Radio Silence

Not much activity here of late in terms of blog posts, but plenty of calibrating and testing going on behind the scenes for my baseball simulator. I have been back testing a few code changes both in and out of sample for the previous seasons. I am excited about the results I've been getting and I am really looking forward to the 2011 season getting started. I may have a few "just for fun" posts between now and the start of the season, when I begin posting the simulation results of actual games.

For now, I'd like to kick things off with a post documenting the win-loss records of all 30 teams from the August 1st until the end of the season, roughly the last 38 games for each team. I believe that over a 2 month period there are some interesting talent trends that begin to form. One of the most important calibrations for my simulator is determining the correct weighting of past performance in an attempt to best predict current true talent levels. You do not want to weight recent performance to heavy to the point that you are putting too much of an emphasis on good/bad luck. On the other hand, you do not want to give too much weight to past, or old performance to the point that you will miss out on a change in a players true talent level. A formula which strikes the best balance between the two is very challenging and requires a careful set of tests on an in and out of sample set of games. My measuring stick is always the ROI (return on investment) of bets against the Vegas money lines. While I am always looking for flaws in my methodology and ways to improve my results, I believe I have found a good balance between past and recent performance. Thus my interest in the records of each team over the last two months of the season. The table(s) below provide some interesting data, even though some teams have changed more than others this off season, it is interesting to be reminded of how each team finished off the last portion of the season.

2011 Standings (Aug 1st - Oct 3rd)
Team	Div	Wins	Losses	WPct
PHI	NLE	40	17	.702
MIN	ALC	36	22	.621
BAL	ALE	33	24	.579
CIN	NLC	33	24	.579
SF	NLW	32	25	.561
TB	ALE	32	27	.542
ATL	NLE	32	27	.542
HOU	NLC	32	27	.542
TOR	ALE	31	27	.534
BOS	ALE	30	28	.517
CHA	ALC	30	28	.517
MIL	NLC	29	28	.509
TEX	ALW	29	29	.500
CHN	NLC	29	29	.500
COL	NLW	29	29	.500
SD	NLW	30	30	.500
NYA	ALE	29	30	.492
OAK	ALW	29	30	.492
DET	ALC	28	30	.483
STL	NLC	28	30	.483
LAA	ALW	27	29	.482
FLA	NLE	27	30	.474
ARI	NLW	27	31	.466
CLE	ALC	26	32	.448
NYN	NLE	26	32	.448
LAN	NLW	26	32	.448
KC	ALC	23	35	.397
WAS	NLE	23	35	.397
SEA	ALW	22	35	.386
PIT	NLC	21	38	.356

Now how about a look at how the playoffs would have looked like using only the last two months of the season as final win-loss records. The National League ends up with the exact same four teams (PHI, CIN, SF, ATL) that actually ended up making the playoffs. In the American League, we end up with three of the four teams (MIN, TB, TEX) that actually made the playoffs. The one American League team, and the only one out of eight playoff teams in both leagues that did not make the playoffs was the Yankees, who were replaced with the Orioles who had tied the third best record of any team over the last two months of the season.

American League
Rays	vs Twins
Rangers	vs Orioles
National League
Giants	vs Phillies
Braves	vs Reds

So our one surprise team is the Orioles. What happened to their team? Did their players suddenly improve their true talent levels? Or did their luck just improve? It is a likely combination of the two. The important part is obviously being able to measure how much of it was luck and how much of it was an actual positive talent trend. The early 2011 simulations will likely show some favorable Oriole predictions. It will be interesting to see how a team like the Orioles does during the first month or two of the season in the tough AL East division.

Next up, I will begin to look at some head to head two team matchups as the rosters begin to shape up. Also I will have a 2011 "crazy prediction" post, where I make a crazy and "just for fun" prediction for each team, just as a break from the usual logic driven posts I make.

Slip Sliding Away

The Dodgers lead in the NL West is "Slip Sliding Away!".

NL West Standings
Team	W	L	GB	Pecota NL West Champ Chances
Dodgers	67	45	0	78.13%
Rockies	61	50	5.5	16.60%
Giants	61	50	5.5	5.25%
Diamondbacks	50	62	17	0.01%
Padres	47	66	20.5	0.00%

NL West is the Best

Remember all the pre-season talk about how bad the NL West would be in 2009? Well, we are well over a third of the way through the season and the NL West has the best winning percentage of any division in the National League. The NL West has the best team in all of baseball, followed by the current NL Wild-Card leader. Not too shabby if you ask me. Let's take a look at the breakdown of the standings in the NL West and how the two other divisions stack up.

NL West Standings
Team	W	L	Pct
Dodgers	42	22	.656
Giants	34	28	.548
Rockies	31	32	.492
Padres	28	34	.452
Diamondbacks	27	37	.422
NL West	162	153	.514
NL Central	188	185	.504
NL East	146	164	.471

So much for the "haters" excusing the Dodgers MLB best record on the division they play in. The NL West is more than holding it's own up to this point. Fans of the NL West will point to the pathetic 16-45 record of the Washington Nationals pulling down their division. While this is true, it is also inflating the records of the top four NL East teams. The NL Central is a solid division, but lacks the dominating team that the NL West has. I cut the NL Central teams some slack, because they have 5 other divisional foes to beat out every season, as opposed to the 4 that the other two NL West divisional teams must beat out. But in the end, I think the wild-card evens that out.