Monthly Archives: October 2009

Are You A Real Scientist? Find Out Now!

(click for a larger view)

RealScientistFlow

This chart is my social commentary on the strange attack on Stephen Dubner and Steven Levitt’s new SuperFreakonomicsbook. It seems a large chunk of people are worked up over a chapter in the book in which they look into alternate, controversial ways of solving the climate-change/global-warming/whatever-the-kids-are-calling-it-these-days problem.

At the eye of the storm are people accusing Dubner and Levitt of lies and misrepresentation in their book, particularly as it relates to their conversations with Ken Caldeira, a respected climate scientist working with Intellectual Ventures (possibly the most arrogantly named company ever).

Long story short: A blogger at Climate Progress claimed that Caldeira objected to his portrayal in the book and that Dubner and Levitt essentially flipped him off and left burning dog crap on his porch. Dubner responded that Caldeira read through two drafts of the chapter, correcting things he felt were wrong. Caldeira feels the authors worked in good faith and, while he may or may not agree with their conclusions, he feels their portrayal was fair.

What I find funny about the whole thing is the extent to which most people are blasting Dubner and Levitt even though they have explained repeatedly that they are not challenging the scientific status quo concerning climate change, that their reference to global cooling is a reference to finding ways to use technology to reverse global warming, which they unabashedly believe is happening. Their chapter looks at people working to solve the problem (you know, the problem of global warming which they believe is happening) who are working outside the “climate-change establishment”.

On a related note, Dubner has announced that he will change his name to Stephen Dubner-Yes-I-Believe-Climate-Change-Is-A-Problem.

But for the blasting of Dubner and Levitt and the (unconvincing, in my opinion) Brad DeLong’s “you should have let me write your book” post, no one can really give me a good reason to believe that they have a better grasp on the topic than Dubner and Levitt.

(Update: Greg Mankiw gives me reason to believe that Yoram Bauman has a better grasp on the topic and he seems disappointed. However, his back and forth with Steve Levitt amounted to “You may be technically right on the specifics, but the gist you gave was inaccurate.” I’m still struggling to try and reconcile that with the statements attributed to Ken Caldeira who, you may recall, previewed multiple drafts of the chapter. If he really did OK the overall scientific gist of the chapter, that strikes me as a pretty powerful authority.)

Up till now, I’ve stayed out of the climate change arena because I don’t have anything resembling an appropriate background for dealing with the topic. But the problem I’ve found is that people on both sides of the argument don’t really give a crap about credentials or scientific rigor.

What they care about is simply “Did this guy end up on my side of the argument?” If he did, he is a real honest to goodness scientist. If he didn’t, he is a hack, a washed up old know-nothing, a dishonest tool for religious environmentalism or a shill for the oil companies (depending on which side you’re on).

The reason I’m skewering the pro-climate-change side in this visual is because they seem to be much narrower in their orthodoxy. I’ve known extremely liberal people with graduate degrees in nuclear physics who get angry because no one wants to hear their solution to climate change (hint: it rhymes with buclear flower pants) due to the fact that the movement (from a political stand point) is dominated by long time environmentalists who spent their formative years fighting against nuclear power and don’t want to admit that they might have gotten that one wrong. (How is that for a run-on sentence?)

The “climate skeptics” side is often just as scientifically lackadaisical, but they’ll welcome anyone with open arms as long as they’re even remotely skeptical of any part of the political climate change agenda. They’ll accept anything including “climate change isn’t happening”, “man isn’t causing climate change”, “climate change isn’t a problem”, or (my favorite) “the solution isn’t (Kyoto/carbon tax/ethanol/hybrid car/whatever-my-political-enemies-like), the real solution is (fill-in-the-blanks-with-something-that-will-make-my-political-enemies-angry)”.

But, ultimately, I find the pro side to be more humorous because it is populated by approximately 30 actual scientists with knowledge in the field and millions of people with no scientific knowledge in the field who just like to feel smug about being all “scientific” while bashing other people who aren’t “scientific”.

And how do they determine who falls into which category? See the chart above.

