Author Archive for Steve Landsburg

Bad Logic — Or Bad Arithmetic?

In a blog post on what he calls the “Bad Logic of Fiscal Austerity”, Paul Krugman lays the following calculation before the public:krugman

Let me start with the budget arithmetic, borrowing an approach from Brad DeLong. Consider the long-run budget implications for the United States of spending $1 trillion on stimulus at a time when the economy is suffering from severe unemployment.

That sounds like a lot of money. But the US Treasury can currently issue long-term inflation-protected securities at an interest rate of 1.75%. So the long-term cost of servicing an extra trillion dollars of borrowing is $17.5 billion, or around 0.13 percent of GDP.

Yes. That’s the long-term cost of borrowing an extra trillion dollars. (Actually, the cost is even lower than Krugman says it is.) But the long term cost of spending an extra trillion dollars is somewhere in the vicinity, of, oh, about a trillion dollars, or about 7.4% of GDP.

Now you might argue that if some of that spending puts unemployed resources to work, then the true cost of spending a trillion is somewhat less than a trillion, but Krugman, at least here, does not attempt to make that argument. Nor do I expect that even Paul Krugman would dare to argue that an adjustment for unemployed resources could reduce the cost of government spending by roughly 98%.

Krugman is right when he says that borrowing is cheap. But the issue isn’t borrowing; it’s spending—and spending is expensive. It appears that like the President, Krugman wants to divert your attention from spending to borrowing so he can dismiss legitimate concerns without even acknowledging them. It’s a cheap trick. Don’t let either of them get away with it.

Edited to add: In fairness to Krugman, he appears to be imagining that the trillion is never paid back, so that the cost of spending it is simply the debt service of 17.5 billion per year forever. But his column makes it sound like the cost is a single one-time payment of 17.5 billion, which is absurd.

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Riddle Me This

qA few years back, when Google acquired YouTube, I was heard to remark that the deal seemed kind of…imprudent. Given YouTube’s potential as a lawsuit generator, the best owners might not be the guys with some of the world’s deepest pockets.

A colleague points out that it seems equally odd for a company with pockets the depth of BP’s to be engaged in as risky an activity as deep water oil drilling. Why wasn’t this project sold off to someone with a lot less to lose?

Maybe BP expected to be protected by laws limiting its liability, but surely it was foreseeable that those laws might be circumvented, as it appears they’re about to be. So if that’s part of the answer, it’s only a small part.

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Weekend Roundup

roundup2The reason we have journalists is to direct our attention to both That Which Is Seen and That Which Is Unseen. The New York Times fell down on the job last week when it came to proposed regulation of the nanny market, by showing us That Which Is Seen by the New York Times while overlooking not only That Which Is Unseen but even That Which Is Seen By Everybody Without Blinders On. On Monday, we did our bit to pull the blinders off.

On Wednesday we contemplated the prospect of Betelgeuse going supernova, and asked this question: If an explosion happens, by how much will various earthbound observers disagree about its timing? Answer: If the explosion becomes visible just as you’re standing on a streetcorner while a driver runs over your toe, heading in the direction of Betelgeuse at 70 miles per hour, then you’ll say it took place 600 years ago whereas the driver will say it took place 600 years plus half an hour ago. A small amount in the scheme of things, but here at The Big Questions, we worry about the details.

(The geometry is here. To forestall confusion, the steeper red line is not the driver’s worldline; it is parallel to the driver’s worldline. His worldline crosses the vertical axis at the time when light from the explosion arrives, about 600 years above the illustrated line.)

On Thursday, we lamented the politicization of the President’s Council of Economic Advisors, which, as our commenter Uncle Maury observed, began under the first President Bush, but has been carried to new depths by the current administration. It is sad indeed that Council Chair Christy Romer allowed herself to be dragged into this muck.

And on Tuesday and Friday, we had a little light refereshment.

I’ll see you next week.

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Posted Without Comment

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Teachers and Councilors

S030409JB-0043.JPGThe White House has dispatched Christy Romer, a distinguished economist and chair of the President’s Council of Economic Advisors, to rustle up support for emergency spending to keep teachers employed. Her piece in the Washington Post is remarkable for a complete absence of arguments in favor of spending this money on teachers as opposed to say, plumbers or cab drivers or pharmaceutical researchers or computer programmers or minor league ballplayers. (See for yourself.)

So why the singular focus on teachers? The answer, of course, is that unlike plumbers or cab drivers or pharmaceutical workers or computer programmers, teachers, through their unions, were major contributors to the Obama campaign.

