Sunday, September 17, 2017

A Modeler Thinks About Assessment

As a lecturer and DBER fellow, I hear a lot about assessment. Instructors are told that they must align what they teach with the questions that are going to be on their exams, that students shouldn't encounter a question type on an exam that they haven't previously learned how to answer.

I think this is profoundly wrong for one simple reason: assessment is a modeling problem.

Think of your knowledge of some topic -- evolution or cell metabolism or ordinary differential equations --  as a network of related concepts, facts and techniques in your mind. The beginner's network might be missing some important connections and contain extraneous, misleading ones. The expert's network is rich but well-organized.

In assessment that goes beyond simple factual questions like "what are mitochondria?", we are implicitly trying to find out whether a student's network is more like the one on the left or the one on the right. The more expert-like the network, the better the student understands our subject.

Of course, we can't observe this network directly. To a teacher, a student's mind is a black box. Therefore, we poke and prod the black box by asking the student questions and use the answers to build our own models of the student's knowledge network. Particularly valuable are those questions whose answers are easy to figure out if subject matter knowledge is complete and well-organized but difficult or impossible otherwise. If a student answers these types of questions correctly, they probably understand the subject well.

Unless, of course, the student has explicitly learned how to answer the question that you asked without figuring it out. Then the process is short-circuited and we are left without a way of assessing what a student actually understands. Ben Orlin writes about this in Math with Bad Drawings:

Need to prove these triangles are congruent? Do this. Need to prove that they’re similar? Do that. Need to prove X? Do Y and Z. I laid it all out for them, as clean and foolproof as a recipe book. With practice, they slowly learned to answer every sort of standard question that the textbook had to offer.

Months passed this way. But something wasn’t clicking. I kept seeing flashes and glimpses of severe misunderstandings—in their nonsensical phrasings, in their explanations (or lack thereof), in their bizarre one-time mistakes. Despite my best intentions, something was definitely wrong. But I didn’t know what.

And, more worryingly, I didn’t know how to find out.

I’d already coached them how to answer every question in the book. How, then, could I diagnose what was missing? How could I check for understanding? For every challenge I might give them, every task that might demand actual thinking, I’d equipped them with a shortcut, a mnemonic, a workaround. The questions were like bombs defused: instead of blasting my students’ thoughts open, they now fizzled harmlessly.

Orlin is describing his mistakes as a novice teacher. But this is the inevitable consequence of the "alignment" being pushed by proponents of scientific teaching. They would probably say that the student should initially figure out the procedure instead of being taught it, and this might indeed be better (or not), but it remains true that when the exam rolls around, all we will see is how well the students remember what they were taught. We will have lost our tools for modeling their minds and assessing their understanding.

Saturday, March 07, 2015

You Don't See Me as Disabled? Awesome!

I have a disability that's about as visible as they come. I've got the powerchair, the involuntary movements, a cerebral palsy accent, the works. Rather understandably, the first thing you'll notice about me if we meet is my CP.

Yet, contrary to what many people are saying these days (primarily about race, like here and here), I love it when friends and colleagues say they don't see me as having a disability. Possibly the best comment to this effect that I've heard came from a long-time mentor who said, with reference to my powerchair, "I don't care how my employees get to work".

It's not that there's something wrong with these people's eyesight -- and even if there was, I've run over most of them enough times for them to notice that something was up. And it's not that they don't acknowledge that my disability sometimes causes difficulties. We talk about these things when they are relevant. It's that, as dramatically evidenced by the "invisible gorilla" experiment, seeing is a matter of attention. And my disability is low on my friends' lists of interesting and important things about me, just as it is on mine.

I am a human being, a scientist (specifically, an ecologist), a teacher and curriculum nerd, a rock climber, an atheist, a vegetarian, and a world federalist. I like science fiction, country music, kayaking, and learning Brazilian jiu jitsu. All these things are more interesting and, in various ways, closer to the core of who I am than the incidental fact of having had encephalitis at 4 months. Yes, my disability interacts with these identities in various ways, sometimes rather obviously. And yes, it sometimes affects my perspective on things. But it's incidental to the person I fundamentally am.

[EDIT: A paragraph that really should have been here to begin with]: My disability (like my gender, race, etc.) is entirely accidental. Therefore, it can't be fundamental to who I am. If it was fundamental, it would mean that who I was was determined by circumstances rather than the gradual process of shaping myself into the person I want to be (in interaction with my environment, of course). That would be abdicating a responsibility that simply cannot be abdicated.

It's OK if you notice my disability. After all, it's pretty hard to miss. But after we've interacted for a while, I hope your attention shifts to other things. And if you say that you don't see me as disabled, I will conclude that you're seeing me as me.

Sunday, January 19, 2014

A Cliche That Kills

Read any news article on fitness and two types of commenters almost inevitably appear. One is the person who feels compelled to give WAY too much information about their personal regimen. The other is the commenter who writes, "But I'm disabled and I can't exercise".