Jumping Into Visualization Without the Math

I found this link from Instapundit, so credit where it is due.

You may have seen this visual of job loss across the country. It maps the job gains and losses in major metro areas across the country and, on the surface it seems pretty cool. Here’s October 2008.

JobLossOctober2008

As someone who really loves information visualization, I applaud the effort. But it’s wrong.

Let’s take a quick look at the legend. See if you can spot the problem.

JobLossScale

Keen readers will notice the problem… whoever created this visual scaled only the diameter of the circle. The problem with this is what we can see below.

JobLossScaleProblem

Here I took the “10,000” circle and duplicated it over 50 times within the “100,000” circle. If this visual were an accurate one, we would multiply the 10,000 circle ten times to get 100,000. That’s just the way these things should work.

Math Time! (skip if you don’t care)

The area of a circle is calculated with the equation:

AreaText

Which means that when they increase the height of the circle by 10, they increase it’s area by 100. This means that instead of the numbers increasing the way they should, the small numbers end up looking REALLY small and the big ones look absurdly huge.

End of Math Time

I’m not trying to be an a**hole here. The idea behind the visual was a good one. But these things really do need to be accurate. Most people don’t know how to tell when a visual is in error and they end up with an incorrect impression from a poorly built infographic.

Space Junk And Visual Lies

A little while back, due to a collision between a dead Russian military satellite and a US commercial satellite, there was some noise about space junk because of the potential danger it posed to the International Space Stations and the Shuttle. The image that of space junk that became the icon of the problem is this image (click to enlarge):

SpaceJunkImage

I hate this image. Passionately.

The reason I hate this image is because it is probably the biggest visual lie I’ve ever seen. In his book The Visual Display of Quantitative Information, Edward Tufte has a concept called the “Lie Factor”. The “Lie Factor” judges the extent to which the data and the visual are out of sync.

Nothing could be more out of sync with reality than this image. While it imagines the appropriate number of objects circling the earth, it completely misrepresents the scale of those objects.

Space is unimaginably huge. While there are thousands of objects circling the earth, they range in size from a volleyball to a small school bus. If you do the calculations, the objects in this image range in size from Delaware to Tennessee.

Math Time! (skip if you don’t care)

In this image the diameter of the earth is about 1950 pixels. The real diameter of the earth is about 8000 miles. That means that every pixel is a shade over 4 miles.

The smallest piece of space junk in this image is about 10 pixels wide and 18 pixels tall and the largest one is about 24 pixels wide and 104 pixels tall. That gives the small objects an area of about 3000 square miles (about 30% larger than Delaware) and the large ones an area of 41,000 square miles (a shade smaller than Tennessee).

End of Math Time

To give an example of this exaggeration, let’s look at Angelina Jolie. (How’s that for a non sequitur?) Jolie has a freckle (beauty mark, mole, whatever) above her right eye.

JolieFreckle

Let’s say we’re concerned about people getting skin cancer, so we want to make a shocking graphic that we hope will help people remember to monitor skin markings for signs of melanoma. If we lied visually as much as the space junk photo, we would change a picture of Angelina Jolie from:

JolieNormal

to

JolieFreckleExaggerated

Imagine the Photoshop is done a shade better than I can do. The intention to do good and get people to realize the severity of melanoma is all well and good, but it doesn’t justify lying to people.

Granted, the space junk image holds the disclaimer that it is “an artists impression”. But that isn’t how people read these kinds of things and anyone who believes otherwise is, quite frankly, lying to themselves about the realities of human perception and belief. People see these images and they expect that they match reality in some way. Do a search for “space junk” to find out how many otherwise intelligent people have accepted this image as reality without a breath to admit how inaccurate it is.

This is not to say space junk isn’t a problem. I would have “solved” the problem of visual representation by portraying the space junk as a dot. A single pixel that can clearly indicate position instead of pretending to be a representation of size. Then, I would explain that, even though these objects are very tiny compared to the size of the space they’re in, this junk moves at thousands of miles an hour… making very small objects insanely dangerous.

