Science and the media: 14 - 20 May

MAY 20, 2011

Steve Corneliussen’s topics this week:

Science magazine and New York Times coverage of a study of “deliberate practice” in teaching college physics
New York Times front-page coverage of major findings about exoplanets
Nature editors’ advocacy of naming the present geological epoch anthropomorphically
Science magazine’s post-Fukushima review of the state of low-dose radiation biophysics
A mysterious silence in the climate wars

College physics: two-way engagement vs. one-way lectures

“As a psychologist, I’m ashamed that it is physicists who are leading this effort, and not learning scientists,” admitted James W. Stigler, a UCLA psychology professor, to the New York Times. Here’s the Science magazine abstract for the study in question, “Improved Learning in a Large-Enrollment Physics Class":

We compared the amounts of learning achieved using two different instructional approaches under controlled conditions. We measured the learning of a specific set of topics and objectives when taught by 3 hours of traditional lecture given by an experienced highly rated instructor and 3 hours of instruction given by a trained but inexperienced instructor using instruction based on research in cognitive psychology and physics education. The comparison was made between two large sections (N = 267 and N = 271) of an introductory undergraduate physics course. We found increased student attendance, higher engagement, and more than twice the learning in the section taught using research-based instruction.

The study has been reported and assessed in both the online Science magazine news article “A Better Way to Teach?” and in the New York Times piece “Less Talk, More Action: Improving Science Learning.”

The Science piece summarizes:

Any physics professor who thinks that lecturing to first-year students is the best way to teach them about electromagnetic waves can stop reading this item. For everybody else, however, listen up: A new study shows that students learn much better through an active, iterative process that involves working through their misconceptions with fellow students and getting immediate feedback from the instructor.

The research, appearing online . . . in Science, was conducted by a team at the University of British Columbia (UBC), Vancouver, in Canada, led by physics Nobelist Carl Wieman. First at the University of Colorado, Boulder, and now at an eponymous science education initiative at UBC, Wieman has devoted the past decade to improving undergraduate science instruction, using methods that draw upon the latest research in cognitive science, neuroscience, and learning theory.

In this study, Wieman trained a postdoc, Louis Deslauriers, and a graduate student, Ellen Schelew, in an educational approach, called “deliberate practice,” that asks students to think like scientists and puzzle out problems during class. For 1 week, Deslauriers and Schelew took over one section of an introductory physics course for engineering majors, which met three times for 1 hour. A tenured physics professor continued to teach another large section using the standard lecture format.

The results were dramatic: After the intervention, the students in the deliberate practice section did more than twice as well on a 12-question multiple-choice test of the material as did those in the control section. They were also more engaged—attendance rose by 20% in the experimental section, according to one measure of interest—and a post-study survey found that nearly all said they would have liked the entire 15-week course to have been taught in the more interactive manner.

The Times piece, after offering an equivalent summary, goes on to report criticisms. It quotes Daniel Willingham, a psychology professor at the University of Virginia: “The whole issue of how to draw on basic science and apply it in classrooms is a whole lot more complicated than they’re letting on.” The Times adds that he “said that, among other concerns, the study was not controlled enough to tell which of the changes in teaching might have accounted for the difference in students’ scores.”

The Times also quotes Stigler concerning the possible biasing effect of having the “deliberate practice” teachers serve also as the study authors: “This is not a good idea, since they know exactly what the hypotheses are that guide the study, and, more importantly, exactly what the measures are that will be used to evaluate the effects. They might, therefore, be tailoring their instruction to the assessment—that is, teaching to the test.”

But the Times also quotes Stigler’s opinion that “the authors are pioneers in exploring and testing ways we can improve undergraduate teaching and learning"—which is why he’s “ashamed” that his own colleagues didn’t lead the effort.

The news obviously calls to mind two buzz phrases from the science-outreach realm: the deficit model, in which scientists seek to defray citizens’ knowledge deficit with one-way lecturing to captive audiences, and the engagement model, involving two-way interactions. Nowhere in either news article do those terms appear, but it’s clear that the pedagogical researchers’ “deliberate practice” overlaps substantially with the engagement model and contrasts sharply with the deficit model.

New York Times front page reports unbound or distant Jupiter-mass objects

As highlighted on the New York Times front page, as mentioned only in a single sentence in the Wall Street Journal‘s daily “What’s News” roundup, and as ignored altogether in the Washington Post, this week’s Nature carries the report “Unbound or distant planetary mass population detected by gravitational microlensing” plus the companion commentary “Astronomy: Bound and unbound planets abound.”

