Ted Bunn’s Blog

Last week, Christopher Beam published an article in Slate called The case for getting rid of tenure.  Tenure at US universities is a pretty strange system.  The rest of the workforce gets regular performance evaluations, which if unsatisfactory can lead to the worker being fired.  For college professors, there is in effect just one such performance evaluation.  Since it happens just once, the stakes are extremely high when it does come.

I think there’s a sensible case to be made against the tenure system, but at least some of Beam’s points are frankly kind of silly, starting with his first substantive argument:

As tuition climbs and universities struggle to pay their bills, tenure is starting to look unaffordable. Keeping a professor around indefinitely€”tenure means they can’t be forced to retire€”simply costs a lot … University debt jumped 54 percent last year, with an average debt of $168 million. If the average university tenured about 15 fewer professors, they’d be in the black.

In short, if colleges paid fewer salaries, they’d have more money.  That’s certainly true, but of course it’s not all by itself an argument.  Those tenured folks teach classes, conduct research, and generally do the things that professors are supposed to do.  The above is only an argument against tenure if tenured people do this job, on average, worse than the people you could hire for the same amount of money in an alternative, tenure-free system.  Maybe that’s true, but it’s certainly not obvious. In particular, tenure is a non-monetary job benefit.  If you get rid of it, you’re going to have to offer other incentives, probably higher salaries, to compete for qualified workers.

Next:

Tenure committees claim to weigh publishing and teaching equally, but in practice publishing counts most.

There are two points in response to this: First, it’s all too true at some places but not at others.  I actually chose to look for jobs at small undergraduate colleges precisely because they value teaching as well as research.  In order to get tenure, I was evaluated on both, and both were regarded as comparably important.

Second, even to the extent that this is a problem, it’s not directly related to the tenure system.  Whether tenure exists  or not, there’ll still be some system by which faculty are evaluated and rewarded.  If that system doesn’t value teaching, then faculty will not have an incentive to put effort into teaching.  That’s true whether the reward system is tenure, or renewal of fixed-term contracts (one of the main alternatives to tenure people talk about), or something else.

After a while, Beam gets to what most people regard as the main point of tenure: the academic freedom argument.

Once a professor gains tenure, the thinking goes, he or she can say anything without fear of being fired. Academia thrives on the circulation of dangerous ideas. The problem is, for every tenured professor who’s liberated at age 40 to speak his mind, there are dozens of junior professors terrified to say anything the least bit controversial, lest they lose their one shot at job security for life. Academia relies on young scholars to shake things up. Yet tenure incentivizes them not to. Instead, it rewards students who follow in the footsteps of the elders whose favor they will require when the day of judgment arrives.

I’m not sure what I think of this.  The meme that academics need to be free to express heretical new ideas is much more resonant, I think, in the humanities than in the natural sciences.  In my own field, I don’t see a big problem with people being scared to publish or speak about their work because it’s radically different from what the old folks are doing.  But maybe it is a problem in other fields.

Here, too, it’s not clear that tenure is the problem, though.  Whatever system you have, young folks are going to be evaluated by old folks.  If the old folks really are hostile to the radical innovations of the young folks, then those innovations are going to be disincentivized by whatever system of rewards is set up.

Here’s another instance of the same error:

Tenure can also discourage interdisciplinary studies, since professors are rewarded for plumbing deep into an established subject area rather than connecting two different ones.

Once again, this is a (possibly valid) critique of what universities value, but not of the specific system they use to reward the things they value.  You can imagine systems with tenure that reward interdisciplinarity, and systems without tenure that don’t.

He does make a couple of points that I think are valid in principle:

Just as tenure creates economic inflexibility, it also creates intellectual inflexibility. By hiring someone for life, a school gambles that his or her ideas are going to be just as relevant in 35 years.

…

Critics say that tenure hurts students by making professors lazy … If you can’t be fired, what’s to stop you from refusing to teach an extra course?

The second one, in particular, is the one that sounds the most persuasive to a lot of people: “Those lazy tenured professors, they never do any work!”  There certainly are people in that category (no, I won’t name names), but in my experience they’re actually not all that common.  For one thing, universities usually have a variety of ways (salary increases and other perks, etc.) to incentivize people to do good work.  For another thing, most academics are primarily motivated by some combination of a genuine love of their work and a desire for respect from their peers, both of which keep them working after tenure.

Although I think Beam’s article is largely silly, I actually do think that the current system would benefit from a significant reworking, mostly to make it more flexible.  At the moment, the system for a junior faculty member involves a rigidly set up “clock” leading to tenure at a specific time, usually at an age in the late 30s.  In a world with many two-career couples trying to start families, the rigidity of this system is a big problem (more for women than for men, but it’s not great for either sex).

