama State	SWAC	1517	29.7	18.3	0.619	High
134	Memphis	AAC	1516	26.8	29.2	0.478	High
135	Charleston	CAA	1516	30.2	25.8	0.539	Low
136	Cincinnati	AAC	1515	24.5	29.5	0.453	Low
137	Oregon	Pac-12	1513	25.0	30.0	0.454	Low
138	Fordham	A10	1513	30.5	21.5	0.587	High
139	Northeastern	CAA	1512	28.2	25.8	0.522	Low
140	UMBC	AEC	1512	29.7	24.3	0.550	Medium
141	Butler	Big East	1510	30.4	23.6	0.562	Low
142	Columbia	Ivy	1510	23.0	22.0	0.512	Low
143	Albany	AEC	1509	30.8	22.2	0.582	Low
144	Washington State	Pac-12	1507	23.9	30.2	0.442	Low
145	East Tennessee State	SoCon	1507	25.9	26.1	0.498	High
146	Austin Peay	OVC	1507	29.5	26.5	0.527	Low
147	Notre Dame	ACC	1506	21.4	30.6	0.411	Low
148	Marist	MAAC	1506	27.4	21.6	0.558	Medium
149	Radford	Big South	1505	29.0	28.0	0.508	High
150	Texas State	Sun Belt	1505	25.9	30.1	0.463	High
151	Marshall	CUSA	1505	26.3	27.7	0.486	Medium
152	Cal State Northridge	Big West	1502	27.1	30.9	0.468	Low
153	Canisius	MAAC	1502	28.2	22.8	0.552	Low
154	Middle Tennessee	CUSA	1502	25.6	30.4	0.458	Medium
155	Jackson State	SWAC	1501	27.5	18.5	0.598	Low
156	George Washington	A10	1501	29.7	26.3	0.529	High
157	New Mexico	MWC	1501	25.4	29.6	0.462	Medium
158	Bryant	NEC	1501	29.5	26.5	0.526	Medium
159	Jacksonville State	OVC	1500	27.1	26.9	0.501	Medium
160	Murray State	OVC	1500	28.1	24.9	0.530	High
161	Southeast Missouri	OVC	1499	28.0	26.0	0.518	High
162	Purdue	Big Ten	1498	25.5	29.5	0.464	High
163	Saint Joseph’s	A10	1498	27.8	22.2	0.556	Low
164	Kennesaw State	Atlantic Sun	1497	27.3	27.7	0.496	Low
165	Hawaii	Big West	1497	23.8	28.2	0.457	High
166	Western Carolina	SoCon	1496	26.1	29.9	0.466	Medium
167	UAB	CUSA	1493	24.9	30.1	0.453	Low
168	Stony Brook	AEC	1492	27.7	25.3	0.523	Low
169	Central Michigan	MAC	1489	26.0	27.0	0.491	High
170	Pittsburgh	ACC	1489	25.1	29.9	0.456	High
171	Ohio State	Big Ten	1488	26.1	30.9	0.457	Medium
172	Texas A&M-Corpus Christi	Southland	1487	24.4	28.6	0.460	Low
173	Arizona State	Pac-12	1487	24.2	30.8	0.439	High
174	Ball State	MAC	1485	28.9	27.1	0.516	Low
175	UC Irvine	Big West	1485	25.4	30.6	0.454	Medium
176	Alabama	SEC	1485	22.9	33.1	0.409	High
177	San Francisco	WCC	1483	25.0	30.0	0.455	High
178	North Dakota State	Summit	1481	24.4	21.6	0.531	High
179	Dartmouth	Ivy	1481	19.3	21.7	0.471	Medium
180	UC Davis	Big West	1480	24.5	30.5	0.445	Medium
181	Penn	Ivy	1480	22.0	20.0	0.525	High
182	Wichita State	AAC	1479	22.6	33.4	0.403	High
183	UC Santa Barbara	Big West	1478	25.6	30.4	0.458	Medium
184	Saint Bonaventure	A10	1477	27.0	24.0	0.530	Low
185	Air Force	MWC	1477	25.6	27.4	0.483	Medium
186	UC Riverside	Big West	1475	23.2	30.8	0.430	Medium
187	Northern Kentucky	Horizon	1474	26.1	26.9	0.493	High
