slow starts and run differential, part two

this writer has often found it instructive to revisit fruitful lines of thought with the blessing of greater data to see if new conclusions can be wrung from the rag. much continues to be made, as the cubs continue to struggle, of the positive run differential that the team is losing in spite of. the club has scored 112 and allowed just 91, but offers a 10-14 record.

how strange is this? what does it say about the club? does it say anything about matters going forward? and, if so, what?

updating this study of some two weeks ago, what follows is a listing of every major league team since 1973 to have posted, as of april 30, both a losing record and a positive run differential. there have been 76 such teams, not including the six newly minted this season. they are sorted by disparity -- maximal to minimal -- between their actual record and the record implied by runs scored and allowed, commonly called the pythagorean record.

		as of 4/30								after 4/30
year	team	w	l	win%	rs	ra	rd	pythag	a-t	w after	l after	win% after	win% final
2007	chc	10	14	0.417	112	91	10.3%	0.593	0.177
1998	min	11	16	0.407	137	116	8.3%	0.575	0.168	59	76	0.437	0.432
1975	nyy	9	10	0.474	99	72	15.8%	0.641	0.167	74	67	0.525	0.519
1986	pit	7	10	0.412	87	74	8.1%	0.573	0.161	57	88	0.393	0.395
1990	min	7	12	0.368	88	83	2.9%	0.527	0.158	67	76	0.469	0.457
1980	phi	6	9	0.400	75	67	5.6%	0.551	0.151	85	62	0.578	0.562
1984	mil	9	11	0.450	91	73	11.0%	0.599	0.149	58	83	0.411	0.416
1974	kcr	8	11	0.421	98	86	6.5%	0.559	0.138	69	74	0.483	0.475
1991	atl	8	10	0.444	75	63	8.7%	0.579	0.134	86	58	0.597	0.580
1977	laa	9	13	0.409	117	107	4.5%	0.541	0.131	65	75	0.464	0.457
2007	nyy	9	14	0.391	131	125	2.3%	0.521	0.130
1997	sdp	9	15	0.375	100	99	0.5%	0.505	0.130	67	71	0.486	0.469
1994	phi	9	14	0.391	117	112	2.2%	0.520	0.129	45	47	0.489	0.470
1985	phi	8	11	0.421	80	73	4.6%	0.542	0.121	67	76	0.469	0.463
1997	nym	12	14	0.462	116	97	8.9%	0.581	0.119	76	60	0.559	0.543
1982	lad	10	11	0.476	94	77	9.9%	0.590	0.114	78	63	0.553	0.543
1980	mil	7	8	0.467	80	67	8.8%	0.580	0.113	79	68	0.537	0.531
2005	hou	9	13	0.409	84	80	2.4%	0.522	0.113	80	60	0.571	0.549
1985	stl	8	11	0.421	84	78	3.7%	0.534	0.113	93	50	0.650	0.623
1978	cle	8	11	0.421	85	79	3.7%	0.533	0.112	61	79	0.436	0.434
1977	cin	9	10	0.474	99	82	9.4%	0.585	0.111	79	64	0.552	0.543
1976	bos	6	7	0.462	63	54	7.7%	0.570	0.108	77	72	0.517	0.512
1994	lad	11	12	0.478	129	107	9.3%	0.584	0.106	47	44	0.516	0.509
1985	mil	8	11	0.421	76	72	2.7%	0.525	0.104	63	79	0.444	0.441
2001	fla	10	14	0.417	119	114	2.1%	0.520	0.103	66	72	0.478	0.469
1987	det	9	12	0.429	91	85	3.4%	0.531	0.102	89	52	0.631	0.605
1973	nyy	9	10	0.474	85	72	8.3%	0.575	0.101	71	72	0.497	0.494
1983	det	8	9	0.471	89	76	7.9%	0.571	0.101	84	61	0.579	0.568
1977	nym	8	9	0.471	69	59	7.8%	0.571	0.100	56	89	0.386	0.395
2001	sdp	10	15	0.400	128	128	0.0%	0.500	0.100	69	68	0.504	0.488
2002	tex	10	15	0.400	120	120	0.0%	0.500	0.100	62	75	0.453	0.444
1982	cle	8	10	0.444	97	88	4.9%	0.544	0.100	70	74	0.486	0.481
