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Even a good data display can sometimes be improved

When I first saw this graphic, I thought “boy, that’s great, sometimes the graphic practically makes itself.” Normally it’s hard to use lots of different colors to differentiate items of interest, because there’s usually not an intuitive mapping between color and item (e.g. for countries, or states, or whatever). But the colors of crayons, what […]

Censoring on one end, “outliers” on the other, what can we do with the middle?

This post was written by Phil. A medical company is testing a cancer drug. They get a 16 genetically identical (or nearly identical) rats that all have the same kind of tumor, give 8 of them the drug and leave 8 untreated…or maybe they give them a placebo, I don’t know; is there a placebo […]

How the ignorant idiots win, explained. Maybe.

According to a New York Times article, cognitive scientists Hugo Mercier and Dan Sperber have a new theory about rational argument: humans didn’t develop it in order to learn about the world, we developed it in order to win arguments with other people. “It was a purely social phenomenon. It evolved to help us convince […]

Improvement of 5 MPG: how many more auto deaths?

This entry was posted by Phil Price. A colleague is looking at data on car (and SUV and light truck) collisions and casualties. He’s interested in causal relationships. For instance, suppose car manufacturers try to improve gas mileage without decreasing acceleration. The most likely way they will do that is to make cars lighter. But […]

Worst statistical graphic I have seen this year

This gets my vote for the worst statistical graphic I (Phil) have seen this year. If you’ve got a worse one, put a link in the comments. “Credit” for this one goes to “Peter and Maria Hoey (Source: Tommy McCall/Environmental Law Institute).”

Do you have any idea what you’re talking about?

We all have opinions about the federal budget and how it should be spent. Infrequently, those opinions are informed by some knowledge about where the money actually goes. It turns out that most people don’t have a clue. What about you? Here, take this poll/quiz and then compare your answers to (1) what other people said, in a CNN poll that asked about these same items and (2) compare your answers to the real answers.

Quiz is below the fold.

Graphical insights into the safety of cycling.

This article by Thomas Crag, at Copenhagenize, is marred by reliance on old data, but it’s so full of informative graphical displays — most of them not made by the author, I think — that it’s hard to pick just one. But here ya go. This figure shows fatalities (among cyclists) versus distance cycled, with […]

“If it saves the life of a single child…” and other nonsense

This post is by Phil Price. An Oregon legislator, Mitch Greenlick, has proposed to make it illegal in Oregon to carry a child under six years old on one’s bike (including in a child seat) or in a bike trailer. The guy says “”We’ve just done a study showing that 30 percent of riders biking […]

News coverage of statistical issues…how did I do?

This post is by Phil Price. A reporter once told me that the worst-kept secret of journalism is that every story has errors. And it’s true that just about every time I know about something first-hand, the news stories about it have some mistakes. Reporters aren’t subject-matter experts, they have limited time, and they generally […]

“Tied for Warmest Year On Record”

The National Climatic Data Center has tentatively announced that 2010 is, get this, “tied” for warmest on record. Presumably they mean it’s tied to the precision that they quote (1.12 F above the 20th-century average). The uncertainty in the measurements, as well as some fuzziness about exactly what is being measured (how much of the […]

Reinventing the wheel, only more so.

Posted by Phil Price: A blogger (can’t find his name anywhere on his blog) points to an article in the medical literature in 1994 that is…well, it’s shocking, is what it is. This is from the abstract: In Tai’s Model, the total area under a curve is computed by dividing the area under the curve […]

Consulting: how do you figure out what to charge?

I’m a physicist by training, statistical data analyst by trade. Although some of my work is pretty standard statistical analysis, more often I work somewhere in a gray area that includes physics, engineering, and statistics. I have very little formal statistics training but I do study in an academic-like way to learn techniques from the […]

Works almost as well, costs a lot less

No matter how famous you are, billions of people have never heard of you.

I was recently speaking with a member of the U.S. House of Representatives, a Californian in a tight race this year. I mentioned the prediction for him, and he said “ What’s that?”

Some things are just really hard to believe: more on choosing your facts.

Republicans are much more likely than Democrats to think that Barack Obama is a Muslim and was born in Kenya. But why? People choose to be Republicans or Democrats because they prefer the policy or ideology of one party or another, and it’s not obvious that there should be any connection whatsoever between those factors and their judgment of a factual matter such as Obama’s religion or country of birth.

In fact, people on opposite sides of many issues, such as gay marriage, immigration policy, global warming, and continued U.S. presence in Iraq, tend to disagree, often by a huge amount, on factual matters such as whether the children of gay couples have more psychological problems than the children of straight couples, what are the economic impacts of illegal immigration, what is the effect of doubling carbon dioxide in the atmosphere, and so on.

Of course, it makes sense that people with different judgment of the facts would have different views on policies: if you think carbon dioxide doesn’t cause substantial global warming, you’ll be on the opposite side of the global warming debate from someone who thinks it does. But often the causality runs the other way: instead of choosing a policy that matches the facts, people choose to believe the facts that back up their values-driven policies. The issue about Obama’s birth country is an extreme example: it’s clear that people did not first decide whether Obama was born in the U.S., and then decide whether to vote Republican or Democratic. They are choosing their fact based on their values, not the other way around. Perhaps it is helpful to think of people as having an inappropriate prior distribution that makes them more likely to believe things that are aligned with their desires.

John McPhee, the Anti-Malcolm

This blog is threatening to turn into Statistical Modeling, Causal Inference, Social Science, and Literature Criticism, but I’m just going to go with the conversational flow, so here’s another post about an essayist.

I’m not a big fan of Janet Malcolm’s essays — and I don’t mean I don’t like her attitude or her pro-murderer attitude, I mean I don’t like them all that much as writing. They’re fine, I read them, they don’t bore me, but I certainly don’t think she’s “our” best essayist. But that’s not a debate I want to have right now, and if I did I’m quite sure most of you wouldn’t want to read it anyway. So instead, I’ll just say something about John McPhee.

As all right-thinking people agree, in McPhee’s long career he has written two kinds of books: good, short books, and bad, long books. (He has also written many New Yorker essays, and perhaps other essays for other magazines too; most of these are good, although I haven’t seen any really good recent work from him, and some of it has been really bad, by his standards). But…

Climate Change News

I. State of the Climate report The National Oceanic and Atmospheric Administration recently released their “State of the Climate Report” for 2009. The report has chapters discussing global climate (temperatures, water vapor, cloudiness, alpine glaciers,…); oceans (ocean heat content, sea level, sea surface temperatures, etc.); the arctic (sea ice extent, permafrost, vegetation, and so on); […]

Nebraska never looked so appealing: anatomy of a zombie attack. Oops, I mean a recession.

One can quibble about the best way to display county-level unemployment data on a map, since a small, populous county gets much less visual weight than a large, sparsely populated one. Even so, I think we can agree that this animated map by LaToya Egwuekwe is pretty cool. It says it shows the unemployment rate […]

Unhappy with improvement by a factor of 10^29

I have an optimization problem: I have a complicated physical model that predicts energy and thermal behavior of a building, given the values of a slew of parameters, such as insulation effectiveness, window transmissivity, etc. I’m trying to find the parameter set that best fits several weeks of thermal and energy use data from the […]

Creating a good wager based on probability estimates

Suppose you and I agree on a probability estimate…perhaps we both agree there is a 2/3 chance Spain will beat Netherlands in tomorrow’s World Cup. In this case, we could agree on a wager: if Spain beats Netherlands, I pay you $x. If Netherlands beats Spain, you pay me $2x. It is easy to see […]