Alibris Secondhand Books Standard

Thursday, December 31, 2009

color changing card trick

Here's a cool card trick to end the year, with a surprise twist at the end:

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Wednesday, December 30, 2009

john graham-cumming analyzes climate data

Mathematician and programmer John Graham-Cumming has taken a look at the climate data compiled by the Met Office, the UK’s National Weather Service.

He has reconstructed the temperature trends since 1850, found an error in the Met Office's data, examined the "very artificial correction" to tree-ring data, mapped a grid of global temperature data, and produced an explanatory video:

All in all, it's a very thorough and informative analysis.

Here are the papers referenced in his video and blogs (PDF files):

Uncertainty estimates in regional and global observed temperature changes

Hemispheric and Large-Scale Surface Air Temperature Variations

Trees tell of past climates: but are they speaking less clearly today?

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Monday, December 21, 2009

buy where you shop

Tim O'Reilly consideres the shortsightedness of new online comparison shopping tools:

On the surface, these are great tools for consumers (and there are other applications besides price comparison.) But remember, cutthroat pursuit of the lowest price will hasten the demise of many retailers, while strengthening others (usually, the biggest and most efficient, who can make money on the slenderest margins.)

Sure, you might be able to save money buying online. But if you like to see the product in the store first, it's in your interest to keep the store in business:

Online shopping is terrific: you can get detailed product information, recommendations from other customers, make a choice, and have the product delivered right to your door. But if you aren't satisfied with the online shopping experience, you want to look at the physical product, for example browsing through a book in the store, you owe it to the retailer--and to yourself--to buy it there, rather than going home and saving a few dollars by ordering it online.

Think about it for a minute: the retailer pays rent, orders and stocks the product, pays salespeople. You take advantage of all those services, and then give your money to someone else who can give you a better price because they don't incur the cost of those services you just used. Not only is this unfair; it's short-sighted, because it will only be so long before that retailer closes his or her doors, and you can no longer make use of those services you enjoy.

What does the future hold? Will brick and mortar stores all eventually shut their doors? Will all consumer products someday be bought online?


Saturday, December 12, 2009

animated optical illusions



comment policy

I've never formally articulated my comment policy, but a few recent comments have made it clear to me that I need to outline what type of comments I will not accept.

No, I'm not referring to the ongoing debate in Where's the Climate Data? Disagreement — even sharp disagreement — is fine.

I'm talking about the commercial spam. If you leave an advertisement as a comment, it will be deleted.

When I started this blog, I allowed all comments. Then I started getting spam, and I deleted them as they came up. After a few weeks of this I added CAPTCHA to filter out the spambots.

On September 6, 2007, someone broke the CAPTCHA and left more than two dozen advertisments for World of Warcraft Gold. In response I silently changed the comment policy.

I now no longer use CAPTCHA. Posts fewer than 14 days old I monitor regularly. I have deleted and will continue to delete any commercial comments found on new posts. All comments on posts more than 14 days old will be sent to me first for moderation.

When you drop by to say "...please where can I buy a unicorn?" your comment is innocuous enough to be approved. But when you return the next day to post an advertisement for cialis, you'll have no such luck. So whoever is doing that, please stop.

That is all.

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Tuesday, December 08, 2009

the problem with the new atheists

Since 9/11, several atheists — most prominently Richard Dawkins, Christopher Hitchens, Sam Harris, and Daniel Dennett — have stepped up their criticism of religious beliefs. To these "New Atheists", religious moderates are as bad as religious extremists:

Here's Dawkins:

However, the moderate, sensible religious people you've cited make the world safe for the extremists by bringing up children -- sometimes even indoctrinating children -- to believe that faith trumps everything and by influencing society to respect faith.

And Harris:

However, religious moderates are themselves the bearers of a terrible dogma: they imagine that the path to peace will be paved once each of us has learned to respect the unjustified beliefs of others.

They are completely wrong, of course. Dawkins and Harris have absolutely no idea what religious moderates teach our kids. Questioning is an important part of learning, and faith-learning is no exception. If we have a healthy faith, we can question our own beliefs; and we'll be very skeptical of the crazy views of extremists.

Ironically, Robert Wright suggests in Foreign Policy magazine that the New Atheists are the ones inadvertently lending support to the extremists:

If you're a Midwestern American, fighting to keep Darwin in the public schools and intelligent design out, the case you make to conservative Christians is that teaching evolution won't turn their children into atheists. So the last thing you need is for the world's most famous teacher of evolution, Richard Dawkins, to be among the world's most zealously proselytizing atheists. These atmospherics only empower your enemies.

So too with foreign policy: Making "Western" synonymous with "aggressively atheist" isn't a recipe for quelling anti-Western Islamist radicalism.

Now Wright may be wrong. It may not be the case that extremists are benefitting from the campaigns of the New Atheists. But Wright does bring an important perspective to the table.

The New Atheists tend to speak in the world of abstracts, where all problems can be solved by simply not teaching kids about religion. Unfortunately, the real world has very concrete problems that require much greater cooperation among people who may not share the same viewpoints about things that cannot be objectively understood.

Living in Kansas, I have watched creationism rear its ugly head more than once in statewide politics. If religious moderates and non-religious people can't band together to put this monster down, Kansas students will be doomed to substandard education. That's a much more serious problem than trying to figure out exactly who is friendlier toward extremists.

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Tuesday, December 01, 2009

where's the climate data?

In a late comment to my September post titled Has the World's Climate Date Really Gone Missing? William Shields asserts:

Well, this all looks very different in light of the released emails from CRU that show deliberate moves to block FoIA requests and then delete relevant data, which is actually a crime.

The problem with this allegation is the same weakness found in the original tabloid-style articles from the Register and the National Review which prompted that post. The Climate Research Unit (CRU) is not, and never has been, the world's sole repository of climate information. Furthermore, CRU is not the source of the raw data in question, and is not under any obligation to store this data.

Fortunately for us all, the helpful climatologists at RealClimate are busy gathering links to the many online sources of climate data. Whether you're looking for raw data, processed data, paleo-data, models, reconstructions, or analysis, they can help you find it.

But I wouldn't be surprised if the climate deniers ignore the data and focus on the stolen emails. Raw data is useful for science, but informal exchanges stripped from their original context make better conspiracy theories.

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