At the end of his article, Beam actually recommends a system with tenure but with more flexibility. I think he’s right about that, even though I don’t think that it would have any effect on most of the “problems” he discusses in the rest of the article.

After reading the abstract of my most recent paper, Raymond commented

I'm amused by the writing pattern characteristic of abstracts. They always go

"Statement of something everybody knows. Statement of something nobody knows. I found out the thing nobody knows."

The part that amuses me is the "Statement of something everybody knows." Why state something everybody knows?

True.  The abstract is a highly stylized form.  In general, the conventions are implicitly assumed, but the journal Astronomy and Astrophysics even encourages authors to write “structured abstracts” making some of them explicit.

With abstracts, as with haiku or sonnets, the trick is to say something original and striking within the severe constraints of the form.  Of course, most abstracts, not excepting my own, fail to do this — as, probably, do most haiku and sonnets.  There’s no getting around Sturgeon’s Law.

Max Tegmark published a paper with the abstract in rhymed couplets.  I believe it was part of a bet.

Apparently the Kepler Space Telescope has discovered a lot of candidate planets orbiting other stars, including many small “Earth-like” ones.  Kepler scientist Dimitar Sasselov showed this slide at a TED talk:

That’s a few hundred planets discovered, with over 100 of them “Earth-like,” meaning at most twice Earth’s radius.

The official data release hasn’t happened yet — in fact, the Kepler team has been asking for an extension of the proprietary period before the data are released publicly — so maybe Sasselov wasn’t supposed to reveal this information publicly yet.  Certainly this is an odd way for this information to come out.

At the moment, we don’t have all the details.  I think the hard part in this whole business is removing all the possible ways to get false positives. Kepler searches for variations in the brightness of stars due to planets transiting (passing between the star and us).  There are various non-planet reasons such brightness dips can occur, and it takes a lot of effort to rule out these other possibilities.  That’s the reason the researchers want more time before going public.  So I don’t think it’s clear yet how certain they are that these planet candidates are really planets, but presumably Sasselov wouldn’t have shown this in his talk if they didn’t have good reason to think that lots of them are.

My impression is that these results are pretty consistent with what people expected.  The original discoveries of extrasolar planets mostly found very large (Jupiter-like) ones, but that’s just because the method they used to search was only sensitive to large planets.  Once a mission like Kepler came along, with the ability to detect small planets, I think people expected to see lots of small planets.  But of course, expecting isn’t the same thing as knowing!

I’m behind on my TV-watching these days, so I’m just getting around to watching Michio Kaku’s appearance on the Colbert Report a few weeks ago.  He says things that are exaggerated to the point of being clearly false:

1. When asked about teleportation, he says that “we’re already teleporting atoms.”  This is a reference to the technique known as “quantum teleportation,” which is really cool, but is just plain not teleportation in the sense Colbert means or in the sense that viewers will think he means.  The fact is that we can’t teleport anything, in anything like the usual understanding of that word, and nothing on our current research horizon suggests we’re anywhere near being able to.
2. Later, Kaku says, “Within the coming decade we will have something resembling a Harry Potter invisibility cloak.”  This is, again, simply not true.  Once again, the technique he’s referring to is pretty cool, but it’s absurd to suggest it’ll lead to anything remotely like “practical” invisibility ever, let alone in a decade.  If you stay perfectly still, are spherical, and are illuminated only with monochromatic polarized radio waves, then this technique can make you invisible.  I wouldn’t count on this to keep you from getting detention from Professor Snape.

In both cases, Kaku is not the original offender: both the quantum teleportation community and the “invisibility” researchers started the practice of overselling their goods.  But Kaku knows better, and he shouldn’t play this game. People already think that we scientists exaggerate our level of knowledge. Every time a well-known scientist does this, it lowers the credibility of all scientists.

I want to make a few followup points regarding yesterday’s post about the gender gap in the sciences.

Just to recap, the “Larry Summers hypothesis” is the idea that differences in intrinsic intellectual ability can explain the underrepresentation of women in academic science.  More specifically,  the proposed explanation is that, even if there’s no difference in average ability, men tend to have intellectual ability (as measured by scores on various tests) that scatters more widely than women.  That means that men populate the very extreme highs and lows of the distribution much more than women.  If being a successful scientist requires being in the extreme high end of this distribution, then that might explain the gender gap.