The first of these is merely annoying. The second is promoting a cliche that kills people.

While doing some random Googling over the weekend, I came across two studies that should grab the attention of everyone who has a disability or is in any way associated with the fitness world. Both have to do with cerebral palsy (sorry, but that's what I have, so it grabs my interest), but the conclusions should apply to many physical disabilities.

The first of these is a study from 1999 that looks at the causes of death of people with CP. While some of these are unsurprising to those familiar with the condition (many deaths are due to pneumonia), one finding in particular should be shocking. In the California population these researchers studied, people with cerebral palsy were approximately twice as likely to die from coronary artery disease as people in the general population. They were also 2-5 times more likely to die from stroke. And these numbers are actually conservative, as I'm leaving out the ambiguous 0-34 age group.

These deaths are not just happening among the old. They apply to the 35-54 and 55+ age classes.

To drive this point home, we can look at a French study that just came out and got similar results. This article conveniently included graphs showing at what ages deaths from various causes occurred among people with CP contrasted with the general French population. Here is the graph for circulatory disease.
What this graph shows is that the vast majority of deaths from circulatory disease in the general population happen at ages 75 and older. But among people with CP, they happen at almost all ages. People in their 30s are dying of cardiovascular disease!

This is the kind of graph that ought to make us furious. Because, despite all the caveats that could be put in (maybe preterm birth has an effect, maybe stress has an effect, probably not all these deaths are from atherosclerosis), we do know something about preventing heart disease and stroke. We know that food and fitness are both major players.

I will say little about diet, except to note that, strictly speaking, it's body fat percentage that matters, not weight. You can have the stereotypically skinny CP body and still be metabolically obese because many of us have little muscle mass and can carry a fair amount of fat without showing it or appearing as overweight by BMI standards. Skin fold measurements, which should be done by a professional, and measures related to waist circumference, which can be done at home, are both more informative and potentially more wheelchair accessible than scales. And it's hard to be too disabled to eat better.

I will say more about exercise, because this is where the cliche does its damage. At the risk of sounding like those TMI commenters, I will first say a little about myself. I have a form of cerebral palsy that affects my balance and upper body control. I can walk with assistance but use a powerchair to get around. Also, I currently climb at a rock wall at least once a week and do weight training twice a week and cardio (exercise bike or rowing machine) 2-3 times a week.

Working at a university with a good gym and having a mini-gym in my apartment building helps me to be this active. Not everybody has this access, but everybody should be looking for something. Set up something at home or check out a few gyms and pick one that's accessible and suits your style and budget. The National Council on Health, Physical Activity, and Disability website has tons of resources.

"But I can't exercise!" Unless you're completely paralyzed, that's probably not true. (If you've been told by a doctor not to exercise, seek a more detailed explanation of why and consider a second opinion.) Start where you are and work up little by little. When I began using the rowing machine as a college freshman, after more than two years of inactivity, I started off with five minutes and went up by a minute a week. When I got to ten minutes, I started going up by two minutes a week. With these barely noticeable increments, I was soon doing a solid 20 minutes.

Strength training is also very beneficial and can be more accessible than aerobic exercise because you can choose from many exercises at various levels of difficulty. And it carries many of the same health benefits! Actually, you should do it either way, for the reasons laid out at this Mayo Clinic website. Ignore the sometimes macho culture and start where you are, moving up in small increments. (Consider hiring a trainer for a few sessions if you need help designing a program.) But do move up! If you need to start an exercise with five pounds -- or even one pound -- that's fine. Just don't stay there. Speaking from experience, being able to handle more weight than a non-disabled person is fun!

Weight machines can help overcome some disability-related limitations. I was never able to do sit-ups until I started using an ab machine with weights and gradually brought the weight up. Now, they're not a problem. And, as counterintuitive as this is, strength training doesn't exacerbate spasticity.

 "But people will be looking at me!" Yes, but not in the way you fear. They'll be admiring you. A person with an obvious disability who works out, at whatever level, commands respect. And your presence can make others with and without disabilities more comfortable. The overweight or inexperienced person who just started going to the gym might see you there and think, "If they can do this, I can do this". That's a powerful thing.

Those of you working in fitness-related fields should consider what you can do to improve accessibility. (The NCHPAD website has ideas for doing this.) When I started doing strength training as a University of Georgia grad student, the weight room staff was easily able to provide help because of their room setup. At UCLA, getting the logistics worked out took a bit of time, but we made it work. Think of what kind of support people might need and what your facility can provide.

Ultimately, all of us, with and without disabilities, should start treating access to fitness as a civil rights issue. Because staying alive is as fundamental a right as they come.

Saturday, February 04, 2012

Why "No True Scotsman" is Not a Fallacy

Hang around an atheist discussion on the Internet long enough and eventually you'll see a poster being accused of committing the dreaded "No True Scotsman" fallacy. This typically happens when someone makes a statement like, "No true Christian rapes children". The hapless speaker is then accused of committing a fallacy and possibly being intellectually dishonest to boot. But are they?

