Marginal Revolution

DNA for work and love

University of Akron demands DNA sample from faculty as condition of employment.

Dating sites use your DNA to find a perfect love match.

Hat tip to my true major histocompatibility complex match.

Whale size, an interior solution

How is this for a sentence to ponder?:

It’s a lot of water, the scientists have found: in one lunge, a fin whale can momentarily double its weight.

The full article is here and I'll peg it as one of the very best short pieces I've read this year.  Here is another stunning excerpt:

In order to make lunge-feeding work, you have to have a really big mouth to capture enough water in one gulp. But in order to have a big mouth, you need a big body. And in order to keep that big body running, you need to get a lot of food. And in the very act of getting that food–diving deep, lunging open-mouthed, and then pushing a school-bus-sized volume of water forwards–requires a lot of energy on its own.

Goldbogen and his colleagues wondered what sort of trade-off lunge-feeding whales faced between the costs and the benefits of eating like a parachute. To find out, they took advantage of measurements scientists made of hundreds of fin whales at whaling stations in the 1920s.

For the pointer I thank Carl Zimmer.  Herman Melville would have been proud.

The lessons of "Climategate"

I've had many readers emailing me, asking what I think of the "trove" of emails unearthed from climate change researchers.  I'll admit I haven't read through the rather embarrassing revelations, I've only read a few media summaries and excerpts.  I see a few lessons:

1. Do not criticize other people in emails or assume that your emails will remain confidential, especially if you are working on a politically controversial topic.  Ask a lawyer about this, if need be.  "Duh," they will say to you.

2. The Jacksonian mode of discourse, or mode of conduct for that matter, can do harm to your cause, especially if you are otherwise trying to claim the scientific high ground.

The substantive issues remains as they were.  In Bayesian terms, if it turns out that many leading scientists do not practice numbers one and two, I am surprised that you are surprised.  It's very often that the scientific consensus "sounds that way."

In other words, I don't think there's much here, although the episode should remind us of some common yet easily forgotten lessons.

I should add that this episode will seem very important to you, if you conceive of the matter in terms of the moral qualities of "us vs. them."

Addendum: Robin Hanson offers a similar opinion.  I wrote my post before reading his, yet we come to the same conclusions I think.

Jeremy Taylor quotes Richard Wrangham on the domestication of human beings

I think we have to start thinking about the idea that humans in the last 30, 40, or 50,000 years have been domesticating ourselves.  If we're following the bonobo or dog pattern, we're moving toward a form of ourselves with more and more juvenile behavior.  And the amazing thing once you start thinking in those terms is that you realize that we're still moving fast.  I think that current evidence is that we're in the middle of an evolutionary event in which tooth size is falling, jaw size is falling, brain size is falling, and it's quite reasonable to imagine that we're continuing to tame ourselves.  The way it's happening is the way it's probably happened since we became permanently settled in villages, 20 or 30,000 years ago, or before.

That's from Taylor's interesting new book Not a Chimp: The Hunt to Find the Genes that Make Us Human.  Taylor does stress that this hypothesis is speculation rather than established fact.

By the way, our skulls are becoming thinner, a process known as gracilization.

NASA FAQ 2012

NASA scientists are frequently being asked questions concerning 2012 and for this reason they have created a web page to answer these questions and reassure the public. e.g.

Q: Is there a planet or brown dwarf called Nibiru or Planet X or Eris that is approaching the Earth and threatening our planet with widespread destruction?

A: Nibiru and other stories about wayward planets are an Internet hoax. There is no factual basis for these claims. If Nibiru or Planet X were real and headed for an encounter with the Earth in 2012, astronomers would have been tracking it for at least the past decade, and it would be visible by now to the naked eye. Obviously, it does not exist. Eris is real, but it is a dwarf planet similar to Pluto that will remain in the outer solar system; the closest it can come to Earth is about 4 billion miles.

Sigh.... I too fear for our planet.

*You Are What You Choose*

Scott DeMarchi and James T. Hamilton have a new book out and the subtitle is The Habits of Mind That Really Determine How We Make Decisions.  I take this to be the key paragraph:

It's called fast food, but your decision-making process in ordering a chicken sandwich can be incredibly complex.  In the following section, we describe six core habits of mind that affect how you make decisions in all areas of your life.  We call these TRAITS: Time, Risk, Altruism, Information, meToo, and Stickiness.

