Starts With A Bang! » Education Ethan Siegel's blog/video blog about Cosmology, the Universe, and everything else Sat, 04 Apr 2009 20:12:38 +0000 en There isn’t enough punishment for this Mon, 09 Feb 2009 22:25:22 +0000 ethan I normally try to keep my nose out of areas where I’m in over my head. In other words, there are areas where I’m an expert, and there are areas where I keep myself as informed as I can, but I have to rely on experts for their information. For instance, if you wanted to know about dark matter in our own galaxy, you should definitely come to me:

I’ve got expert knowledge on this, I’m familiar with what makes my findings scientifically rigorous and valid, and I know how to draw responsible conclusions based on the data in front of me. It is completely unreasonable to expect someone who isn’t an active researcher in theoretical astrophysics and cosmology to be an expert in the same way I am.

And by the same token, there are areas where I’m not an expert, such as what the incidences, symptoms, and causes of autism in children are:

So, to be informed, it should be reasonable for me to rely on the scientific findings of experts in that particular field of medical research. Now, I’ve talked before about the importance of being a good scientist, especially when your research can affect the health and well-being of others. So without further ado, I’d like to introduce you to someone you may not have heard of (unless you’re a huge fan of Bad Astronomy), Andrew Wakefield.

To give you the extremely quick version: in 1998, Dr. Andrew Wakefield published a very controversial paper following 12 children’s conditions at a clinic. His conclusion was that eight out of the twelve developed symptoms of autism after receiving their Measles, Mumps, and Rubella (MMR) inoculation. Since that piece of research, many millions of dollars have gone into researching the possibility of a link between vaccines and autism. Thousands of children have not been inoculated out of a fear of developing autism, and a few of those children have died as a result of contracting a disease for which a simple vaccine exists. There has been a huge grassroots movement that has sprung up among parents of autistic children, blaming the vaccine for their woes:

Now, over the last 11 years, overwhelming evidence has shown up that there is no link, not even a correlation (much less a causation) between vaccines and autism. But this past Sunday, an article came out in Wakefield’s home country of the UK, declaring the following:

MMR doctor Andrew Wakefield fixed data on autism

What? We have not just a scientist, but a medical doctor dealing with one of the fastest growing epidemics in medicine, falsifying results? And publishing them in a medical journal (the Lancet)? Remember that “eight out of twelve” statistic I quoted you earlier? Here’s what we get, upon further review:

Our investigation, confirmed by evidence presented to the General Medical Council (GMC), reveals that: In most of the 12 cases, the children’s ailments as described in The Lancet were different from their hospital and GP records. Although the research paper claimed that problems came on within days of the jab, in only one case did medical records suggest this was true, and in many of the cases medical concerns had been raised before the children were vaccinated.

The details are even worse. It turns out that after Wakefield’s “suggestion” that MMR, bowel disease/inflammation and autism were linked, the children were re-examined and diagnosed with these new bowel problems. I was unable to find US data, but in the UK, the number of confirmed measles cases in 2008 was 1,346. Want to know what the number of cases was in 1998, the year Wakefield’s paper was published? 56. One scientist’s false data has led to the resurgence of a disease that should be eradicated by this point. Nice move, Andrew, seriously.

That said, autism is a serious problem. We don’t know what causes it, we don’t know why the incidence of autism is so much higher than it’s ever been in the past, and these are things that need further investigation, absolutely. But not on a foundation of lies. And not by searching for a link that doesn’t exist with vaccines. Let’s do everyone justice, and have some sort of accountability for doctors and scientists who, through their actions (whether through ethical incompetence or unethical falsification), cause unnecessary death and disease among the general populace.

If you’re going to accept being lauded as an expert, you have to accept the responsibility of being an expert. Be honest. Be ethical. Or go do something else.

The Worst Scientist in History Tue, 30 Dec 2008 00:14:22 +0000 ethan There are many great, elegant, and simple theories and ideas that attempt to make sense of this Universe. Above all, many of these ideas are beautiful, and often the people who come up with them are brilliant.

Almost all of these great, elegant, and simple theories are wrong. This is important to remember and difficult for many scientists to accept. Most theories, no matter how well-conceived or how brilliant they are, will eventually fail to an experimental test that does not yield what the theory predicts.

The key, and this is a really hard part for anyone with an ego (and I am just as guilty of this as any other scientist), is admitting when your brain-child, your theory, is wrong. There are plenty of examples of this: Halton Arp and Fred Hoyle refusing to let go of their incorrect theories when it was shown that their theories were invalid and the Big Bang was more correct, Howard Georgi going into a deep depression when the proton didn’t decay as predicted by his theory of Grand Unification, and even Einstein refusing to abandon his idea of a classical unification of E&M and Gravity, ignoring all of the evidence for quantum theory.