1978	mil	9	11	0.450	117	105	5.4%	0.549	0.099	84	58	0.592	0.574
1990	sdp	9	10	0.474	90	77	7.8%	0.571	0.097	66	77	0.462	0.463
1999	laa	11	12	0.478	132	112	8.2%	0.574	0.096	59	80	0.424	0.432
1976	sdp	9	10	0.474	85	73	7.6%	0.569	0.095	64	79	0.448	0.451
1999	kcr	9	11	0.450	109	100	4.3%	0.539	0.089	55	86	0.390	0.398
1988	mil	9	11	0.450	82	76	3.8%	0.535	0.085	78	64	0.549	0.537
1989	lad	11	13	0.458	79	72	4.6%	0.542	0.084	66	70	0.485	0.481
2006	atl	10	14	0.417	115	115	0.0%	0.500	0.083	69	69	0.500	0.488
1979	stl	9	10	0.474	86	76	6.2%	0.556	0.082	77	66	0.538	0.531
1983	chw	8	10	0.444	91	86	2.8%	0.526	0.081	91	53	0.632	0.611
1989	min	10	12	0.455	108	100	3.8%	0.535	0.080	70	70	0.500	0.494
2005	mil	10	13	0.435	102	99	1.5%	0.514	0.079	71	68	0.511	0.500
1978	stl	9	12	0.429	90	89	0.6%	0.505	0.077	60	81	0.426	0.426
1979	chw	9	11	0.450	106	100	2.9%	0.526	0.076	64	76	0.457	0.456
1999	cin	9	12	0.429	97	96	0.5%	0.505	0.076	87	55	0.613	0.589
2006	lad	12	13	0.480	122	108	6.1%	0.555	0.075	76	61	0.555	0.543
1989	phi	11	12	0.478	113	101	5.6%	0.551	0.073	56	83	0.403	0.414
2000	oak	12	13	0.480	135	121	5.5%	0.550	0.070	79	57	0.581	0.565
1975	bal	7	9	0.438	66	65	0.8%	0.507	0.069	83	60	0.580	0.566
1979	det	7	9	0.438	80	79	0.6%	0.506	0.068	78	67	0.538	0.528
2007	phi	11	14	0.440	123	121	0.8%	0.507	0.067
2004	phi	10	11	0.476	88	80	4.8%	0.543	0.067	76	65	0.539	0.531
2006	ari	12	13	0.480	124	112	5.1%	0.546	0.066	64	73	0.467	0.469
2002	bal	12	14	0.462	121	114	3.0%	0.527	0.066	55	81	0.404	0.414
1994	sea	10	13	0.435	115	115	0.0%	0.500	0.065	39	50	0.438	0.438
2000	sdp	11	14	0.440	137	136	0.4%	0.503	0.063	65	72	0.474	0.469
2003	laa	13	14	0.481	140	127	4.9%	0.544	0.063	64	71	0.474	0.475
1998	sea	12	15	0.444	161	159	0.6%	0.506	0.061	64	70	0.478	0.472
1981	atl	9	10	0.474	68	63	3.8%	0.535	0.061	41	46	0.471	0.472
2002	hou	11	14	0.440	121	121	0.0%	0.500	0.060	73	64	0.533	0.519
1998	oak	12	14	0.462	136	130	2.3%	0.521	0.059	62	74	0.456	0.457
1983	sdp	10	12	0.455	107	104	1.4%	0.513	0.058	71	69	0.507	0.500
1989	bos	10	12	0.455	114	112	0.9%	0.508	0.054	73	67	0.521	0.512
1991	chc	10	11	0.476	87	82	3.0%	0.527	0.051	67	72	0.482	0.481
1985	atl	9	10	0.474	77	73	2.7%	0.524	0.051	57	86	0.399	0.407
1994	kcr	9	11	0.450	117	117	0.0%	0.500	0.050	55	40	0.579	0.557
2007	oak	12	13	0.480	95	89	3.3%	0.530	0.050
1996	chc	13	14	0.481	136	128	3.0%	0.528	0.046	63	72	0.467	0.469
2005	nym	11	13	0.458	110	109	0.5%	0.504	0.046	72	66	0.522	0.512
1974	cle	10	11	0.476	100	96	2.0%	0.519	0.042	67	74	0.475	0.475
2005	sdp	11	13	0.458	105	105	0.0%	0.500	0.042	71	67	0.514	0.506
1996	pit	12	14	0.462	131	131	0.0%	0.500	0.038	61	75	0.449	0.451
1987	kcr	9	10	0.474	84	82	1.2%	0.511	0.037	74	69	0.517	0.512
1986	tex	9	10	0.474	103	101	1.0%	0.509	0.035	78	65	0.545	0.537
1997	kcr	11	12	0.478	112	109	1.4%	0.512	0.034	56	82	0.406	0.416
1986	kcr	9	10	0.474	73	72	0.7%	0.506	0.033	67	76	0.469	0.469
1974	phi	10	11	0.476	89	88	0.6%	0.505	0.029	70	71	0.496	0.494
2007	fla	12	13	0.480	143	141	0.7%	0.506	0.026
1993	atl	12	13	0.480	83	82	0.6%	0.506	0.026	92	45	0.672	0.642
2007	cin	12	13	0.480	109	109	0.0%	0.500	0.020

