Chart shows how much radiation you would absorb from various sources

This chart from XKCD shows the ionizing radiation you might absorb from various sources according to the standard sievert (Sv) measurement unit.

The interesting thing about this chart is it allows you to compare radiation absorption of a wide range of activities from the smallest risk, sleeping next to another person (tiny risk); to something greater but not really that bad in the end, such as being 50 km away from the Fukushima site in Japan; to something catastrophic, like being next to the Chernobyl reactor core after its explosion and meltdown. The chart helps you to understand where a fatal radiation dose stands within that great range.

XKCD gives a disclaimer that the chart probably contains mistakes and warns that “if you’re basing radiation safety procedures on an internet PNG image and things go wrong, you have no one to blame but yourself.”

The following image is linked from the original — click on it to inspect the original at full size.

XKCD's radiation does chart

 

AB — 19 March 2011

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Why People Don’t Believe Scientists Even When There Is ‘Consensus’

An interesting study, soon to appear in the Journal of Risk Research, by Yale law professor Dan M. Kahan and colleagues, suggests that people tend to disbelieve scientists whose cultural values are different than theirs.

I’m not able to determine when this study will be published, but you can find an abstract at this link, and I was able to download a preliminary version of the whole article in PDF by clicking on the link on that page that says “One-Click Download.”

These conclusions shed light on the debate over anthropogenic climate change, Kahan tells Science Daily (“Why ‘Scientific Consensus’ Fails to Persuade“):

We know from previous research that people with individualistic values, who have a strong attachment to commerce and industry, tend to be skeptical of claimed environmental risks, while people with egalitarian values, who resent economic inequality, tend to believe that commerce and industry harms the environment.

(For more on the climate-change controversy, see my previous entry, “John Abraham’s Point-by-Point Rebuttal of Climate-Skeptic Monckton.”

Kahan and colleagues based their study on the theory of the cultural cognition of risk. In his paper, Kahan says this theory “posits a collection of psychological mechanisms that dispose individuals selectively to credit or dismiss evidence of risk in patterns that fit values they share with others.”

The researchers surveyed a representative sample of 1,500 U.S. adults. They divided this sample into groups with opposite cultural worldviews, some favoring hierarchy and individualism, the others favoring egalitarianism and communitarianism.

They surveyed the respondents to determine their beliefs about what in fact is the scientific consensus on issues of climate change, disposal of nuclear waste, and concealed handguns, with particular focus on the associated levels of risk in each of those areas. Various statements were attributed to fictional personas portrayed as authors of books on these various issues. Respondents were asked to judge whether each author is really an expert or not.

Analysis of the results on the climate-change issue revealed that:

Disagreement was sharp among individuals identified (through median splits along both dimensions of cultural worldview) as “hierarchical individualists,” on the one hand, and “egalitarian communitarians,” on the other. Solid majorities of egalitarian communitarians perceived that most expert scientists agree that global warming is occurring (78%) and that it has an anthropogenic source (68%). In contrast, 56% of hierarchical individualists believe that scientists are divided, and another 25% (as opposed to 2% for egalitarian communitarians) that most expert scientists disagree that global temperatures are increas-ing. Likewise, a majority of hierarchical individualists, 55%, believed that most expert scientists are divided on whether humans are causing global warming, with another 32% perceiving that most expert scientists disagree with this conclusion.

The study revealed similar results around the issues of geologic isolation of nuclear wastes and concealed-carry laws.

So should we conclude that people are going to believe what they want to believe, and that’s all there is to it? The authors make an interesting statement about the implications for public presentation of scientific findings:

It is not enough to assure that scientifically sound information — including evidence of what scientists themselves believe — is widely disseminated: cultural cognition strongly motivates individuals — of all worldviews — to recognize such information as sound in a selective pattern that reinforces their cultural predispositions. To overcome this effect, communicators must attend to the cultural meaning as well as the scientific content of information.

The report suggests some ways that cultural meaning might be considered in communicating with the public. One such strategy is what the authors call narrative framing:

Individuals tend to assimilate information by fitting it to pre-existing narrative templates or schemes that invest the information with meaning. The elements of these narrative templates — the identity of the stock heroes and villains, the nature of their dramatic struggles, and the moral stakes of their engagement with one another — vary in identifiable and recurring ways across cultural groups. By crafting messages to evoke narrative templates that are culturally congenial to target audiences, risk communicators can help to assure that the content of the information they are imparting receives considered attention across diverse cultural groups.