188	Fairfield	MAAC	1474	26.1	26.9	0.492	Medium
189	Cornell	Ivy	1473	18.3	21.7	0.457	Low
190	Southern Illinois	MVC	1472	26.3	29.7	0.470	Low
191	Virginia Tech	ACC	1472	21.6	33.4	0.392	High
192	Florida A&M	MEAC	1472	26.2	25.8	0.504	Low
193	Eastern Michigan	MAC	1472	26.3	28.7	0.477	High
194	Little Rock	Sun Belt	1470	24.3	31.7	0.434	Low
195	Holy Cross	Patriot	1470	24.8	26.2	0.486	Low
196	North Carolina A&T	MEAC	1470	28.1	25.9	0.520	High
197	Lipscomb	Atlantic Sun	1469	24.7	30.3	0.450	High
198	Gardner-Webb	Big South	1469	25.5	29.5	0.464	Medium
199	Maine	AEC	1469	22.7	28.3	0.445	Low
200	Norfolk State	MEAC	1468	29.0	20.0	0.592	High
201	South Dakota State	Summit	1468	26.3	25.7	0.507	Medium
202	Wofford	SoCon	1466	25.3	30.7	0.451	High
203	Valparaiso	Horizon	1465	25.9	30.1	0.463	Medium
204	South Carolina Upstate	Atlantic Sun	1463	26.1	28.9	0.474	High
205	George Mason	A10	1462	27.9	28.1	0.498	Low
206	Nevada	MWC	1462	23.7	31.3	0.431	High
207	Eastern Illinois	OVC	1459	24.2	29.8	0.448	High
208	Rutgers	Big Ten	1459	23.4	30.6	0.434	Low
209	Northern Colorado	WAC	1457	21.6	23.4	0.480	Low
210	Campbell	Big South	1456	23.0	31.0	0.426	Medium
211	Penn State	Big Ten	1453	23.5	30.5	0.436	Low
212	Tennessee-Martin	OVC	1451	22.3	28.7	0.437	Medium
213	Elon	CAA	1451	25.4	30.6	0.454	Medium
214	Harvard	Ivy	1450	17.5	26.5	0.397	Low
215	UNC Asheville	Big South	1450	22.7	32.3	0.412	Low
216	Georgia State	Sun Belt	1449	22.1	33.9	0.394	High
217	Sacred Heart	NEC	1447	25.7	28.3	0.475	Medium
218	Western Michigan	MAC	1444	24.3	28.7	0.458	Low
219	Monmouth	MAAC	1441	25.7	28.3	0.476	Medium
220	Rider	MAAC	1441	27.2	26.8	0.503	Low
221	VMI	SoCon	1440	23.3	30.7	0.431	Low
222	North Carolina Central	MEAC	1439	25.7	27.3	0.484	Medium
223	Wagner	NEC	1439	26.3	29.7	0.470	Medium
224	Seattle	WAC	1438	25.9	27.1	0.488	Medium
225	Delaware State	MEAC	1437	26.9	20.1	0.572	High
226	Villanova	Big East	1435	25.5	27.5	0.482	Low
227	Iona	MAAC	1434	23.3	29.7	0.440	Low
228	Miami (OH)	MAC	1433	22.2	29.8	0.427	Medium
229	Georgetown	Big East	1433	23.1	32.9	0.413	Medium
230	Milwaukee	Horizon	1432	22.3	30.7	0.422	Low
231	Army	Patriot	1429	22.4	28.6	0.439	High
232	Niagara	MAAC	1429	23.1	26.9	0.463	Medium
233	Princeton	Ivy	1428	16.3	24.7	0.398	Low
234	USC	Pac-12	1427	18.6	36.4	0.338	Medium
235	Northwestern State	Southland	1427	22.1	33.9	0.394	Medium
236	Siena	MAAC	1426	23.6	31.4	0.429	High
237	Pepperdine	WCC	1426	19.6	32.4	0.376	High
238	Bucknell	Patriot	1425	20.8	26.2	0.443	High
239	Appalachian State	Sun Belt	1424	20.4	35.6	0.365	Low
240	Hartford	AEC	1424	19.4	33.6	0.366	Medium
241	Longwood	Big South	1423	23.3	32.7	0.416	Low
242	Texas Southern	SWAC	1423	22.9	25.1	0.477	Medium