Normally, when this happens, you have no reason to care. One person cannot hold up the scientific endeavor, cannot stop the tide of research and evidence as we gather more and more data and refine our understandings of the Universe. Science, technology, health, and medicine march forward.


Umm… right?

That’s what you think. Meet Trofim Lysenko. Biologist, agronomist, with a specialized interest and knowledge set in the field of inherited traits. Also, in my opinion, he is the worst and most dangerous scientist of the 20th Century. With his expert knowledge and status, he was able to promise increased crop yields following the famines and drop in food production in the USSR in the 1930s. In 1940, he was appointed director of the Institute of Genetics within the USSR’s Academy of Sciences, a position he held for 25 years.

What makes him the worst scientist in history? He was a denier of science. Despite overwhelming evidence in support of Gregor Mendel’s theory of genetics and inherited traits, Lysenko stuck to his own theories of hybridization instead. Lysenko’s theories became widely accepted in the USSR, and in 1948, scientific dissent from his theory of hybridization was outlawed.

It was not until about 15 years had passed, and crop productivity had failed to improve, that people in power realized that Lysenko was not fairly considering all of the evidence. Modern agricultural techniques were eventually adopted and Lysenkoism fell out of favor. But science in that field, especially in the USSR, was set back a good 20 years by Lysenko’s denial of the evidence.

Well, I must say, it’s a good thing that there’s nobody with any political influence who can make huge mistakes on issues of science policy. It’s a good thing that, in the USA, the scientific community is always consulted for their expert opinion on matters of national and international importance. And it’s a good thing that the opinion of one politician or one rogue scientist can’t dictate policy.


Umm… right?

A-ha! Three more weeks, America, just three more weeks. I have hope that this time, we’re getting it right.

Bad Science Makes Me Angry! Mon, 03 Nov 2008 19:01:53 +0000 ethan Okay, folks, I have two words I’d like you to think about: correlation and causation. When we say two things are correlated, we mean that somehow, when one of them shows a change, the other one changes, too. But it’s a big leap to say that one is causing the other.

Sometimes they do. Let’s say the rabbit population is exploding out of control. What do you do? Bring in a few foxes. Within a short time, because of all the food, the fox population will explode, and the rabbit population goes down. The population of rabbits and foxes are not only correlated, there is a causal relationship between them.

But sometimes two things coincide with each other, yet aren’t related. For example, the last Glacial Period reached its maximum extent 18,000 years ago, and then after a few thousand years, the ice retreated and the sea levels rose. Coincidentally, a very nearby, powerful supernova went off about 12,000 years ago.

Are these two events correlated? Yes, of course. They happened close to one another in time. But did one cause the other? Probably not; we know what causes supernovae (it isn’t anything on Earth) and we think other things caused the end of the last glacial period.

So today, there’s been a report all over the news:

Sexual content on TV is linked to teen pregnancy.

When I saw this, I thought that this was a highly interesting finding. Until I actually read the study. The science here is horrible. Let me summarize what the RAND corporation did, and why you should never trust a study like this.

  1. They followed the television viewing habits of 12-17 year olds for 3 years.
  2. They looked for a correlation between televised sexual content and pregancy (for girls) or responsibility for pregnancy (for boys).

And that’s all they did. And lo and behold, look at what they found!

Teens who were exposed to high levels of television sexual content (90th percentile) were twice as likely to experience a pregnancy in the subsequent 3 years, compared with those with lower levels of exposure (10th percentile).

Are you kidding me? That’s it? You found that teenagers who spend more time doing things associated with sex and show a higher interest in sex are more likely to be having unprotected sex? (Excuse me while I act half my age.) DUH! (Thank you.) Why is this not exactly what you’d expect? Of course they’re correlated! But why would you come to the illogical (and unsupported by any evidence) conclusion that watching sex on TV causes teenage pregnancy? Wouldn’t it be far more likely that the teenagers who pursue sexual content are the ones who are having more sex, or at least more unsafe sex? It’s not a good scientific technique: correlation does not imply causation!

Further research led me to uncover that this isn’t the first time they’ve published a report that has this abhorrent technique. Remember all the hoopla about teen violence and violent content on TV, the web, and video games? Same thing. They surveyed violent and nonviolent kids, surveyed their searches for violence, and (surprise, surprise) the ones who commit violent crimes are more likely to have searched for violence. Again, clearly, there’s a correlation. But it seems way more likely that the violent kids searched for violence, not that the kids who saw violence were more likely to go out and commit it.

The lesson? If you want to draw a conclusion about this, you have to test for it! They haven’t even devised a method for testing this. All they showed is that these things are correlated. You know, like global average temperature and pirates.

Give me a break.

If you miss the astronomy, the new Carnival of Space is up; I recommend you check it out!