AB — 24 Sept. 2010

John Abraham’s Point-by-Point Rebuttal of Climate-Skeptic Monckton

[Updated 16 July 2010]

Yesterday I reviewed an informative presentation by John P. Abraham, associate professor in the school of engineering of St. Thomas University in Minnesota. In his presentation, “A Scientist Replies to Christopher Monckton,” Abraham offers a point-by-point rebuttal/refutation of claims made in a presentation he attended by Christopher Monckton, in which Monckton presented arguments against anthropogenic (man-made) global warming (AGW), that is, the idea that human activity is causing an increase in global temperatures resulting in dangerous climate change.

Monckton is Chief Policy Adviser at the Science and Public Policy Institute (SPPI) and is well-known as a critic of anthropogenic global warming. (See one of Monckton’s slides referenced by Abraham, to right.)

Though long (it’s a 73-minute Flash presentation with voiceover), Abraham’s critique of Monckton is well worth reviewing, especially if you’ve been wondering about the emerging criticism of AGW and the general scientific consensus on climate change.

[Update added 16 July 2010]: A reader (see his comment below) has kindly pointed me to Monckton’s response to Abraham’s presentation. This is in PDF format and is very long — his answer is in the form of a series of questions (500 of them). See “Response to John Abraham, by Christopher Monckton.”

I have to say that, although I tend to agree with the consensus position in this case, just because most or even all of the experts in a certain field believe the same way, I don’t think others should be obligated to follow the crowd. And those who do accept the consensus point of view should be willing to keep their convictions on the table and to re-examine matters when new information becomes available.

To say that those who question claims of climate-change are “anti-science” or to call them “deniers” (as if their challenges were somehow akin to denials of the Holocaust) is disingenuous and counter-productive. It gets people arguing about all the wrong things, instead of communicating and working on problems.

In the case of the challenges to the climate-change consensus, science itself is not being called into question. The real issues have to do with things like politics, public policy, economic philosophy, and ideology. If people’s livelihoods and the well-being of their descendants are in play, isn’t it reasonable to allow them to call into question the conclusions and policy implications of those who evoke climate science as justification for their policy recommendations?

Also, it’s reasonable to point out that scientists themselves are humans with their own foibles, and while for the most part they might believe they are carrying out their work according to well-established principles and sound procedures, some of them have shown themselves to be influenced by self-interest, greed, and ideological leanings. So if their work is financed with public resources and being used to influence policy, isn’t it reasonable to expect their work – and especially their statements about its implications – to stand up to public scrutiny?

If researchers and institutions are convinced that anthropogenic global warming is a real danger, then it would behoove them to find ways to present the evidence in an accessible way, rather than just sticking their noses in the air and spouting arrogant put-downs of those that raise questions.

That brings me to the value of John P. Abraham’s presentation.

Sample slide from Abraham presentationI found Abraham’s presentation reasonable and level-headed (see one of his slides to right). He refrains from personal attacks. Abraham analyzes Monckton’s scientific references, charts, and assertions in detail. Where available, he examines the data sources for Monckton’s charts and the papers he references. He even wrote to the authors of many of the original papers to ask for clarification when needed and shows their replies in his presentation.

Abraham’s presentation is really produced as a point-by-point refutation of Monckton, but along the way you learn a lot about climate change and the associated data. Pretty easy to follow, for a non-specialist reader with a fair understanding of science.

“My goal,” he says, “is to show people how they can learn about the scientific understanding on their own.”

The questions he addresses include:

  • Has Al Gore really overestimated the future sea-level rise by 100 times, and is it really true that sea levels are not rising?
  • Are polar bears in the Canadian Beaufort Sea really endangered by warming temperatures or not?
  • Was there a medieval warming period comparable to that taking place today, and did the IPCC “erase” that medieval warming period from its historical climate data?
  • Do IPCC’s climate sensitivity estimates really rest on just 4 scientific papers, rather than 2,500?
  • Have average temperatures actually been going down, contradicting IPCC projections?
  • Is there really no evidence for any catastrophic effects of anthropogenic climate change anywhere in the world?
  • Is it really true that increase in CO2 levels is an effect of warming rather than a cause, and is it really true that CO2’s effect on global temperature is negligible?
  • Is the extent of arctic sea ice actually remaining steady rather than declining?
  • Has the Greenland ice sheet really been increasing rather than decreasing?
  • Is it really true that the Himalayan glaciers have not been retreating?
  • Is it really true that oceans are not heating up?
  • Is it really true that global warming is caused by increased solar activity, rather than human activities?

If these kinds of questions concern you, I encourage you to review Abraham’s presentation.