from this, what can we learn?

the first and most obvious thing is the rarity of the 2007 cubs' current situation. in 35 seasons, this team shows the greatest early season disparity between actual and theoretical record. this must be seen as a consequence of one of the stranger splits you'll likely see, dear reader -- the cubs are both 0-6 in one-run games, and 6-1 in blowout games (that is, those decided by five or more runs). both of these trends figure to revert to the mean over time.

the second and less enchanting bit of information that can be gleaned is that, despite that rare and massive difference, the outlook for the cubs going forward is perhaps not nearly so positive as one might hope based on run differential to date. as one can see, of the next 15 clubs that so underperformed their pythagorean projection by the largest margin, only six have been able to reach .500 by year-end -- and further, just 3 of the worst 10. the average year-end winning percentage of these 15 is .487 with a deviation of .056. it would seem that a brisk pace of positive run differential through april 30 is hardly a guarantor of future success.

the data can be otherwise sorted to yield further unwelcome conclusions. this writer has noted that the largest barrier to success is now the simple fact of being 10-14. it is hard to make up four games against .500 for most clubs, particularly for one that is thought to be relatively mediocre.

indeed, when this sample is sorted by actual winning percentage through april 30, the cubs place 12th-worst of the 82 teams at .417 -- and of the worst 15 by that measure, just three have finished the year over .500. the average winning percentage of this lot is .483 with a deviation of .056. as it happens, the large majority of clubs in the entire sample who did finish at or over break-even in the end were no more than two games under .500 at this point.

there is also, however, some reason for hope.

the cubs pythagorean projection at this time is .593 -- implying a 96-win pace. that is the third-highest such figure in the lot, and the peer group is a somewhat happier one. of the top 15, fully 8 broke .500 even though only two continued to post run differential at such a high pace as they did in april. six of this sample even managed to break a .525 winning percentage (corresponding to 85 wins). though the mean winning percentage of these fifteen is .491, the standard deviation is .064 -- implying a probable range of .427 to .555.

how then to view the data? the hopeful may take away elements of the last point to the ignorance of the rest, but the balance must seem to indicate that the cubs have made in april a rather negative statement in regards to where they will be in september in spite of posting a losing record in one of the more encouraging ways imaginable. that further comports with other estimations of what has transpired in april -- with the team due to lose in mean reversion in pitching more severely than it stands to gain in offense, with improvement in one-run games likely to be offset by a higher loss rate in blowouts, it is hard to see how the promise of this early-season vacillation of run differential will be likely to materialize into a dramatically better ballclub.

given further that the club is now chasing a decent milwaukee club at a five-and-a-half game disadvantage, it seems here that what was indicated a week ago was probably no accident.