According to Wikipedia, the original example of the alleged fallacy was the following:
Imagine Hamish McDonald, a Scotsman, sitting down with his Glasgow Morning Herald and seeing an article about how the "Brighton Sex Maniac Strikes Again." Hamish is shocked and declares that "No Scotsman would do such a thing." The next day he sits down to read his Glasgow Morning Herald again and this time finds an article about an Aberdeen man whose brutal actions make the Brighton sex maniac seem almost gentlemanly. This fact shows that Hamish was wrong in his opinion but is he going to admit this? Not likely. This time he says, "No true Scotsman would do such a thing." —Antony Flew, Thinking About Thinking: Do I sincerely want to be right?
Another common example involves trivial actions, like putting sugar on oatmeal. Later, we'll see why such examples miss the point.

In this post, I will use a non-trivial example that doesn't involve Scotsmen: "No true scientist falsifies data". The sentence rings true, but I know some scientists have falsified data. Thus, I would never say, "No  scientist falsifies data" but have no problem saying, "No true scientist falsifies data". That's because the two sentences are not synonymous.

Being a scientist has an important ethical dimension. Here's the key point: we often use the word "true" to highlight the moral aspect of group membership. A "true scientist" is someone who sees science as more than a career, someone who understands the ethics of science and does their best to follow them. To Hamish McDonald, being a Scotsman implies behaving in a certain way, which includes not committing horrendous sex crimes. Someone who lives in Scotland and commits such crimes may be a Scotsman, but to Hamish, he is not a true Scotsman. We now understand why the oatmeal example is silly -- putting sugar on oatmeal has no moral significance that I can see.

Like any refinement of the subject of discussion, the word "true" may be used to avoid difficult or unpleasant conclusions or to win at all costs. But it is not intrinsically fallacious.

Friday, October 28, 2011

Science is Not a Game

Janet Stemwedel at Doing Good Science has been blogging about Marcus Ross, the young earth creationist who earned a mainstream Ph.D. in paleontology. She's trying to pin down exactly what scientists and science-minded people think is wrong with what he did. Where exactly is that gut feeling of something not being quite right coming from?

One of the possibilities she examines is that, "It’s wrong for Ross to maintain his young earth creationist beliefs after the thorough exposure to scientific theories, evidence, and methodology that he received in his graduate training in geosciences". Here, however, she says that young earth creationism is a religious belief, not a scientific one, and scientists typically have all kinds of non-scientific beliefs. This seems like a weak argument to me, as Ross' particular religious beliefs directly contradict scientific ones. This isn't a case of a scientist simply not applying their training to certain belief; it's a case of irreconcilable conflict.

Still, I think that the problem here goes deeper than that. I would argue that when Marcus Ross was doing his dissertation research, he was not doing science, despite using completely standard methods. Ross is not a scientist. He only plays one on TV.

I make this claim because I think that science is defined by its goals, not its methods. The goal of basic research is to improve your understanding of the Universe and share this understanding with others. Janet Stemwedel has referred to the "inferential machinery" of science several times in her blog series, but this machinery (to the extent that a general scientific method even exists) is only a tool. We do experiments, make observations and carry out statistical analyses because doing so is a fairly reliable method of learning about the natural world. If carrying out Ouija board seances while standing on your head was a better way of learning about the world, graduate students would have to master inverted Ouija board use.

This is how we can distinguish Ross from real scientists. His belief in young earth creationism was fixed, so he can't be said to have believed the conclusions in his dissertation. Therefore, Ross' understanding of the world was not and could not have been improved by his work. His research was only a pantomime of science -- maybe a good pantomime, but a pantomime nonetheless.

Monday, October 24, 2011

An Ethical Ad Blocker?

I just read George Monbiot's new essay about advertising and it got me thinking about how we might reduce ad exposure on the web. Like many people, I sometimes use an ad blocker. However, because I'm aware that the free content and services I depend on are paid for by advertising, I generally only use the blocker for sites with really annoying ads. Still, it would be better for the environment if we weren't exposed to so many messages telling us to buy stuff.

I propose that somebody develop a subscription-based ad blocker that would automatically make micropayments to the sites you visit. Content providers would register and the ad blocker plug-in would keep track of where you go on the web. (Ideally, for privacy reasons, this data would only be stored on your computer.) For practical reasons, you would probably pay a fixed amount of money each month. At the end of the month, the money would be divided among content providers according to how much you used them. If you disabled the blocker on certain sites, they wouldn't get any money.

So, what do people think? Is this workable? How would you modify the idea?

Saturday, October 01, 2011

On Not Being a Fish

There's a quote that's been making the rounds on the internet and elsewhere. Attributed to Albert Einstein, it says, “Everybody is a genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing that it is stupid.” (I very much doubt Einstein actually said this, as I've never been able to find a source for it. If you know where this quote comes from, please tell me in the comments.)