The Nature report’s authors are the Microlensing Observations in Astrophysics Collaboration, from New Zealand and Japan, and the Optical Gravitational Lensing Experiment Collaboration, from Poland and Chile. They announce “the discovery of a population of unbound or distant Jupiter-mass objects.”

As the Times‘s Dennis Overbye explains it , the discovery is “that space [is] littered with hundreds of billions of planets that [have] been ejected from the planetary systems that gave them birth and either [are] going their own lonely ways or [are] only distantly bound to stars at least 10 times as far away as the Sun is from the Earth.”

Overbye reports that astronomers “said the results would allow them to tap into a whole new unsuspected realm of exoplanets . . . causing scientists to re-evaluate how many there are, where they are and how they are created, even as astronomers immediately began to ponder whether the new planets in question are in fact floating free or are just far from their stars.” He explains the gravitational microlensing method as relying “on the ability of the gravitational field of a massive object . . . to bend light and act as a magnifying lens, as predicted by Einstein’s general theory of relativity.”

Nature editors: Recognize the Anthropocene to “focus minds”

Nature’s editors this week are seeking to intensify the technopolitics of the word Anthropocene—the anthropomorphizing name that, on behalf of all of science, the International Commission on Stratigraphy is considering for the present geological epoch. The most obvious political implications involve climate, but that’s far from the whole story.

As reported here last winter, the abstract for the introductory piece in a special issue of Philosophical Transactions of the Royal Society A: “The Anthropocene: a new epoch of geological time?” summarized the question:

Anthropogenic changes to the Earth’s climate, land, oceans and biosphere are now so great and so rapid that the concept of a new geological epoch defined by the action of humans, the Anthropocene, is widely and seriously debated. Questions of the scale, magnitude and significance of this environmental change, particularly in the context of the Earth’s geological history, provide the basis for this Theme Issue. The Anthropocene, on current evidence, seems to show global change consistent with the suggestion that an epoch-scale boundary has been crossed within the last two centuries.

A 28 February New York Times editorial argued that a “strong case” exists for the proposed name. Now a Nature editorial argues, “Official recognition for the Anthropocene would focus minds on the challenges to come.” It asserts: “Humans may yet ensure that these early years of the Anthropocene are a geological glitch and not just a prelude to a far more severe disruption. But the first step is to recognize, as the term Anthropocene invites us to do, that we are in the driver’s seat.”

Building on a Nature news article from a week earlier, the editors offer this summary of the science:

Human activity is set to leave an indelible mark on the geological record. Deforestation, mining and road building have unleashed tides of sediment down rivers and onto the ocean floor. Fossil-fuel use and land clearance have already emitted perhaps a quarter as much carbon into the atmosphere as was released during one of the greatest planetary crises of the past, the Palaeocene-Eocene Thermal Maximum 55 million years ago. Now, as then, corals and other organisms are recording a global carbon-isotope shift. The increasing acidification of the oceans as they absorb carbon dioxide will dissolve carbonate from deep sediments, and what is likely to be the sixth great mass extinction in Earth’s history will gather speed, adding vivid new markers to the record.

It’s the technopolitical dimension, however, that characterizes the editorial. The editors want more than an apt scientific name; they want an apt scientific name that will generate action by reframing environmental issues.

They ask, is “it wise for stratigraphers to endorse a term that comes gift-wrapped as a weapon for those on both sides of the political battle over the fate of the planet?” Their answer is yes. “Official recognition of the concept would invite cross-disciplinary science.” That’s the scientific dimension. To that dimension they add an explicit technopolitical dimension: “And it would encourage a mindset that will be important not only to fully understand the transformation now occurring but to take action to control it.”

Science magazine: “Fukushima Revives The Low-Dose Debate”

Front-page articles this week showed that Fukushima continues to command attention. On Wednesday, the New York Times offered “In Japan Reactor Failings, Danger Signs for the U.S.” The Wall Street Journal offered “Fresh Tales of Chaos Emerge From Early in Nuclear Crisis.” Now Science magazine has published a lengthy post-Fukushima analysis of the vexing challenges in developing scientific understanding of low-level radiation exposure.