Here is a review and explication of the book.

Does being sad, or complaining, make you smarter?

I have yet to read this study but I found the summary intriguing:

Bad moods can actually be good for you, with an Australian study finding that being sad makes people less gullible, improves their ability to judge others and also boosts memory.

The study, authored by psychology professor Joseph Forgas at the University of New South Wales, showed that people in a negative mood were more critical of, and paid more attention to, their surroundings than happier people, who were more likely to believe anything they were told.

"Whereas positive mood seems to promote creativity, flexibility, cooperation, and reliance on mental shortcuts, negative moods trigger more attentive, careful thinking paying greater attention to the external world," Forgas wrote.

"Our research suggests that sadness ... promotes information processing strategies best suited to dealing with more demanding situations."

Furthermore:

The study also found that sad people were better at stating their case through written arguments, which Forgas said showed that a "mildly negative mood may actually promote a more concrete, accommodative and ultimately more successful communication style."

I thank Claire Hill for the pointer.

So all you sad people can cheer up now.  Or not.

Interview with Denise Shull

She is using neurobiology to better understand traders' behavior and also to advise traders.  Here is one bit:

StockTickr: What single lesson did you learn along the way that has helped you the most in your trading?

Denise: Learn how to process your emotions in real time. so that the emotion is not “acted out” in trade entries or exits.

Here is a recent article on Denise Shull.  Unlike many contemporary researchers in her field, she still has a real attachment to Freud.  "Emotional intelligence" for traders is perhaps a good summary of her core message.  I wonder how many professions (bloggers? no) are lucrative enough to afford paid emotional intelligence consultants.

Via Daniel Hawes, here is a piece on how length-ratios of second and fourth digits predict success among high-frequency stock traders.  I can't say I'm convinced that "prenatal androgen exposure may affect a trader by sensitizing his subsequent trading performance to changes in circulating testosterone" but it's worth a read.

*From Eternity to Here*

The author is Sean Carroll and the subtitle is The Quest for the Ultimate Theory of Time.  This book-to-appear offers a very good summary of the paradoxes of time.  The new contribution (new to me, at least) is to offer an integrated discussion of the multiverse, the law of entropy, de Sitter space, and the foundations of the so-called "arrow of time."

Carroll argues that the invocation of baby universes clears up a lot of apparent puzzles:

The prospect of baby universes makes all the difference in the world to the question of the arrow of time.  Remember the basic dilemma: The most natural universe to live in is de Sitter space, empty space with a positive vacuum energy...most observers will find themselves alone in the universe, having arisen as random arrangements of molecules out of the surrounding high-entropy gas of particles...

Baby universes change this picture in a crucial way.  Now it's no longer true that the only thing that can happen is a thermal fluctuation away from equilibrium and then back again.  A baby universe is a kind of fluctuation, but it's one that never comes back -- it grows and cools off, but it doesn't rejoin the original spacetime.

What we've done is given the universe a way that it can increase its entropy without limit.

...[pages later]  In this scenario, the multiverse on ultra-large scales is symmetric about the middle moment, statistically, at least, the far future and the far past are indistinguishable...[yet] The moment of "lowest" entropy is not actually a moment of "low" entropy.  That middle moment was not finely tuned to some special very-low-entropy initial condition, as in typical bouncing models.  It was as high as we could get, for a single connected universe in the presence of a positive vacuum energy.  That's the trick: allowing entropy to continue to rise in both directions of time, even though it started out large to begin with.  There isn't any state we could possibly have chosen that would have prevented this kind of evolution from happening.  An arrow of time is inevitable.

Is it all true?  Beats me.  But if you read this book you will come away more hopeful about the prospects of a relatively simple "theory of everything."

Here is the author's home page; he teaches at Cal Tech.  Here is his personal page.  Best of all, here are his talks.  His Twitter feed is here.

How to flip a coin

Chris Blattman reports:

Using a high-speed camera that photographed people flipping coins, the three researchers determined that a coin is more likely to land facing the same side on which it started. If tails is facing up when the coin is perched on your thumb, it is more likely to land tails up.

How much more likely? At least 51 percent of the time, the researchers claim, and possibly as much as 55 percent to 60 percent — depending on the flipping motion of the individual.

The original research is here.