I have very mixed feelings about the "everybody's different" meme in education. On one hand, it's (trivially) true -- everybody IS different. On the other hand, I think it causes people to internalize their limitations as part of their identity. "Oh, I'm just not good at art/math/writing/music." Worse, it can cause teachers to give up on certain students.

I've been on the receiving end of this. In seventh grade, I started algebra and went from getting A's in math to getting C's. After a while, I concluded -- with ample support from people around me -- that I simply wasn't a "math person". This lasted until my fourth year of college when, for some reason, I decided to take a mathematical ecology class. To make a long story short, I bombed the midterm and was going to drop the course. When I went to see the professor and started talking about dropping, he just said, "Don't do that. That would be a mistake". He then sat down with me and we spent half an hour going over what I had gotten right on the test and what he thought that meant about my thinking. Result: I got help from a friend who was excelling in the course, earned a B+, and then went back and relearned the algebra and calculus I hadn't mastered earlier. In grad school, I successfully took several undergrad math classes and a large part of my research is now theoretical. So much for being a fish!

The fundamental flaw in the "fish trying to climb a tree" metaphor is the hidden assumption that people have fixed abilities and talents. But this is just wrong. My favorite example of the flexibility of our abilities is John Mighton, who was interested in both math and creative writing as a child, but was discouraged from pursuing them by some low grades and the belief that he would have to have been born a prodigy to do well in either field. Eventually, though, he became an award-winning playwright by deliberate practice, following the example of Sylvia Plath. While trying to make ends meet in theater, he started tutoring kids. His first student was a teenager who had been told by his teacher that he was too dumb to do well in math. (We'll return to him later.)

Mighton ended up creating a program called JUMP Math that allows kids who were far working below grade level to catch up and excel. Even more remarkably, when used as a full-class program, JUMP both increases achievement and drastically shrinks the gap between "stronger" and "weaker" students. It does this by combining careful step-by-step instruction with a strong emphasis on developing self-confidence.

Confidence in one's ability to learn is absolutely critical to learning. My grandfather, a retired engineer who was appalled at my calculus grades, once offered to pay for a tutor for me -- and I declined because I didn't think it would do any good. When a student doesn't believe their work will pay off, doing the minimum amount of work necessary to get by isn't laziness but a perfectly rational strategy. Why waste your time? Conversely, experiments have found that kids who are taught that intelligence can be developed with practice do better in school.

The bottom line: Most of us have the ability to excel in many fields and they can inform each other. While letting kids have time to explore their interests is certainly valuable, we should err on the side of educational breadth. So let's work to find worldchanging ways of teaching that work for everyone!

Oh, and about John Mighton? He ended up going back to school and earning a Ph.D. in mathematics. So did his first student.

Wednesday, December 12, 2007

What Am I Not Talking About?

Ahhh, finals. The urge to waste valuable study time on random websites is almost irresistible... so I'm not resisting it. Instead, I give you a list of mondegreens from England Dan and John Ford Coley's song "I'd Really Love to See You Tonight".

Original lyrics:
I'm not talkin' 'bout movin' in
and I don't want to change your life.

Misheard as:
I'm not talkin' 'bout:
  • forgivin'
  • the linen / the linens / my linens (How romantic!)
  • aluminum (chemical element #1)
  • a live in
  • bulimia
  • Lavinia
  • Malydian (huh?)
  • Bolivia
  • committing (At least that makes some kind of sense)
  • millennia / millennium /millenniums
  • museum
  • religion
  • the limit
  • 'ma lady' (Is that medieval or ghetto?)
  • John Lennon
  • Meridian
  • molybdenum (chemical element #2)
  • Mullet Inn (Come for the haircuts, stay for the fish?)
  • a wedding / no wedding
  • believin'
  • iridium (chemical element #3. We're into some really obscure ones now!)
  • my Lydia
  • my layin' ya (A little too bold for the mood of this song, wouldn't you say?)
  • my winnings
  • my livin' / the livin'
  • the women / my women (Again, not really a soft sell, is it?)
  • relating
  • relentin'
  • that idiot (The speaker or somebody else?)
  • that idiom
  • the lily liver (That doesn't even scan!)
  • the weather (Yes, Virginia, we can get more prosaic than "the linen".)
  • Aborigine
  • blamin'
  • oblivion
  • bellinin (Try googling it.)
  • merlinin (Is that a little Merlin?)
  • mood rhythm
  • the Lady in Green (Continuing the "mythology of the British Isles" theme.)
  • the Leonids
  • the lenient
  • the weekend
  • more than friends (Sensible but doesn't scan.)
  • no Indian (Next line: "And I don't want to join your tribe". Really!)
  • Marillion
  • but booty is
  • relivin'
  • melanin (More science!)
  • the lady

Monday, March 26, 2007

Silly Article About Mushroom Foraging

A promising-looking article about mushroom hunters in northern California focuses mostly on the "dark side" of the activity -- fines and possible poisonings. While these, particularly the latter, are real threats, people go overboard over them. One spectacularly silly quote, from the director of the Sacramento division of the California poison control system: "If you're going to eat mushrooms, buy them from the store." (Such a kicker sentiment!) Um, how about, "Don't eat anything you haven't positively identified and have an experienced forager accompany you if you're a beginner".