Enemies of Science from Within? Mon, 15 Sep 2008 19:35:04 +0000 ethan Ever hear statistics like “95% of scientists believe in evolution” and think about the other 5%? Evolution is one of the greatest scientific success stories of all time, and has revolutionized the way we perceive the history of life on our planet. For a little refresher, check out Carl Sagan’s take on it below:

But somehow, even if you exclude mechanical engineers, computer scientists, and everyone except life scientists and earth scientists, there are still hundreds in the United States alone who believe that creation science is valid. In the past, these claims have been (rightfully) dismissed as scientifically invalid, and have been successfully kept out of science classrooms.

And then came this howler from overseas:

Professor Michael Reiss says that if pupils have strongly-held beliefs about creationism these should be explored.

Rather than dismissing creationism as a “misconception”, he says it should be seen as a cultural “world view”.

Why is this a big deal? Because Michael Reiss is the Director of Education for the Royal Society, the UK’s National Academy of Sciences.

Now, I’m all for education. I’m all for teaching about the misconceptions that go along with it, about the scientific method, and about explaining how we came to know the things we now accept as scientifically valid. I’m even for investigating the mechanisms that are known for evolution and those that are still up for grabs.

But embracing creationism as a cultural world-view in a science classroom? If you think that’s a good idea, why don’t you google for ‘creationism world view’ and see what comes up?

Whatever your personal feelings are on the matter, it certainly isn’t fit for a science classroom. And it’s shameful to have an organization as influential as the Royal Society advocating a position that denigrates the fundamental value of science like this. There’s been a mild outcry over this, but this is absurd! Why do I contend this? Because “creation science” is the enemy of science, and when your enemy attacks you, you need to defend yourself and fight back, not to capitulate. Michael Reiss is right about some things, like this:

When young people ask questions about creationism in science classes, teachers need to be able to explain to them why evolution and the Big Bang are scientific theories but they should also take the time to explain how science works and why creationism has no scientific basis.

But he’s unconscionably naive when he thinks that statements like “science teachers should endorse creationism as a worldview” aren’t going to be used by ‘creation scientists’ as evidence that creationism is valid. After all, this position has now been endorsed by the Royal Society!

Science is about discovering how the natural world works based on evidence gathered from the natural, observable world. That is not up for compromise. If my remedial 6th grade class at Crispus Attucks middle school in Houston, TX from 2000 can remember that, then maybe the director of education at the Royal Society should be held to advocating at least those standards.

Is the World Changing? Thu, 04 Sep 2008 03:52:03 +0000 ethan I write this in all seriousness. Do not be alarmed, you old men scientists. After all, you know that all the best scientists are men, real men, manly men! Always have been! Einstein! Maxwell! Newton! Galileo! And then you, and next your students, you wonderful, manly successor to these great men!

Believe it or not, this is the actual mentality in many academic cultures, prevalent among many professors at Universities where I’ve worked. And this is the mentality today, not fifty years ago.

But it may not matter for the next generation. And my evidence for this is the following anecdote:

I taught my second week of class today. I teach the Physics Laboratories to mostly biology majors: laboratory for the algebra-based introductory physics course. The students who take this are those who are going to medical school, pharmacy school, physical therapy school, and graduate school. Future doctors, pharmacists, physical therapists, and scientists. I teach all three sections of the class; about sixty kids altogether. And I say kids, but they’re mostly 20-year-olds. These classes — the people who get this far — they’re the ones who are going to succeed, they’re past the point where they get weeded out.

These classes are 75% female. My class today had four boys in it. Four! I said something about it, quietly, to a few of my students. And they started asking me, why is that? What is wrong with boys that they don’t make it this far? Their high school classes seemed to be pretty 50/50 split, genderwise. But by this point in college, their classes in sciences across the board were about 3:1 female to male, sometimes more.

I asked them (joking, I thought) whether there was maybe some way that boys were inferior to girls, and just weren’t going to make it as far as girls could? And then they rattled off a whole list of (mostly conceivable) reasons: boys take longer to mature, boys are generally more interested in things other than using their abilities to achieve in their career, boys don’t have the attention span to become adept at something as complicated as math and science. And I asked if they thought it could be genetic, and they finally realized that they were arguing that their gender was inherently better at math and science, with someone who’s a successful male scientist, and how absurd that whole idea had to be.

Seriously, how badass is that? What can people who think that men are in some genetic way superior to women say, when perhaps 50 years from now, we could have a scientific field that’s 75% women asking whether men have in some way become genetically inferior not only to women, but how they used to be?

Olympic Feets: How fast can you run? Thu, 21 Aug 2008 04:25:29 +0000 ethan 9.69 seconds in the 100 meter dash. 19.30 seconds in the 200 meter dash. Is this the limit? How fast can humans actually go?

Usain Bolt of Jamaica is now the world’s fastest man; these correspond to average speeds of 10.32 and 10.36 meters per second (or 23.09 and 23.18 miles per hour), respectively. That about as fast as I can go, too. Except I need a mountain bike to do it!