“Radiation spiked 4 days after the first explosion,” the article explains, but since then, “radiation levels have ebbed as short-lived radionuclides, such as iodine-131 with a half-life of 8 days, decay into stable isotopes.” On the ground lie “small amounts of cesium-134 and cesium-137, isotopes with half-lives of 2 and 30 years respectively.” Now “several thousand of Fukushima’s 2 million residents have been thrust into the middle of a vigorous scientific debate about the health effects of long-term exposure to low levels of radiation.”

Science summarizes some of that perennial debate’s central questions:

Some researchers believe even unavoidable background radiation can be a factor in causing cancer. Others argue that tiny doses of radiation are not harmful. Some scientists even claim that low doses, by stimulating DNA repair, make you healthier—an effect known as hormesis.

There’s hope, the article says, that despite difficulties like sample size and insufficient controls for various influences, studies in Fukushima “could help clarify the picture.” The article summarizes the biophysics of radiation harm, mentions studies that followed Hiroshima and Nagasaki, laments inadequacies in studies of Chernobyl’s effects, and cites animal experiments that seem to find low doses benign. It describes nascent post-Fukushima study efforts, and reports scientists’ “hope [that] a respected entity will organize a high-quality research plan involving all levels of government.”

But within an ending that recalls the perennial vexations of radiation-exposure studies, the article adds:

Some researchers doubt that any study in Fukushima, no matter how well devised, will reveal much. The radiation exposure of the general population “is too small to give a statistically significant increase in stochastic effects such as cancer,” argues Ohtsura Niwa, professor emeritus of radiation biology at Kyoto University.

National Research Council re-emphasizes climate; Wall Street Journal editors silent

Late last week, the National Research Council published a report that warns, as the NRC’s summary announcement puts it, that “the risk of dangerous climate change impacts is growing with every ton of greenhouse gases emitted into the atmosphere.” The NRC reiterated that a “pressing need” remains “for substantial action to limit the magnitude of climate change and to prepare to adapt to its impacts.”

Early this week, the Washington Post published the editorial “Climate change denial becomes harder to justify.” It appealed for the NRC report to be heeded—and it harshly criticized Republicans and others for not heeding.

About a century ago, Arthur Conan Doyle published the story “Silver Blaze,” in which Sherlock Holmes identified “the curious incident of the dog in the night-time.” From a dog’s silence during the disappearance of a race horse, Holmes inferred much.

But I’m no Sherlock Holmes, so all I can do—in recycling the old “dog that didn’t bark” cliché—is report the dog that didn’t bark: the Wall Street Journal editorial page. I have no idea why the WSJ‘s editors and opinion writers have remained silent about the NRC report, given that its tone and content constitute a direct challenge targeted precisely at them. (Nor, by the way, am I Holmes enough to explain why the WSJ‘s guide to climate change, as I think it was called, has disappeared from the online editorial page.)

The Post‘s editorial adds to the challenge to the WSJ. Here are three examples of its harshness:

"[T]he Republican Party, and therefore the US government, have moved . . . far from reality and responsibility in their approach to climate change.”
“Seizing on inevitable points of uncertainty in something as complex as climate science, and on misreported pseudo-scandals among a few scientists, Republican members of Congress, presidential candidates and other leaders pretend that the dangers of climate change are hypothetical and unproven and the causes uncertain.”
“Climate-change deniers . . . are willfully ignorant, lost in wishful thinking, cynical or some combination of the three. And their recalcitrance is dangerous, the report makes clear, because the longer the nation waits to respond to climate change, the more catastrophic the planetary damage is likely to be—and the more drastic the needed response.”

The Post‘s editorial concludes this way:

Every candidate for political office in the next cycle, including for president, should be asked whether they disagree with the scientific consensus of America’s premier scientific advisory group, as reflected in this report; and if so, on what basis they disagree; and if not, what they propose to do about the rising seas, spreading deserts and intensifying storms that, absent a change in policy, loom on America’s horizon.

If the Wall Street Journal editorial page should decide after all to accept a new battle in the technopolitical climate wars, I’ll play the role of Dr Watson and report it.

Steven T. Corneliussen, a media analyst for the American Institute of Physics, monitors three national newspapers, the weeklies Nature and Science, and occasionally other publications. His reports to AIP are collected each Friday for “Science and the media.” He has published op-eds in the Washington Post and other newspapers, has written for NASA’s history program, and is a science writer at a particle-accelerator laboratory.