Another paragraph in the article is flat-out dangerous. "Serious hunters eat only what they can identify. Keller said once he learned to identify the distinctive color and sheen of death caps, he noticed them everywhere."

First, it's not just "serious hunters" who eat only the mushrooms they can identify, it's anyone who would rather not be poisoned. Many poisonings occur among immigrants who eat mushrooms that look like edible species from the old country. If you eat wild mushrooms, identify them. To species. And save a sample in case you do get sick.

The second sentence of the above pernicious paragraph is almost as bad as the first. The death caps are members of the genus Amanita and are actually quite easy to identify. In addition to having a fairly distinctive shape and a white spore print, Amanitas have a volva (an underground cup surrounding the stem) and, very often, scales on the cap and a ring around the stem. Maybe some species do have a distinctive sheen, but I wouldn't rely on that for ID.

If you're interested in getting out into the field to study (and eat!) mushrooms, check out the North American Mycological Association.

Saturday, February 24, 2007

This Made My Evening

Human solidarity and the power of international connections, both at their best.
LA Koreans Angry at Anti-Jewish Cartoon - "Korean-American community leaders said they plan to launch a protest against the publisher of a popular South Korean comic book that contains anti-Semitic images."...

Yohngsohk Choe, co-chairman of the Korean American Patriotic Action Movement in the USA, said, "I don't have words to describe the outrage I feel."

The group met Friday with Rabbi Abraham Cooper, associate dean of the Simon Wiesenthal Center, a Jewish advocacy group. Cooper said he would travel to Seoul on March 15 to raise concerns about the book.

Thursday, February 15, 2007

Oekologie Carnival

Hello and welcome to the (slightly delayed) February 15, 2007 edition of oekologie, the carnival of ecology and environmental science. Let's start off by clarifying what ecology actually is. Jeremy Bruno of The Voltage Gate starts off a series of basic ecological concepts by asking "What Is Ecology? ". My favorite definition is one of the oldest -- the study of how organisms interact with each other and with their environment. It is distinct from environmental science, which focuses on humans and, as Jeremy makes clear, it is a very broad field of study.

From here, let's move to posts on the science of ecology. James Millington at Direction not Destination presents a description of Characterizing wildfire regimes in the United States. Johan A. Stenberg of Insect-Plant Ecology presents a post on the open journal PLoS one and a call for less explanatory factors in experimental ecology. If you read ecology papers, you'll probably get behind that second one!

Yours truly has a post on feedbacks between climate and volcanic activity. You might say this is more Earth science than ecology, but I think anything on global self-regulation is ecologically relevant.

Greg Laden presents two evolutionary biology posts, The Evolution of Human Diet and Models of Sexual Selection. I learned quite a bit from these.

Finally, Marcia Bonta presents Grasslands of Central Pennsylvania. This excellent description of Pennsylvania grasslands and the forces that maintain them leads to our next subject area, natural history.

We start off with two posts from GrrlScientist at Living the Scientific Life. Gyroscopes Tell Moths How to Fly Straight explains, well, how gyroscopes at the base of moth antennae tell them how to fly straight and C'mon Baby, Light my Fire gives us a fascinating look at courtship among fluorescent spiders. Did you know fluorescent spiders existed? Cool! Reigh Belisama at Save The Ribble! has a nice post about a riverside nature walk, Locals Enjoy The Ribble's Winter Wildlife. Finally, Dave at Via Negativa gives us two posts, Bluestem and Forester-think: a brief primer. Both are thought provoking discussions on the relationships between humans and nature, which segues nicely to our third subject area, the environment.

Here, we start off with the ever-controversial subject of exotic species. Mike Bergin at 10,000 Birds, presents What is Wild?, which distinguishes between individual "fugitives" and established populations. On the other hand, Nuthatch at bootstrap analysis gives us shooting mute swans versus mute swans shooting blanks. What has more ethical standing, individuals or ecosystems?

Let's continue the water theme for a while. Don Bosch, The Evangelical Ecologist, presents The Desert Blooms, a piece about the recovery of marshes in Iraq and the establishment of Iraq's Ministry of Environment. Garry Peterson at Resilience Science discusses the role of an obscure fish in coral reef recovery from an algal-dominated state in Hidden Ecological Functions and Ecological Hysteresis. Jennifer Pinkley at The Infinite Sphere gives us Karst geology and water pollution and Sewage treatment plant on karst floodplain??? .

What can we do to protect the environment? Wenchypoo at Wisdom From Wenchypoo's Mental Wastebasket presents an appropriately contrarian post titled Green is Making Me See Red. Meanwhile, Vihar Sheth at green | rising discusses the environmental benefits of vegetarianism in You Are What You Eat.