All victorious politicians engage in the unsavory practice of diverting spoils to their most vigorous supporters at everyone else’s expense. In this, the current administration may be no more blameworthy than any other. But I’m pretty sure that sending out the chair of the Council of Economic Advisors to defend these political payoffs marks a new sort of low. Traditionally, the Council is composed of first-rate academics whose job is to give good counsel and remain above the political fray. Shame on the President for debasing that noble mission, and shame on Christy Romer for going along with it.

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Beetlejuiced

I’m not pompous; I’m pedantic.
There’s a difference.
The Calligraphic Button Catalogue

Just about a year ago, a team of scientists reported that Betelgeuse—the bright red star in Orion’s shoulder—appears to have shrunk by about 15% since 1993. That would mean the diameter’s been shrinking at about 1200 miles an hour for all that time.

Such shrinkage—if it’s really happening (it’s hard to be sure)—could be the precursor to a supernova explosion, which would be way cool. The mathematician John Baez computes that a supernova Betelgeuse might be roughly as bright as the full moon, or maybe up to three times as bright.

Surprisingly, it took almost a year for this information to be widely reported on the Internet, but in the past few weeks, a number of sites have cropped up touting the upcoming supernova, and, as you might expect, a few prophecying doom. You can ignore the doomsayers; at a distance of 600 light years, Betelgeuse is too far away to hurt us.

Browsing the various science forums (such as Discover‘s), I’m struck by how often the following simple question comes up: Given that Betelgeuse is 600 light years away, is it or is it not true that it would it would take 600 years for us to notice any explosion? Or to put this another way: If the sky lights up with a new moonlike object tomorrow night, does that mean the explosion took place 600 years ago?

A pretty good answer—and the one that’s being given on all those science forums—is “yes”. But that can’t be exactly right, at least not for all of us, because at any given moment some of us are sitting in our living rooms while others are driving on the Interstates. Relativity tells us that if we’re moving relative to each other, then we must disagree about the times of distant events.

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The Star of the Phillipines

One year ago today, somewhere in the Phillipines, a reporter checked his web logs and wondered where all the new readers were coming from. Today we celebrate the first anniversary of one of the most unfortunately worded headlines in the history of journalism.

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Nanny Nanny Boo Boo

I guess this is why I never got that call from the New York Times.

To be a Times contributor, you apparently have to write like Mara Gay, who penned these lines for a front page article last week:

New York may soon become the first state to offer employment protection for nannies.

The state Senate passed a bill of rights for domestic workers this week, a measure that would require employers to offer New York’s approximately 200,000 household workers paid holidays, overtime pay and sick days.

Supporters say the step will provide needed relief to thousands of women — and some men — who are helping to raise the children of wealthier New Yorkers without any legal workplace rights beyond the federal minimum wage.

Now, you see, if I had been writing this article, it might have opened more like this:

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Weekend Roundup

I jumped the gun on Tuesday, celebrating Frederic Bastiat’s birthday about a month early. Fortunately, our commenter Cloudesly Shovell saved me from embarrassment by noting that Bastiat is well worth an entire month of celebration.

On Wednesday, we had some biting words about math education from my colleague Ralph Raimi, whose web page I continue to recommend for amusement and edification.

And on Thursday and Friday, we took on current events, lamenting the President’s misleading suggestion that tax increases can be a cure, or even a palliative, for excessive spending, and lamenting the general lack of perspective that leads to more gnashing of teeth over a $10 billion oil spill than a $300 deadweight loss due to taxation.

Several commentators noted that with this last post, we’d come full circle right back to Bastiat, author of timeless That Which is Seen and That Which is Not Seen. In the words of commenter Seth, “A duck caked in oil is seen. The deadweight loss is unseen.” (ScottN and others made the same point.) Yes, that’s probably the explanation. How sad that after 200 years, Bastiat’s lesson (that the unseen is as important as the seen) has yet to sink in.

See you Monday.

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What’s Worse Than An Oil Spill?

Let’s try for a little perspective. The BP oil spill threatens to cause something like $10 billion worth of damage. That’s pretty bad. By contrast, an extra trillion dollars worth of federal spending threatens to cause something like $300 billion worth of deadweight loss (that is, underproduction due to tax avoidance and disincentives to work). That’s 30 times worse. How is it that so much angst about the former seems to be coming from people with a history of shrugging their shoulders at the latter?

Both $10 billion and $300 billion are extremely rough guesses, but the $300 billion figure comes from the widely cited estimates of Harvard’s Martin Feldstein, according to which a one dollar tax increase triggers about 30 cents in deadweight losses. Since a trillion in new spending means a trillion in new taxes (either now or in the future), we get $300 billion in deadweight loss.