I don’t think this is likely to be a significant part of the explanation, for reasons I tried to explain.  The biggest one is that I don’t think that success in a scientific career is sufficiently strongly correlated with intelligence (where the “intelligence” is defined to mean “the thing that the tests in question measure”).  To be more specific, I certainly don’t think that it’s strongly correlated with presence in the high-end tail of the intelligence distribution, which is where the gender differences supposedly lie.

If we were just trying to explain the preponderance of men among Nobel Prize winners, maybe a case could be made for this effect (although even then I’m not sure).  But in fact the gender gap shows up much earlier and grows at each step.  (The “leaky pipe” is the usual metaphor here.)  More men than women major in physics; the ratio skews further at the Ph.D. level, still further at the level of faculty jobs, and even further among tenured faculty.  If you think that all of this is because of effects in the top 1% tail of the intelligence distribution, I’m afraid you’re making  a flattering overestimate of the physics community’s intelligence.  We’re tolerably bright, but not that bright.

But there are a couple of things I want to make clear:

1. People sometimes use your attitude about the Summers hypothesis as a proxy for your attitude about all sorts of other things: if you disbelieve the Summers hypothesis, you must believe in the mind as a blank slate, with no room for intrinsic biological differences between the sexes.  Conversely, if you believe in the Summers hypothesis, (according to some) you must be a sexist.  Those attitudes are ridiculous.  In particular, although I think the Summers hypothesis is probably wrong, I think that that intrinsic cognitive differences in the sexes are quite likely to be real and may explain all sorts of other phenomena. I’m even generally sympathetic to the evolutionary psychology point of view, which is anathema to a lot of people who argue against the Summers hypothesis.

(Incidentally, if I may play armchair psychologist for a moment, it seems to me that the authors of that NOVA blog post, which got me started on this whole subject, are making this error: they saw Tierney as sympathetic to the Summers point of view and concluded that he must believe in the whole constellation of despised ideas that they associate with that point of view.  I can’t see any other reason they would have so egregiously misrepresented what he said.)

2. I don’t think that adherents of the Summers hypothesis are bad people, and I don’t think that the hypothesis should be ruled out of the bounds of polite discussion (as many people seem to).  It’s an a priori possible explanation of the observed data, which is either true or false.  It has the right to a hearing, and its probability of being correct can and should be judged on empirical grounds, like any other hypothesis.  Personally, I think it must be found wanting on those grounds.  But it should not be ruled out a priori because we don’t like its social or political implications.

3. It may seem to follow from point 2 that Larry Summers got a raw deal, but my sympathy for him is extremely limited.  If you’re a politician (and yes, a University president is a politician), then you should know better than to speak off the cuff about an extremely controversial topic about which you clearly have given very little thought.  He made a boneheaded move in raising the subject the way he did, and he got what was coming to him.  Moreover, as is often the case when politicians are brought down by gaffes, this one probably wouldn’t have brought him down if he didn’t have a history of alienating people.

NY Times columnist John Tierney wrote a pair of columns on the much-discussed question of why women are underrepresented in math and the physical sciences.  I didn’t see these columns until someone pointed out this response to them on the PBS Inside NOVA blog:

Why aren’t there more women in the upper echelons of science? It’s a question with many answers, but John Tierney at the New York Times is only interested in one: Maybe women just aren’t smart enough.

This is such an inaccurate description of Tierney’s position that the authors would seem either not to have read his columns or to be deliberately misrepresenting them.  Tierney:

So why are women still such a minority in math-oriented sciences? The most balanced answer I've seen comes from two psychologists at Cornell, Stephen J. Ceci and Wendy M. Williams €” who, by the way, are married and have a daughter with a graduate degree in engineering. After reviewing hundreds of studies in their new book, "The Mathematics of Sex" (Oxford), they conclude that discrimination is no longer an important factor in keeping out women.

They find consistent evidence for biological differences in math aptitude, particularly in males' advantage in spatial ability and in their disproportionate presence at the extreme ends of the distribution curve on math tests (the topic of last week's column). But given all the progress made in math by girls, who now take more math and science classes than boys and get better grades, Dr. Ceci and Dr. Williams say that differences in aptitude are not the primary cause of the gender gap in academic science.

Instead, they point to different personal preferences and choices of men and women, including the much-analyzed difference in the reaction to parenthood. When researchers at Vanderbilt University tracked the aspirations and values of mathematically gifted people in their 20s and 30s, they found a gender gap that widened after children arrived, with fathers focusing more on personal careers and mothers focusing more on the community and the family.

Dr. Ceci and Dr. Williams urge universities to make it easier for a young scientist to start a family and still compete for tenure, but they don't expect such reforms to eliminate the gender gap in academic science. After all, the difficulty of balancing family and career is hardly unique to science, and academia already offers parents more flexible working arrangements than do other industries with smaller gender gaps.