On the political level, Justin Lowery at presents America: Pro-Immigration? Then Pro-Oil Dependence!. Vihar Sheth at green | rising presents Wasted Gas, on the use of landfill methane. John Feeney at Growth is Madness! points out that the problem isn't population or consumption, it's both, in An unholy matrimony. And Marcelino Fuentes at Biopolitical brings up the issue of scientific uncertainty at Crichton, Laurance, Lomborg, and their agendas.

We finish up on a light note. Avant News presents Ostrich Charged With Multiple Ostricides posted at Avant News, saying,

That concludes this edition. Submit your blog article to the next edition of oekologie using our carnival submission form. Past posts and future hosts can be found on our blog carnival index page.

Tuesday, January 02, 2007

Climate Affects Volcanoes, Volcanoes Affect Climate...

We know that volcanic eruptions can change the climate. The ash they throw up into the atmosphere blocks sunlight, cooling Earth. (The 1815 eruption of Mount Tambora in Indonesia caused the "Year Without a Summer" in Europe and North America -- and led to the writing of Frankenstein.) But can climate affect volcanic activity? Several discoveries reported in 2006 say yes.

The first discovery concerns isostatic rebound after glaciation. The rock continents are made of is less dense than the molten rock of the mantle, so continents float on the mantle like a rubber duck floats in your bathtub. Push down on the rubber duckie, or put an ice sheet on top of the continent, and they sink a little bit. When the ice sheet melts, the continent slowly rebounds to its former height. Patrick Wu of the University of Calgary have found links between isostatic rebound and seismic activity. Wu's research indicates that melting ice makes earthquakes, and maybe even volcanic eruptions, more likely as the crust rises to its new equilibrium height.

The work of Allen Glazner, of the University of North Carolina, is even more dramatic, finding a possible link between the dry climate of interglacial periods and supervolcanoes. Essentially, rainfall and groundwater can cool a volcano's magma chamber, making it less likely to build up the amounts of magma needed for a supereruption.

Let's look at this a bit more closely. Interglacial periods are warm and dry, which, according to this new work, makes volcano eruptions more likely. Volcanoes produce both suspended particles, which cool the Earth, and carbon dioxide, which warms it. Depending on which effect is more important in the long run, we may have a climate-stabilizing or destabilizing feedback loop. Either way, the connections are intricate and interesting. I look forward to learning more about this topic.

Monday, December 25, 2006

The Real Reason for "Happy Holidays"

Thank you, Bill O'Reilly. For the last two years, the normally pleasant holiday season has been polluted by heated arguments over a purported "War on Christmas". The allegation, for those of you living under rocks, is that political correctness is forcing Christmas out of the public sphere and "Merry Christmas" is being replaced by the generic "Happy Holidays".

Never mind that New Year comes just a week after Christmas and "Happy Holidays" can easily be understood to mean "Merry Christmas and Happy New Year". Christians who see themselves as victims of the "Happy Holidays" phenomenon insist that its purpose is to avoid offending folks who don't celebrate Christmas by avoiding explicit mention of it.

But is that really what's going on? I grew up in a secular Jewish family and was never offended by people wishing me a merry Christmas. Geoffrey Pullum of Language Log points out that neither are most people who don't observe the holiday. But there is more to saying "Happy Holidays" than just avoiding reference to a particular one.

Think back to the brouhaha over the removal of Christmas trees from Seattle-Tacoma Airport. (BTW, folks, a Christmas tree is not a Christian symbol. It's an adopted pagan custom, like Easter eggs.) That unfortunate decision was triggered by an Orthodox Jewish rabbi's request that the airport display a menorah along with its Christmas trees. The rabbi never asked for the removal of the trees. He simply wanted another holiday included.

The key word here is "included". Yes, very few non-Christians will be offended at hearing, "Merry Christmas" or seeing a Christmas tree. But it is nice to hear a greeting that you can interpret as including your holiday, whether that's Christmas, Hanukkah, Diwali or Eid al-Adha. In the same vein, I have no objection to public holiday displays, as long as they include symbols of many of the religions practiced in a community and secular holidays like New Year and Winter Solstice.

With this shift in viewpoint, I hope we can call a truce in the Christmas Wars. Now, can someone please explain "Season's Greetings" to me?

Wednesday, December 20, 2006

Tribute to Carl Sagan

Today is the ten-year anniversary of Carl Sagan's death and he is being memorialized in the blogosphere. Here is my own little contribution:

Sometime in the eleventh grade, I was browsing the shelves of my local public library and came upon a copy of Pale Blue Dot. That was not my first encounter with Carl Sagan's work -- I had read The Dragons of Eden a couple of years earlier -- but it was the one that took. I read Pale Blue Dot, renewed it and reread it. Reaching the renewal limit, I brought the book back -- and checked it out again on my very next library trip. (Of course, I was reading Sagan's other books at the same time.) I eventually bought a softcover copy of Pale Blue Dot, wore it out in a couple of years and finally invested in a hardcover edition.