243	San Jose State	MWC	1419	21.2	33.8	0.385	High
244	Bradley	MVC	1416	18.7	29.3	0.390	Low
245	Oakland	Horizon	1415	21.2	31.8	0.401	Low
246	Brown	Ivy	1415	13.7	23.3	0.371	Low
247	UMass Lowell	AEC	1414	20.3	34.7	0.369	Medium
248	Long Island	NEC	1414	26.0	30.0	0.465	Medium
249	James Madison	CAA	1412	22.4	33.6	0.400	Low
250	SIUE	OVC	1412	19.7	34.3	0.364	Low
251	Charleston Southern	Big South	1411	20.2	32.8	0.382	Medium
252	UMass	A10	1411	20.3	28.7	0.414	Medium
253	UNLV	MWC	1409	19.4	35.6	0.353	Low
254	Pacific	WCC	1403	19.2	32.8	0.370	High
255	UTRGV	WAC	1402	20.6	34.4	0.375	Medium
256	Utah Valley	WAC	1402	18.7	32.3	0.368	Medium
257	Lehigh	Patriot	1402	22.3	28.7	0.438	Medium
258	Evansville	MVC	1399	18.3	31.7	0.367	Low
259	Western Kentucky	CUSA	1399	18.0	37.0	0.327	High
260	Toledo	MAC	1398	19.5	33.6	0.367	Low
261	Illinois State	MVC	1397	16.5	32.5	0.337	High
262	Eastern Kentucky	OVC	1395	20.4	35.6	0.365	High
263	The Citadel	SoCon	1395	20.8	34.2	0.379	Low
264	Towson	CAA	1390	21.0	35.0	0.376	High
265	Dayton	A10	1389	20.7	36.3	0.364	High
266	Western Illinois	Summit	1383	20.3	30.7	0.399	Low
267	Northern Illinois	MAC	1382	18.8	34.2	0.354	High
268	Quinnipiac	MAAC	1381	19.6	33.4	0.370	Medium
269	Santa Clara	WCC	1381	16.8	36.2	0.317	High
270	Grambling	SWAC	1379	19.6	24.4	0.446	Medium
271	Bowling Green	MAC	1376	20.2	34.8	0.368	Medium
272	Richmond	A10	1376	20.6	35.4	0.368	High
273	Incarnate Word	Southland	1373	19.3	35.7	0.351	Medium
274	Hofstra	CAA	1369	15.8	30.2	0.344	Medium
275	Manhattan	MAAC	1365	19.3	35.7	0.350	High
276	Arkansas-Pine Bluff	SWAC	1361	18.7	28.3	0.397	Medium
277	Southern	SWAC	1357	16.9	28.1	0.375	High
278	Prairie View A&M	SWAC	1349	16.9	28.1	0.375	Medium
279	ULM	Sun Belt	1346	15.6	39.4	0.283	High
280	Portland	WCC	1340	14.6	38.4	0.275	High
281	Abilene Christian	Southland	1334	15.7	36.3	0.302	Medium
282	Fairleigh Dickinson	NEC	1325	18.0	34.0	0.347	High
283	Omaha	Summit	1324	16.1	37.9	0.298	Medium
284	Youngstown State	Horizon	1320	14.8	41.2	0.263	High
285	NJIT	Atlantic Sun	1310	13.8	33.2	0.294	High
286	Savannah State	MEAC	1307	11.9	30.2	0.282	Medium
287	Alcorn State	SWAC	1307	16.0	31.0	0.341	High
288	Lafayette	Patriot	1307	14.7	35.3	0.295	Medium
289	Maryland Eastern Shore	MEAC	1306	20.4	35.6	0.364	Medium
290	Coppin State	MEAC	1300	15.8	33.2	0.322	High
291	IPFW	Summit	1292	15.5	36.5	0.298	Low
292	La Salle	A10	1285	14.2	40.8	0.258	Medium
293	Chicago State	WAC	1281	14.6	41.4	0.261	Medium
294	Mount Saint Mary’s	NEC	1280	16.1	38.9	0.293	Medium
295	Mississippi Valley State	SWAC	1273	13.3	31.7	0.296	Low
296	Alabama A&M	SWAC	1272	14.0	34.0	0.291	High
297	Saint Peter’s	MAAC	1188	9.5	37.5	0.203	Low