Of course $10 billion worth of oil-related damage is still big enough to be worth a goodly dollop of angst. But keep these things in mind:

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Maple Tree Economics

mapleIn his speech at Carnegie-Mellon yesterday, the President lamented the growth of federal spending and proposed to attack the problem partly by letting the Bush tax cuts expire. Can you say non sequitur, boys and girls?

Now as it happens, I’ve got this maple tree in my yard that’s been growing much too fast for my tastes. In fact, it’s been growing far faster than I have. But inspired by the president, I’ve found a solution. I’m going to stock up on E.L. Fudge Double Stuf cookies so I can grow faster than the maple.

The President raises the real problem of excessive spending so that he can misdirect your attention to the phony “problem” of excessive government debt—that is, an excessive gap between spending and tax revenues. This is very like my raising the real problem of my overlarge maple tree in order to misdirect your attention to the phony “problem” of an excessive gap between the height of the maple and the size of my waistline—giving both me and the President equally flimsy excuses to do exactly what we wanted to do in any case, namely gorge out on junk food or let taxes rise.

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Making Math Palatable

My colleague Ralph Raimi is witty, acerbic and wise about many things, but particularly about mathematics education. A little time spent browsing around his web page will reap ample rewards in the form of both entertainment and edification. Today I’d like to share a little passage he sent me by email:

I have never tried to count the times I have read a newspaper article explaining that students are bored with math that has no visible practical application, and follows with an example of a teacher, or club, that rectifies the situation in some novel and engaging way.

In the present case a class has built a sculpture that resembles a graph of a modulated wave motion. Of all the practical, real-world
applications of mathematics! It is as practical as a snowman.

Why doesn’t anyone ask for real-world applications of table tennis? What a bore any game must be, that has no real-world application! Why do kids stand for it? Ping-pong again? Ugh.

But I can think of something: Let’s all make a model of a ping-pong ball in the school yard, seventy feet high, blocking all the entrances and thus preventing all us students from entering the (ugh) school. Then we can take our fishing poles and torn straw hats out from under our beds and, with the hats on our heads and fishing poles over our shoulders, all traipse together down the dusty road to Norman Rockwell’s house.

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Frederic Bastiat

bastiat.smallToday is the 209th birthday of Frederic Bastiat, the patron saint of economic communicators.

Of all the essays ever written, the one I most wish every voter could read and understand is Bastiat’s That Which is Seen and That Which is Not Seen. A boy breaks a window. Someone in the crowd observes that it’s all for the best—if windows weren’t occasionally broken, then glaziers would starve. This can’t be right, says Bastiat. If it were, we’d have no reason to diapprove of a glazier who pays boys to break windows. But why is it wrong? It’s wrong because it focuses on what is seen—six francs in the glazier’s pocket—and ignores what is unseen, namely the shoemaker who is deprived of a sale because those six francs come from what would have been the homeowner’s shoe budget.

Bastiat’s great insight in this essay is that exactly the same fallacy, in only slightly subtler form, underlies many of the public policy positions that were taken seriously in the 19th century—and, we might add, in the 21st.

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Weekend Roundup

Following three (count ’em: one, two, three) spirited discussions of the 1964 Civil Rights Act, one exploration of the perils of absentminded driving, and a snarky observation about the state of psychiatry, I am taking a long holiday weekend. I’ll return on Tuesday.

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Diagnosis

dsmThe Diagnostic and Statistical Manual, widely known as the bible of psychiatric medicine, is under revision and the American Psychiatric Association is accepting public comment at a new website.

Medpage Today reports that the revision has already been changed several times in response to these comments. These include several areas within the Sexual and Gender Identities categories, and modifications to the criteria for adjustment disorders and eating disorders.

By contrast, the American Physical Society is not asking the general public to weigh in on the prospects for supersymmetry, nor is the American Economic Association surveying the general public on the properties of dynamic stochastic general equilibria. So much for any pretense that psychiatry is a science.

Hat tip to Tom Amoroso, who called this to my attention though he might not endorse this commentary.

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Absentminded Musings

Here are some thoughts on last week’s absent-minded driver problem.

First a recap of the problem, with a bit more detail than last week:

Each day, Albert leaves his office (at the bottom of the map), gets on the Main Highway and attempts to drive home to his house on Second Street. If he turns too soon (onto First Street) or if he overshoots (going all the way to the north end of the Main Highway), he is mauled by dinosaurs.

Obviously, Albert’s best strategy is to go straight at the first intersection and turn right at the second. Unfortunately, both intersections look identical. Doubly unfortunately, Albert can never remember whether he’s already passed the first intersection.