What about that book captured my attention so durably? It wasn't just the fascinating descriptions of the Solar System or the luminous visions of future space exploration. What touched me the most was Sagan's sense of the unity of humankind. We occupied a tiny mote of dust in a vast Cosmos, and the way we treated each other had to reflect that. Against the backdrop of space, all the subgroups of Homo sapiens are essentially one. Sagan wrote:

Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there--on a mote of dust suspended in a sunbeam.

The Earth is a very small stage in a vast cosmic arena. Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds.

Our posturings, our imagined self-importance, the delusion that we have some privileged position in the Universe, are challenged by this point of pale light. Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves.

If you have a high-bandwidth connection, please watch the YouTube video below. Quite honestly, it gave me goosebumps.

Wednesday, December 06, 2006

Imagining the Future We Want

Chris Clarke of Creek Running North asked readers to describe what the world would look like "if our side won". We're not talking about getting out of Iraq or implementing Kyoto but about having a vision. What kind of world do we really want to live in?

Several years ago, I ran a few Future History Project workshops in which participants imagined the world they wanted to exist in a hundred years and then outlined its history. The article below describes one such experience. (WFA is the World Federalist Association, which has since transmogrified itself into the much less visionary Citizens for Global Solutions.)

Conversations for a Century
by Jane Shevtsov

What happens when we set aside the problems of the present and give ourselves permission to dream?

  "It is now the year 2102. What are your favorite things about the world right now?" I ask this question at the beginning of the Future History Project workshop Tad Daley and I are conducting at WFA's October 2002 assembly in Denver. The thirty or forty people attending spend the next five minutes writing about a time when the troubled years of the early 21st century are safely in the history books.
  Why are we indulging in these flights of fancy when there are so many pressing issues right here and now? When the president seems hell-bent on bombing an already suffering nation, when the global climate is changing unpredictably and the rate of extinction is higher than at any point in the past 65 million years, when tens of thousands of children die every day from fully preventable causes, what is the use of speculation about a better world a century hence?
  The very existence of these problems makes it important to dream of a world without them. Once we envision a world in which problems like these do not exist, we can see why they do not exist. And the Future History Project goes more deeply into this than most other visioning processes because Future History participants develop the history of that happy world of 2102. They draw a road map from here to utopia.

  Such grandiose plans can be difficult to get into. So right after brainstorming, I ask participants a simple question. I ask them what their community is like.
  My co-facilitator corrects me immediately. What do I mean by community?
  It is a good question, since even now, virtual communities are important and growing exponentially. So I define community as both physical neighborhood and any virtual communities to which you belong.
  After a few questions, the discussion takes on a life of its own. Occasionally Tad and I remind people of the ground rules -- if it's desirable and doesn't break the laws of physics, then it's possible; no miracles or aliens, "now" is 2102 -- but mostly we're just along for the ride, keeping order and taking notes but letting ideas flow.
  People speak of social contracts and sustainable architecture, of food and livelihood. This being WFA, government, particularly global government, gets much attention. (At a Future History Project, sometimes a person who has no idea world federalists even exist will be the first to bring up global government.) We discuss schools, families and values -- especially values. People seem eager to discuss a shift to more inclusive, communitarian values.

  After about 45 minutes, we shift gears. It is time for the hard part -- inventing the history of 2102. A timeline hangs on the wall and we try to fill it in, going backwards from 2102 to 2002. As co-facilitator, I try to get people to think in terms of logical steps -- A had to happen before B could occur -- but mostly people just want to fill in that blank sheet.
  And fill it in they do. We go to Mars in 2012. In 2032, a reformed UN General Assembly becomes a world government. By 2042, everyone uses renewable energy. And so on.

  It's over too soon. Ten minutes of written and shared reflection and we go our separate ways. But people leave inspired. Utopia is not impossible -- it's just very, very improbable. And the improbable happens.

Tuesday, October 24, 2006

The Creek is Running Again!

Creek Running North is back up after dealing with anonymous threats. What does the writer's dog have to say about it?
"When I brush Chris’ cactus plants
I sometimes wince or cry aloud,
But for an online thug? Fat chance.
My leg is lifted, and bow-wowed."

Monday, October 23, 2006

Threats Against a Blogger

Creek Running North, to which I have linked several times, is down. Its owner, Chris Clarke, who is an environmentalist and progressive activist, has had his dog threatened. From prior experience, Chris does not expect the police will be of any help. In a comment on Pharyngula (you'll have to scroll down), he writes:
"My blog is one of the least important things I do. Becky and Zeke are up top, and quite honestly Zeke's impending demise makes him edge Becky out, as he's edged me out in Becky's priorities. In descending order after that: a few good friends, my longer-term writing projects, political activism, my day job, hiking, my blog. I appreciate the fact that my blog has fans. But really now. My effective speech takes place at my day job and doing politics. I am not one of those people who has confused writing a blog post with political activism."
About the only thing I disagree with in that is the last sentence. If you have an audience, blogging can indeed be political activism. Although it probably won't influence decision-makers directly, it may well help awaken your fellow citizens. Chris' blogging has done this to me more than once.

