Tim DeRoche

Does the “hot hand” exist? New evidence says yes

A famous paper from the 1980’s  seemed to disprove the common idea that an athlete can develop a “hot hand”.  Gillovich, Vallone, and Tversky studied the 76ers and showed that – even if a player had made a bunch of shots in a row – the chance that he would make his next shot was still equivalent to his overall shooting percentage.

But now a Harvard team comes around to show that one of their key assumptions did not hold up.  Players actually take more difficult shots and face tougher defense when they’ve made a few shots.  They claim that there is indeed a small “hot hand” effect (1-2% increase in shooting percentage), but this effect is masked by increased shot difficulty and increased defense.

If getting hot makes you take worse shots, then the lesson for hoopsters is still the same: Play as if the hot-hand does not exist.

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“Why do men want to be smarter than their women.”

Althouse and Instapundit go back and forth on this, and Althouse takes down Reynolds’ “just-so” story:

“There’s no end to the stories one can generate to explain whatever science report happens to pop up in the press and inspire us to think of reasons why it’s true (if it’s true).”

I consider this as the son of a mother who is demonstrably smarter than my dad (on several different dimensions).  It – um – caused some difficult issues to pop up.

But intelligence is not a single, easy-to-define characteristic.  I wonder if men and women might prefer different kinds of smarts.  And I wonder why Althouse and Reynolds are focusing on what the men want.  Perhaps men want to be “smarter” than their mates because they know that a smarter woman will always be looking for the smarter male.  Maybe it’s the females’ preferences that matter most in the mate market.

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“We can’t pretend that things are more certain than they are.”

In a speech at the Scripps Oceanographic Institute, David Victor delivers a thoughtful critique of how climate science is discussed in the public sphere:

“First, we in the scientific community need to acknowledge that the science is softer than we like to portray. The science is not ‘in’ on climate change because we are dealing with a complex system whose full properties are, with current methods, unknowable. The science is ‘in’ on the first steps in the analysis—historical emissions, concentrations, and brute force radiative balance—but not for the steps that actually matter for policy. Those include impacts, ease of adaptation, mitigation of emissions and such—are surrounded by error and uncertainty. I can understand why a politician says the science is settled—as Barack Obama did…in the State of the Union Address, where he said the ‘debate is over’—because if your mission is to create a political momentum then it helps to brand the other side as a ‘Flat Earth Society’ (as he did last June). But in the scientific community we can’t pretend that things are more certain than they are.

Second, under pressure from denialists we in the scientific community have spent too much time talking about consensus. That approach leads us down a path that, at the end, is fundamentally unscientific and might even make us more vulnerable to attack, including attack from our own. The most interesting advances in climate science concern areas where there is no consensus but the consequences for humanity are grave, such as the possibility of extreme catastrophic impacts. We should talk less about consensus and more about the consequences of being wrong—about the lower probability (or low consensus) but high consequence outcomes. Across a large number of climate impacts the tails on the distributions seem to be getting longer, and for policy makers that should be a call for more action, not less. But people don’t really understand that, and we in the scientific community haven’t helped much because we are focused on the consensus-prone medians rather than the tails.”

HT Judith Curry and Dot Earth.

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Peer review “does not mean the science is good”

In Psychology Today, George Mason professor Todd Kashdan publishes a brutally honest critique of some of his published work:

“Just because research is published in a peer-reviewed journal by a reputable publisher does not mean the science is good.”

“I had to read through 40 articles to find one that suggested hands-free phones are not that hazardous to driving…but I did it, and now you too can tout scientific evidence that the hazards are overblown!”

“Often our research program starts off slow and I am not confident about each finding that comes out of my laboratory (or from other laboratories). I stay attuned to the main objective of why I am a psychologist…understand some of the mysteries of human behavior and in some small way, reduce the amount of suffering and increase the amount of well-being in the world. This cannot be done with a premature commitment to being right. This cannot be done by blindly accepting theories, research, and treatments that other people promote. But the key is to be skeptical, not cynical. Be curious, keep experimenting, keep learning, and most importantly, keep asking questions. And part of this storyline is to be naked, exposed, and vulnerable every once in awhile.”

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Theories about dark energy – mind-bending, highly creative, and occasionally nuts

Like all the rest of us, scientists are magical thinkers.  You can most easily see this when scientists struggle to explain an unexpected result, like the accelerating expansion of the universe.  In Slate, Matthew Francis runs through some of the made-up theories that haven’t yet been proven wrong or right.  These are barely distinguishable from superstition or science fiction.  And the vast majority – probably, in the long run, all of them – are likely to be proven wrong.  “Dark energy” itself is an invented concept whose sole purpose is to explain an unexpected observation.  As I understand it, there is no “energy” that scientists can identify, and the word “dark” is used solely to indicate that we don’t know what we’re talking about.

An unexpected observation cries out for explanation that will yield expected observations (predictions).  So scientist strive to make up stories that will lead to better predictions.  But there’s no reason to think that those stories actually correspond to what is out there in the universe.  There is also no reason at all to think that the realities of the natural world can be described accurately by human language.

But scientists have no other way to communicate about their findings than to use language, either co-opting words that already have some other meaning (e.g., “dark”) or creating words (e.g, “quark”).  I’m pretty sure that these words have no meaning outside their scientific context.

 

 

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