The gap in science seems due mainly to another difference between the sexes: men are more interested in working with things, while women are more interested in working with people. There's ample evidence €” most recently in an analysis of surveys of more than 500,000 people €” that boys and men, on average, are more interested in inanimate objects and "inorganic" subjects like math and physics and engineering, while girls and women are more drawn to life sciences, social sciences and other "organic" careers that involve people and seem to have direct social usefulness.

Ceci and Williams (and hence Tierney) may be right or they may be wrong.  But to take this position and replace it with “women just aren’t smart enough” is shamefully dishonest.

For what it’s worth, my best guess is that the key factors explaining the gender gap are:

1. Girls being discouraged from doing math and science in school, starting from a very young age, by teachers, parents, and peers.
2. The family-unfriendly nature of the tenure-track job process.
3. Discrimination (almost 100% unconscious but no less harmful as a result) against women scientists by their peers.

Tierney does give more credence than I do to the Larry Summers hypothesis, that the gender gap is partly explained by the fact that more men than women lie at the extreme high-end tail in the distribution of math ability (as well as the other tail).  The NOVA blog post does a good job at laying out some of the reasons why this seems like an unlikely explanation.  Among many other reasons:

1. If this were the explanation, the effect would be uniform across cultures, but it isn’t.
2. In my experience, lying in the extreme tail in the distribution of scores on math tests is not all that highly correlated with being a successful scientist.  On the contrary, many of those extreme outliers lack the other skills needed for success in science.

So to the extent that Tierney is advocating this as the explanation for the gender gap, I think he’s probably wrong.  But it’s not fair to replace his actual position with an inflammatory and inaccurate straw man.

I like this Abstruse Goose comic about how scientists view the world:

The author’s commentary on this is “Poor bastards.”  Presumably he’s being ironic, but lots of people do feel this way.  But I’m with Feynman:

I have a friend who’s an artist, and he sometimes takes a view which I don’t agree with. He’ll hold up a flower and say, “Look how beautiful it is,” and I’ll agree. But then he’ll say, “I, as an artist, can see how beautiful a flower is. But you, as a scientist, take it all apart and it becomes dull.” I think he’s kind of nutty …. There are all kinds of interesting questions that come from a knowledge of science, which only adds to the excitement and mystery and awe of a flower. It only adds. I don’t understand how it subtracts.

(From What Do You Care What Other People Think?)

(Warning: I’m going way far away from any area where I could possibly claim expertise here.)

Nicholas Carr has a new book coming out, as well as an article in Wired,  about the possibility of cognitive changes arising from the huge changes in the way we consume information in the Internet age.  I think that’s an interesting subject, but the reviews and discussions of Carr’s writing have emphasized a trope that I think is very misleading and alarmist: the Internet, they say, is rewiring our brains.

It seems to me that the rewiring-our-brains language is intended to scare people, provoking a reaction similar to Miles Monroe‘s (“My brain?  But that’s my second favorite organ!”).  But it’s not clear that it really means anything.  Anything that changes your mental state (remembering something, forgetting something, learning a new skill, etc.) results in physical changes (“rewiring”) of your brain.

It’s interesting to ask whether the Internet is changing the ways we think, and if so, whether those changes are good or bad, and it’s certainly good for psychologists and neuroscientists to do experiments to try to figure out the mechanisms.  But let’s discuss the results dispassionately without scaremongering.

Steven Pinker said it well in his book The Blank Slate:

All this should be obvious, but nowadays any banality about learning can be dressed up in neurospeak and treated like a great revelation of science. “Talk therapy, a psychiatrist maintains, can alter the structure of the patient’s brain” [says a newspaper article].  I should hope so, or else the psychiatrist would be defrauding her clients … A special issue of the journal Educational Technology and Society was intended “to examine the position that learning takes place in the brain of the learner, and that pedagogies and technologies should be designed and evaluated on the basis of the effect they have on student brains.”  The guest editor (a biologist) did not say whether the alternative was that learning takes place in some other organ of the body like the pancreas or that it takes place in an immaterial soul.

And just recently,  there’s a nice blog post by Vaughan Bell explaining why you shouldn’t pay any attention when people tout a scientific result as having to do with neuroplasticity:

Neuroplasticity sounds very technical, but there is no accepted scientific definition for the term and, in its broad sense, it means nothing more than ‘something in the brain has changed’. As your brain is always changing the term is empty on its own.

He goes on to describe the wide range of things people can mean when they use this term.