AB — 29 June 2010

One Reason Youtube Is a Great Resource: Khan Academy’s 1,200 Educational Videos

Many people think of YouTube as a big time-waster with nothing but videos of animals dancing and guys getting whacked in their privates.

But as time goes on, I become more and more conscious YouTube as a great resource in many respects. For example, in my work as a writer and analyst, I’ve been making good use of corporate videos on YouTube, where it’s possible now to access in-depth presentations by company executives, scientists, and other experts.

Thanks to a mention yesterday in Boing Boing, I’ve learned about Khan Academy, which now has over 1,200 educational videos on YouTube. Using a very simple “chalk talk” format, Salman Khan, an engineer and manager, provides 10-20-minute video presentations on a huge variety of topics, including science, history, math, finance, economics, and more.

These videos would be useful as quick reviews or knowledge fill-ins for students, both adult and child, or for parents who are trying to help their kids with their studies. I also find them useful as a writer who needs to be able to get up-to-speed quickly on economics and finance topics.

Khan creates his videos on a tablet computer with pen input. Here’s an example of a video explaining the basics of banking:

AB — 8 June 2010

Coming Soon: Tom Cruise’s Computer Interface From ‘Minority Report’

My favorite computer interface has to be the fictional one used by Tom Cruise in the 2002 Steven Spielberg movie Minority Report (based on a 1956 short story by Philip K. Dick). In the movie, Cruise plays a time cop who is part of a team that prevents murders by predicting them in advance and arresting the future perpetrators.

What has always fascinated me about the movie is the computer interface the cops use to do their investigations — it’s a huge holographic screen that hangs in the air in front of the user, who interacts with it using virtual-reality gloves. Here’s a screen shot from the movie that will give you an idea:

Computer interface from Minority Report

The exciting news for me comes from a TED Talks video from February 2010 showing a lecture by John Underkoffler of the MIT Tangible Media Group (“John Underkoffler points to the future of UI“), who was science advisor for Minority Report. He and colleagues designed the interfaces that appeared in the film.

Underkoffler has some fascinating things to say about how interfaces are evolving. He tells how the design work was done for Minority Report — the design for the computer interfaces was done as a real R&D project.

But most exciting is that Underkoffler and colleagues are actually developing the real thing — the “spatial operating environment” as he calls it — and he was able to demonstrate it during his talk. Here’s a still of his demo from the video:

John Underkoffler demonstrates UI

During his talk he says:

Much of what we want computers to help us with in the first place is inherently spatial, and the part that isn’t spatial can often be ‘spatialized’ to allow our wetware to make better sense of it.

A spatialized interaction model, he believes, improves our computing experience, as it aligns better with the way our brains work.

During the talk, Underkoffler demonstrates a logistics application his team is developing that combines structured data with 3D geographical mapping. He also shows how a spatial operating environment might be used for media manipulation and editing.

Very soon, Underkoffler says, “this stuff will be built into the bezel of every display, it’ll be built into architecture.”

At the end of the presentation, the host asks the big question: “When? … In your mind, five years’ time, someone can buy this as part of a standard computer interface?”

Underkoffler replies, “I think in five years’ time, when you buy a computer, you’ll get this.”

The fist “killer app” for the spatial operating environment? “At the moment, our early adopter customers — and these systems are deployed out in the real world — do all the big data-heavy, data-intensive problems with it. So, if it’s logistics in supply chain management, or natural gas and resource extraction, financial services, pharmaceuticals, bioinformatics — those are the topics right now. But that’s not the killer app!”

He leaves us hanging at that point, recognizing perhaps that the most interesting applications are impossible to foresee.

Here’s the video in its entirety, with lots of fascinating demonstration footage:

AB — 1 June 2010

Are We All on the Autism Spectrum?

Something Nassim Nicholas Taleb says in The Black Swan on page 194 raises the question whether we are all on the autism spectrum in some sense:

This mental block about the future has not yet been investigated and labeled by psychologists, but it appears to resemble autism…. Autistic people cannot put themselves in the shoes of others, cannot view the world from their standpoint…. Interestingly, autistic subjects, regardless of their “intelligence,” also exhibit an inability to comprehend uncertainty.

Just as autism is called “mind blindness,” this inability to think dynamically, to position oneself with respect to a future observer, we should call “future blindness.”

To me this raises the question whether in some respect we are all on the “autism spectrum,” but that those we diagnose as autistic are at the extreme in exhibiting a disability shared by all.

Interested in comments: Does this make sense?

Autism Spectrum

AB — 24 April 2010