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April 27, 2012

This week's picks

Origins and Genetic Legacy of Neolithic Farmers and Hunter-Gatherers in Europe "DNA from ~5000-year-old remains of... one farmer excavated in Scandinavia... is genetically most similar to extant southern Europeans, contrasting sharply to the [three] hunter-gatherers, whose distinct genetic signature is most similar to that of extant northern Europeans" -- interesting, but they need more independent replicates!

In Situ Evolutionary Rate Measurements Show Ecological Success of Recently Emerged Bacterial Hybrids

Robust self-replication of combinatorial information via crystal growth and scission "neither enzymes nor covalent bond formation are required for robust chemical sequence replication" but the error rate seems too high to evolve anything useful: "78% of 4-bit sequences are correct after two generations"

Antarctic and Southern Ocean influences on Late Pliocene global cooling "a major expansion of an ice sheet in the Ross Sea that began at ∼3.3 Ma, followed by a coastal sea surface temperature cooling of ∼2.5 °C,"

Role of the Bering Strait on the hysteresis of the ocean conveyor belt circulation and glacial climate stability

April 20, 2012

This week's picks

Nuclear Genomic Sequences Reveal that Polar Bears Are an Old and Distinct Bear Lineage

Structural diversity in social contagion

A Yeast Prion, Mod5, Promotes Acquired Drug Resistance and Cell Survival Under Environmental Stress

9,400 years of cosmic radiation and solar activity from ice cores and tree rings

Synthetic Genetic Polymers Capable of Heredity and Evolution

April 19, 2012

A taste of Darwinian Agriculture

My book on Darwinian Agriculture should be available in June. If you think you might want to read it, Princeton University Press has information, including a PDF of the first chapter.

April 17, 2012

Scientific retractions and competition for jobs

According to a recent article in the New York Times:

"the journal Nature reported that published retractions had increased tenfold over the past decade"

The article suggests that this may be partly due to scientists cutting corners (fraud, or sometimes choosing to publish more papers rather than to check results more carefully), due to increased competition for jobs:
"In 1973, more than half of biologists had a tenure-track job within six years of getting a Ph.D. By 2006 the figure was down to 15 percent."

Over the same period, competition for research grants has becoming increasingly fierce. Meanwhile, universities that hired many more faculty and built many more buildings than needed for teaching (anticipating lots of research grants from which university administration takes up to 50%) deny tenure to even excellent teachers and researchers who don't bring in enough grant money.

Some scientists suggest that these problems could be solved by exponentially increasing research funding to match the exponential increase in PhDs, just as some economists suggest that an exponential increase in food production is the solution to exponentially increasing population. But neither of those is going to happen. So, the article suggests, maybe we should:

"move away from the winner-take-all system, in which grants are concentrated among a small fraction of scientists. One way to do that may be to put a cap on the grants any one lab can receive. Such a shift would require scientists to surrender some of their most cherished practices -- the priority rule, for example, which gives all the credit for a scientific discovery to whoever publishes results first."

I don't think the link between winner-take-all and the "priority rule" is so clear. I can only think of two cases, over my whole career, where someone beat me to a specific result I was working on also. But labs with more resources than mine get more total results, which helps them out-compete me for grants, so that they get even bigger. Should we limit this process of cumulative advantage?

We're talking about tax money here, so we should do what's best for society as a whole, not necessarily what's best for individual scientists or aspiring scientists. But there may be societal benefits to making scientific careers more achievable, or at least perceived as more achievable. Kids who aspire to be scientists rather than football players may learn more in school and subsequently make more contributions to society, whether or not they actually become scientists.

Even leaving such role-model benefit aside, data from NIH show that labs with less total funding produce more papers per dollar. So the public might get more research per tax dollar by spreading the wealth around to more labs.

April 5, 2012

Perverse incentives in science

Economist Paula Stephans has a stimulating commentary in Nature this week, arguing that "Counterproductive financial incentives divert time and resources from the scientific enterprise."

For example, she says that cash incentives offered in China, South Korea, and Turkey have led to a 46% increase in submissions to Science, but no increase in publications. Officials in offending countries are presumably indifferent to the workload of Science reviewers, so is this really a perverse incentive, from their point of view? It could be, if papers from their country get such a bad reputation that even good papers suffer guilt by association.

She argues that graduate students should be supported mainly by broad training grants rather than research assistantships tied to specific research projects, because the training grants have lower overhead costs (8% versus 50%). This is nonsense. Unless we somehow reduce the actual costs of educating grad students, which would likely reduce the quality of their education, the money has to come from somewhere. Universities subsidize training-grant students by diverting money from 50%-overhead grants to cover the difference between 8% and the actual cost of those students. Eliminate the 50%-overhead grants, and the whole thing falls apart. On the other hand, she may be right that students in training grants get a better education. If so, maybe we should support more training grants, but we'll have to pay for them.

But is the 50% overhead rate fair? It may be too high. I would argue that the socially optimum overhead rate is the rate at which university administrators would accept a grant iff they thought it would increase the university's (or their own) prestige, not just for the money. At 50%, they would probably accept a grant to study almost anything (the healing power of prayer, say), so long as incremental costs of providing facilities for that research were much less than 50% of the grant amount. On the other hand, an administrator at UC Davis told me not to apply for USDA grants, because they only paid 15% overhead. So the fair overhead rate is probably somewhere between 15% and 50%. 8% isn't enough to cover even the marginal costs of research.

Stephans discusses various perverse incentives that make individual labs grow too big -- smaller labs publish more per dollar -- which she attributes to "bonuses" based on external funding. I don't think eliminating such bonuses would much effect. The real problem is that grants tend to go to those who have published the most, not those who have published the most per dollar. So big grants lead to more big grants, a process known as "cumulative advantage." I discuss this problem in more depth in the "Selection Among Ideas" chapter of my forthcoming book, Darwinian Agriculture.

Stephans also discusses perverse incentives that make universities build too many buildings. If they borrow money for new buildings, they can include the interest on the loans in their overhead costs. In addition to this perverse institutional incentive, there may be perverse individual incentives. The administrator who takes credit for the new building puts it on her CV and uses it to get a higher-paid job, leaving the costs of maintaining the building (as state and federal funding declines) to her successors.

The issue of "training more PhDs than there are jobs" is more complex than Stephans implies. What's best for the millions whose taxes support research universities isn't necessarily best for individual students. Click "careers in science" for my past discussions of this topic.