Some new research could upset some long-held notions about hot streaks

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For as long as I’ve been following sports — at least following it closely as an adult — there has been big tension between what people say about players in hot streaks and what the data shows. Athletes and most people who cover them have accepted hot streaks — whether they be by shooters in basketball or hitters in baseball — as something that actually influence or predict future events. The stats, however — most notably studies of basketball players in the 1980s which led to the recognition of “the hot hand fallacy” — has strongly suggested that recent past performance in small sample sizes do not predict future events.

One new study, however, presents evidence that hot streaks have predictive power. From James Wagner at the Washington Post:

Green and Zwiebel studied two million MLB at-bats from 2000 to 2011. They neutralized for the abilities of the hitter and pitchers — such as lefty-on-lefty matchups and stadium sizes — and focused on 10 major statistical categories, such as batting averages, home run percentages and strikeout rates.

They found that a hitter’s past 25 at-bats were a significant predictor of his next at-bat. When a player is hot, they found his expected on-base percentage to be 25 to 30 points higher than it would if he were cold. Home run rates jumped 30 percent and strikeout rates dropped. For pitchers in hot streaks, future performance was improved, too.

They don’t reach any hard and fast conclusions here, though there are some which seem plausible. Mostly related, I believe, to a new understanding of what is and what is not “random,” as the hot hand fallacy is based on data related to random events. I’m certainly no statistician so I can’t judge either this or other studies in this vein on their merits with any degree of authority. Maybe this supersedes the last best statistical evidence on the matter. Maybe it’s flawed. I have no idea.

My personal takeaway, though, is that there is always something to learn about baseball. And that rather than try to understand it through opinions held based on personal beliefs, authority and predispositions, it’s better to understand it based on the data. Those who skew old school have always been a bit loathe to do this. Now, however, a favorite concept of the statistically-oriented is being questioned. I’ll be curious to see (a) if this new study holds up to scrutiny; and (b) if it does, how the stats folks take to having some long-held beliefs of their own challenged.

Rays acquire Sergio Romo from Dodgers

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The Rays acquired right-handed reliever Sergio Romo from the Dodgers, the teams announced Saturday night. Tampa Bay manager Kevin Cash hinted that the team was in on Romo during the offseason, but couldn’t quite make a deal happen at the time. The righty reliever was designated for assignment by the Dodgers on Thursday and will net the club cash considerations or a player to be named later.

Romo, 34, struggled to find his footing in his first season with the Dodgers. He left a closing role in San Francisco to play set-up man to established closer Kenley Jansen, and saw mixed results on the mound with a 6.12 ERA, 4.3 BB/9 and 11.2 SO/9 through his first 25 innings of 2017. It’s a far cry from the sub-3.00 ERA he maintained in 2015 and 2016, but the Rays don’t seem to have ruled out a second-half surge just yet.

The veteran right-hander is expected to step into a bullpen that already boasts a solid core of right-handed relievers, including Alex Colome, Brad Boxberger, Erasmo Ramirez, Chase Whitley and Tommy Hunter. According to FOX Sports’ Ken Rosenthal, the Rays were intrigued by Romo’s extensive postseason experience, affordability and hefty strikeout rate, but will likely continue to hunt for additional bullpen depth in the weeks to come.

Colin Moran is carted off the field after taking a foul ball to the eye

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Astros’ third baseman Colin Moran was carted off the field on Saturday night after a foul ball caught him in the left eye. He was forced to leave in the sixth inning when a pitch from Orioles’ right-handed reliever Darren O'Day ricocheted off the handle of his bat and struck him in the face, causing considerable bleeding and bruising around his eye. The full extent of his injury has yet to be reported by the team.

Prior to the injury, Moran was 1-for-2 with a base hit in the third inning. He was relieved by pinch-hitter/third baseman Marwin Gonzalez, who polished off the end of the at-bat by catapulting a three-run homer onto Eutaw Street.

Evan Gattis and Carlos Beltran combined for another two runs in the ninth inning, bringing the Astros to a four-run lead as they look toward their 65th win of the season. They currently lead the Orioles 7-4 in the bottom of the ninth.