Do the Astros need to give Miguel Tejada more days off?

by DyingQuail on Dec 22, 2008 8:10 PM CST Comment 4 comments

Earlier in the Hot Stove season, when everyone thought we might be trying to do things that would make our club better, there was a lot of discussion about whether or not Miguel Tejada needed an adequate platoon to ensure that he got more days off. I've always been a little skeptical of that prognostication, but I wanted to put some numbers to the idea and see what stuck.

You can find out...after the jump.

What follows is a rather unwieldy table, but one that looks at every single Tejada off-game (defined as a game in which Tejada did not start and played no more than one inning) and what his Triple Slash (AVG/OBP/SLG) was for the five games prior to the off-day, the three games prior to the off-day, the three games immediately following the off-day, and the five games immediately following the off-day. This method of analysis was possible for every off-day except for July 6th and July 9th because there were only two games separating the off-days. After the four groupings around off-days, I measured the average change in each of Tejada's Triple Slash categories in both the three day groupings and the five groupings. Finally, Tejada's season average for his Triple Slash stats are compared to his average performance after an off-day, both three and five days groupings.

While there is hopefully a lot to gleaned from all of this, keep in mind that there are only 7 data points for us to look at. Even worse, because of my definition of an off-day, July 6th doesn't count because Tejada played multiple innings of an extra inning affair against the Braves. Thus in the case of the five day groupings, only 5 data points exist and for three day groupings, 6.

Off Day	5 Days Before			3 Days Before (2 days for 7/9)
	AVG	OBP	SLG	AVG	OBP	SLG
May 15, 2008	0.400	0.435	0.400	0.385	0.357	0.385
Jun 6, 2008	0.053	0.142	0.105	0.091	0.231	0.182
Jul 6, 2008	0.143	0.143	0.143	0.167	0.167	0.167
Jul 9, 2008	N/A	N/A	N/A	0	0.111	0
Jul 23, 2008	0.286	0.286	0.333	0.077	0.077	0.077
Aug 8, 2008	0.286	0.286	0.304	0.286	0.286	0.357
Aug 19, 2008	0.200	0.238	0.250	0.250	0.308	0.333

Off Day	3 Days After (2 days for 7/6)			5 Days After
	AVG	OBP	SLG	AVG	OBP	SLG
May 15, 2008	0.357	0.357	0.500	0.330	0.364	0.524
Jun 6, 2008	0.182	0.308	0.455	0.300	0.364	0.75
Jul 6, 2008	0	0.111	0	N/A	N/A	N/A
Jul 9, 2008	0.231	0.231	0.231	N/A	N/A	N/A
Jul 23, 2008	0.500	0.462	0.500	0.526	0.524	0.684
Aug 8, 2008	0.308	0.308	0.615	0.381	0.409	0.619
Aug 19, 2008	0.462	0.462	0.538	0.318	0.318	0.409

	Average Change		Season Average		Triple Slash After 5 Days
5 Day AVG	0.126		AVG	0.283	AVG	0.371
5 Day OBP	0.118		OBP	0.315	OBP	0.396
5 Day SLG	0.319		SLG	0.415	SLG	0.597
					Triple Slash After 3 Days
3 Day AVG	0.159				AVG	0.340
3 Day OBP	0.126				OBP	0.355
3 Day SLG	0.251				SLG	0.473

None of this is really significant in the statistical meaning of the word, but one thing is for sure, Miguel Tejada was measurably better offensively after an off day—especially in terms of power production. It seems that there is a clear benefit to giving Tejada more rest days than the schedule allows for, perhaps an extra 3-4 a month (maybe more, maybe less depending on which month it is). In that context, it doesn't seem like whoever Tejada's back-up will be will see a significant amount of playing time. So, at least we don't have to be mad about not acquiring a back-up for Tejada now...right?

Thoughts? Comments? Reactions? Any speculation as to why his SLG improves so much more?

This would not have been possible, for me at least, without Baseball Reference's Game Logs. Thank you Baseball Reference.

0 recs | Comment 4 comments | Share

Story-email Email Printer Print

Comments

Good job getting that level of detail.

The results, though a small sample size, confirms my subjective impression that Tejada hit better every time he came back from a day off. I had the same impression about Biggio; in his later years, Bidge seemed to hit better when came back from off-days.

I can only take wild guesses as to why. As an old guy, myself, I look to my own personal experience. I like to play tennis. A lot. Ten years ago, I might play tennis 3 – 4 times a week. However, as I get older, sore joints in my shoulder and feet diminish my performance toward the end of matches.So now I play 1 or 2 times per week and that seems to help. Even though I always subscribed to the idea that practice makes you better, I now find that if I haven’t played in week or so, I feel refreshed and physically play more like I did when I was younger.

As an older player, I’m sure that Tejada has nagging physical issues which he doesn’t talk about publicly. Maybe a day off lets his body heal a bit and he feels better. Heck, maybe it is partly psychological.

by clack on Dec 22, 2008 9:58 PM CST reply actions 0 recs

I understand

Undeniably, he played better (even that better wasn’t all that great in a few instances) coming from the off day. For me, the question is how valid is this, or how much is influenced by chance and the myriad of other factors that could influence his post-off-day performance.

I was pleased that he really doesn’t need a ton of off-days if this pattern holds, which is a lot better than the dire warnings we were hearing earlier in the off-season.

Once I had finished the spread sheet, I realized that it might have made a lot more sense to see what he splits were after regular off-days in the schedule…then my eye’s glazed over thinking about all that data collection. I put that project in the “If the planets align” section of my to do list. If anyone wants to beat me to the punch…please do.

The Crawfishboxes
A good friend of mine used to say, "This is a very simple game. You throw the ball, you catch the ball, you hit the ball. Sometimes you win, sometimes you lose, sometimes it rains." Think about that for a while.

by DyingQuail on Dec 23, 2008 12:19 AM CST up reply actions 0 recs

given the sample size, you won't know...

if it is statistically significant, even if you do the additional analysis.

by clack on Dec 23, 2008 5:05 AM CST up reply actions 0 recs

Statistically Significant?

Not really….but am I willing to wait around for Tejada to gather 1000 AB just to see if this holds to three decimal places? Not really. There are some decisions that you’ve just gotta make based on observation/anecdote/small evidence, and I think giving Tejada regular rest is one of them.

Thanks for doing this! I know how tiresome it can be to go through game data to pull out that info.

by AstroAndy on Dec 23, 2008 9:31 AM CST reply actions 0 recs

Comments For This Post Are Closed

Search

FanPosts

Community blog posts and discussion.

Recommended FanPosts

Pitching Mechanics/Terms To Look/Listen For

by baggs 2 days ago

9 comments | 4 recs

Recent FanPosts

+ New FanPost All FanPosts >

NL Central Standings

	W	L	PCT	GB	STRK
St. Louis Viva El Birdos	91	71	.561	0	Lost 6
Chicago Bleed Cubbie Blue	83	78	.515	7.5	Lost 1
Milwaukee Brew Crew Ball	80	82	.493	11	Won 3
Cincinnati Red Reporter	78	84	.481	13	Won 2
Houston The Crawfish Boxes	74	88	.456	17	Lost 3
Pittsburgh Bucs Dugout	62	99	.385	28.5	Lost 2