Well, you know what? That’s fast. But it isn’t even the fastest average speed that anyone’s ever run at. At the 1992 Olympics, the U.S. men’s team ran the 4×100m relay in a still-record 37.40 seconds, with Carl Lewis running his 100m split in a time of 8.80 seconds! That’s an average speed of 11.36 meters per second, or 25.43 miles per hour. Like I said before, fast.

But still not the fastest.

These are all very fast speeds, but they’re average speeds. What about instantaneous speed? At one particular instant, what’s the fastest a human can run? A typical 100-meter sprinter peaks just before the 60-meter mark, and tries to sustain that speed (or as close to it) as they can before they tire too much. Check out this sample of instantaneous speeds from a race between two of the (then) fastest humans:

The fastest clocked speed for a human is 12.1 meters per second (27.1 miles per hour) for Donovan Bailey, or fast enough to get a speeding ticket on most college campuses. You want to know how fast that really is? Try this:

Jump off a 25 foot cliff (or, equivalently, out of a third-story window) — the speed you hit the ground (or water) at is as fast as someone can run. You don’t sound impressed. Alright, try this on: if someone could sustain that speed for an entire mile, they would run a mile in two minutes and thirteen seconds. (Remember the “4-minute-mile” barrier?) If they could sustain that speed for an entire marathon, they would run the full 26.2 miles in 58 minutes and 7 seconds. By comparison, the fastest marathon ever run was 2 hours, 4 minutes and 26 seconds.

So the fastest any human’s ever run is over 27 miles per hour, and that’s impressive! But I’ll be even more impressed when someone sustains a speed of 13.12 miles per hour for the distance of a marathon, and runs it in under two hours. Hey, it could happen! If I model it mathematically, here’s what I get:

So, what do you think? Will we ever get up to 13.12 on that graph? That’s a marathon in under 2 hours. My fitting algorithms say yes, and within my lifetime (by about 2040-2050). Someone else’s analysis says that the men’s world record in the 100 meters will eventually drop to 9.35 seconds! What do you think; are you impressed yet?

Boys and Girls are Equal in Math Ability Fri, 25 Jul 2008 19:37:55 +0000 ethan Oh, but don’t take my word for it. Let’s look at the evidence to see what it tells us. After all, there have been many authoritative people contending that boys are better than girls at math. Think about how that could be possible. Could the mathematical ability of the human brain somehow be connected to the presence or absence of item 19 below?

Or, is it possible, that despite our physical gender differences, our brains’ mathematical potentials have negligible differences between them due to gender?

Previous studies (admittedly done 20 years ago) showed that boys scored higher on math standardized tests than girls did. Some argued that this proves the kindergarten insult, “Boys are better than girls!” Others argued that this was due to the fact that boys took greater numbers of advanced math and science classes in school, better preparing them to do well on the tests.

Well, it’s been 16 years since Mattel pulled the talking Barbie that said, “Math class is tough!” And despite the discouragement of ignorant educators and a society that may actually believe that girls aren’t as good at math as boys, modern girls now take just as many advanced math and science courses (except for high school physics; get working on that!) as boys do. This means that we can now test who was right: are boys better than girls at math, or were boys doing better because they were taking more advanced classes? How do we find out?

Well, let’s get the results of the study, led by Janet Hyde from my former employer, the University of Wisconsin at Madison. This study is based on the test results of 7 million students from 10 states:

The researchers looked at the average of the test scores of all students, the performance of the most gifted children and the ability to solve complex math problems. They found, in every category, that girls did as well as boys. (To their dismay, the researchers found that the tests in the 10 states did not include a single question requiring complex problem-solving, forcing them to use a national assessment test for that portion of their research.)

Wait a minute, the skeptic in you might say. Don’t boys still do better on the math section of the SATs? Ah, but their research has you covered there, too. Observe:

The study also analyzed the gender gap on the math section of the SAT. Rather than proving boys’ superior talent for math, the study found, the difference is probably attributable to a skewed pool of test takers. The SAT is taken primarily by seniors bound for college, and since more girls than boys go to college, about 100,000 more girls than boys take the test, including lower-achieving girls who bring down the girls’ average score.

On the ACT, another college entrance test, the study said, the gender gap in math scores disappeared in Colorado and Illinois after the states began requiring all students to take the test.

Hmm. So let’s sum up. Boys and girls exhibit equal math performances. They perform equally on math exams when they’ve had equal schooling, and when the same pools of boys and girls are chosen. To conclude, based on the evidence, it seems that they have the same aptitude and ability for mathematics and mathematically intensive careers.

Or, to put it more prosaically, in your face, sexism! And while I have your attention, check out this week’s Carnival of Space, where you can learn about the fact that days weren’t always 24 hours.