This whole situation has made me think about threats to bloggers, particularly in repressive societies. The Committee to Protect Bloggers has shut down, although the people behind it are doing related work. The Electronic Frontier Foundation has some information on bloggers' rights, but it appears to be mostly written for US readers and toward avoiding civil lawsuits and other relatively mild consequences. Is there anything else out there, in the US or elsewhere?

Good luck, Chris, and I hope the creek starts running again soon.

Sunday, October 22, 2006

Rediscovering a Favorite Song

I have a confession to make: I don't like Charlotte's Web. At least, I didn't care for it in the third grade, when my class read it. (I disliked all fantasy and fairy tales at the time.) However, seeing the movie was completely different and one song from the film has stayed with me to this day. And a couple of days ago, I finally got around to looking it up.

The song is called "How Very Special are We" and is a gentle, poetic lyric about the seasons and the cycle of life. There doesn't seem to be a formal site of Charlotte's Web soundtrack lyrics, but a user going by TherealRNO has posted the words to "How Very Special are We" in an review. There's also a short clip of the song at

Here are the words:

How very special are we
For just a moment to be
Part of life's eternal rhyme
How very special are we
To have on our family tree
Mother Earth and Father Time

The summer larks return to sing
Oh, what a gift they give
The autumn days grow short and cold
Oh, what a joy to live

He turns the seasons around and so she changes her gown
But they always look in their prime
They go on dancing their dance of ever-lasting romance
Mother Earth and Father Time

How very special are we
For just a moment to be
Part of life's eternal rhyme
How very special are we
To have on our family tree
Mother Earth and Father Time...

The autumn days grow short and cold
It's Christmastime again
The snows of winter slowly melt
The days grow long
And then

He turns the seasons around and so she changes her gown
Mother Earth and Father Time
How very special are we
For just a moment to be
Part of life's eternal rhyme

Friday, October 13, 2006

Friday Random Ten

  • Emerald Rose, "Penny in the Well". A warm song about searching for fulfillment.
  • Tim McGraw, "Tiny Dancer". I like this version of the song.
  • Alabama, "Fiddle in the Band". Can you listen to this and not tap your toes?
  • John Denver, "Islands"
  • Jackson Browne, "Running on Empty". A very LA song about growing up.
  • Bruce Cockburn, "All the Diamonds in the World". Gentle and lyrical.
  • Vladimir Vysotsky, "Vyet Eto Nashi Gory (These are Our Mountains)". Russian song that tells of a WWII battle in which Soviet alpine fighters faced German soldiers they themselves had trained. Has anybody tried to translate Vysotsky into English?
  • John Denver, "Rhymes and Reasons". The first John Denver song I ever heard and still one of my favorites. Hopeful and comforting.
  • Trisha Yearwood, "Real Live Woman". An honest, solid song that matches Yearwood's style perfectly.
  • The Highwaymen, "Against the Wind". Good song, but I like Bob Seger's version better.

Now I'm off to the Smokies!

Tuesday, October 10, 2006

What Does It Feel Like to be On Top of a Nuclear Test?

Since North Korea claimed to have tested a nuclear weapon on Monday, geologists and policy wonks have been wondering why the tremor the detonation caused was so small. Was the bomb small, not very good, or fake -- simply a pile of regular explosives? While the authorities study and debate, I am struck by the surrealness of the situation. Human beings have weapons that imitate tectonic plate movements!

I grew up in southern California and have been through several earthquakes, including the magnitude 6.6 Northridge Earthquake in 1994. When I read about the North Korean nuclear-seismological debate, I wondered what it would feel like to be on top of an underground nuclear test.

To find out, I combined a Wikipedia chart of the Richter scale magnitudes of various earthquakes and explosions with a chart giving rough conversions between earthquake magnitudes on the Richter scale and their felt intensities on the Modified Mercali Scale. Here is the result.

EventRichter magnitudeTNT EquivalentIntensity
WWII conventional bombs1.5178 kg (392 lb)Detected only by seismographs
late WWII conventional bombs2.01 metric tonDetected only by seismographs
WWII blockbuster bomb

2.55.6 metric tonsDetected only by seismographs
Small atomic bomb4.01 kilotonResembling vibrations caused by heavy traffic.
atomic bomb
5.032 kilotonSleepers awakened and bells ring.
Little Skull Mtn, NV Quake, 19925.5178 kilotonsTrees sway, some damage from overturning and falling objects.
Double Spring Flat, NV Quake, 19946.01 megaton

General alarm, cracking of walls.
Northridge quake, 19946.55.6 megatonsChimneys fall and there is some damage to buildings.
Tsar Bomba, largest
thermonuclear weapon ever tested
~7.050 megatonsGround badly cracked and many buildings are destroyed. There are some landslides.
Landers, CA Quake, 19927.5178 megatonsGround badly cracked and many buildings are destroyed. There are some landslides.