You could effectively compare it to shooting a bullet into the air. A tiny piece of metal in a huge space can be really dangerous. People get that. There is no reason to portray the bullet as a 747.

I’m worried that even scientific people either didn’t recognize this problem or didn’t feel the need to speak up about it. Even people experienced in infographics didn’t say anything (see here, and here). (Side Note: I take particular pleasure is smacking down Wired magazine for putting up this graphic without even mentioning that it is an “artist rendering”. As a whole, they tend to be smug and irritating in the extent to which they dismiss anyone without technical or scientific expertise. Here they reveal that they are just as susceptible to junk science as the average Joe.)

There is an extent to which many people in scientific and technical journalism are content to give people the appropriate impression (“Space junk is a dangerous problem”) without providing them with the appropriate information. Or, to put the problem simply, they think the end justifies the means.

I take the view that truth in data is the highest importance. I’m frustrated in how lonely it is out here on my high ground.

What The September Unemployment Rate Tells Us (Or, How I Learned To Start Worrying and Hate the BLS Data)

Latest unemployment data has come out and the people who were claiming “ah, but job losses are slowing” were smacked down and sent to the corner to think about what they’ve done.

The unemployment rate was up .1%, from 9.7% to 9.8%. That’s not so bad, right?

To speak frankly, the unemployment rate tells so little of the story at this point that it’s hardly a useful metric. If you’re looking for a useful metric, start looking at the raw unemployment numbers.

The problem with the unemployment rate is that it doesn’t compare the employed with the unemployed. Instead, it compares people who are employed with those who don’t have jobs, but have looked for a job in the last 4 weeks”. This make a certain kind of sense; we don’t want to count stay-at-home dads or retired individuals as unemployed.

However, this means that an exodus from the workforce could mask the severity of the job situation. To illustrate, I’ve created a visual:

20peopleEmployed

Let’s say we have 20 people in the workforce and 2 of them fit the technical definition for unemployed, which means that they’re actively looking for work. That gives us an unemployment rate of 10%.

20pepopleWithX

Now, let’s say one of the unemployed people got tired of being unemployed and decided to go back to school. She has now removed herself from the labor force, so we don’t count her when we count unemployed people. Let’s also say that one of the employed people lost his job and instead of looking for a new one, he decided to simply retire.

18peopleEmployed

As you can see we haven’t added any jobs… in fact we have fewer jobs than we did before. But we took a higher percentage of people out of the “unemployed” group than we did out of the “employed” group. It’s now 1 person unemployed and 17 people employed. We’ve “slashed” the unemployment rate to 5.5%.

This current job report is actually a perfect example of this. We lost 785,000 jobs this past month. That makes it the biggest month of job losses since March. But the number of people in the unemployed group rose only 214,000. This is because  we saw over twice that number simply leave the work force altogether.

If we took employment numbers for this month compared it to the labor force for last month, we would have an unemployment rate of 10.2%… almost a half a percent higher than the one we have!

I try to be an optimist, but it is hard to see this report as anything but a disaster. Furthermore, we are so far into the implementation of the stimulus, that I have a hard time seeing it as anything but a huge failure. I understand that only about 10% of the stimulus has actually been spent, but part of the point of the stimulus was to get money out into the economy in order to inject a little cash flow into the situation. That means that a huge part of the success of the stimulus relied on getting the money out in a timely manner.

I know that defenders of stimulus theory would object that it takes time to spend $800 billion and that you can’t spend that much very quickly without massive fraud. To which I reply: “Well, duh.” I think that’s a great argument against the stimulus and I wish they had brought that up back in February and March instead of bashing people like me for bringing that up back in February and March.

Back to the point, we have seen job growth in only one month out of the last 17. We need to stop focusing on the unemployment rate and start looking at raw jobs data. Only when we see the raw number of jobs start rising consistently can we be confident of economic recovery.

Note: To be fair, jobs tend to be a lagging indicator, but outside the stock market increases, I’m seeing little reason to be optimistic. And, quite honestly, the stock market seems to be very excited about absolutely nothing. It’s like they’re throwing a champagne party because the world hasn’t ended, neglecting the fact that it is still on fire.