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Civil Rights Act—Some Final Words

One final word on this 46 year old topic:

Monday I insisted that all reasonable people should be at least mildly disturbed by the diminution of property rights implicit in a ban on whites-only lunch counters.

Tuesday I cited an excellent comment from Jonathan Pryor suggesting that a whites-only lunch counter is itself an indirect assault on property rights insofar as the owners expect taxpayers to foot the bill for enforcement of the whites-only policy (say, by calling the police when unwanted visitors show up).

There are circumstances in which I think Pryor’s argument clearly applies. I cited the case of the man who keeps a barrel of Hershey bars on his front lawn and expects the police to stop children from filching them. Surely this man is imposing a burden on the community over and above the assertion of his own property rights. But I also gave several other examples that gave me pause about the applicability to lunch counters.

This in turn brought forth an insightful comment from Ken B, who points out that the Civil Rights Act itself called for a lot of taxpayer-financed enforcement. The act was passed, blacks sat down at lunch counters, owners attempt to evict them, the police were called.

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Civil Rights and Wrongs

I had planned to get back to our friend the absent-minded driver today, but yesterday’s post on Rand Paul garnered (at least) one comment so good that it deserves to be highlighted.

I said yesterday that the 1964 Civil Rights Law (forbidding racial discrimination in places of public accommodation) infringes on property rights and that all reasonable people ought to be disturbed by that, even if their ultimate judgment is that the benefits of the law outweigh its costs.

Our commenter Jonathan Pryor responded, in effect, as follows (I am paraphrasing):

When you open a restaurant and announce that you won’t serve blacks, you’re not just announcing that you won’t serve blacks. Instead, you’re implicitly announcing that whenever a black person comes in and asks for service, you’re going to call the police and ask the taxpayers to subsidize the cost of your taste for discrimination. You have no property right to those taxpayer dollars.

My first reaction was: This is an excellent point, which I haven’t seen raised before. For the most part, that’s still my reaction. Still, this argument cannot be definitive as a matter of principle, because the same argument applies in many cases where we clearly reject its conclusion. After all, when you open a restaurant, you’re implicitly announcing that whenever a naked person asks for service you’re going to call the police and ask the taxpayers to cover the cost of removal. For that matter, you’re going to call the police every time you get robbed. But we don’t conclude that it should always be illegal to open a restaurant.

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That’s Rich

“It’s now crystal clear what the Tea Party stands for” says Frank Rich midway through a column that makes it crystal clear what Frank Rich stands for, and it isn’t pretty.

Whatever you may think about the 1964 Civil Rights Act as a whole, it indisputably narrows property rights by allowing politicians to dictate the policies of private businesses. Not only is it perfectly reasonable to find that at least a little disturbing, it’s perfectly unreasonable not to find it a little disturbing—even if your ultimate judgment is that it’s a necessary means to a desirable end. Even avid supporters of the Patriot Act ought to acknowledge that it raises legitimate concerns about privacy, even avid supporters of capital punishment ought to acknowledge that it raises legitimate concerns about false convictions, and even avid supporters of the Civil Rights Act ought to acknowledge that it raises legitimate concerns about property rights.

Frank Rich, who equates Rand Paul’s expression of those concerns with nostalgia for the Confederacy, thereby makes himself as scurrilous as those who equate reservations about the Patriot Act with being “on the side of the terrorists”. The “gotcha” game is bad enough when a single thoughtless remark becomes the pretext for dismissing an entire movement. Here the pretext is a single thoughtful remark.

If we are to discredit everyone who is capable of subtler thought than Frank Rich, then there is no hope for the level of public discourse.

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Weekend Roundup

I am amazed and delighted by the many excellent responses to my call for arguments about religion. These will be very helpful to me as I prepare for my debate with Dinesh D’Souza. Keep them coming!

Commenters also had a lot to say about the puzzle of the absent-minded driver. It seems to me that some of the analyses falter by being less than crystal clear about their assumptions: How much can the driver remember (e.g., if he updates his strategy at the first intersection and then arrives at the second, does he remember his original strategy or his updated strategy?), how much he can commit to (e.g. if he updates his strategy at the first intersection, can he commit to sticking to the new strategy at the second? can he commit to the method of updating he’ll use at the second?), how much he can anticipate (e.g. what does he believe about his future updates?), how smart he is (can he use his knowledge of his current strategy to figure out whether he’s already updated and hence what intersection he’s at?) and how sneaky he is (e.g. might he purposely adopt a bad strategy in order to trick his future self into updating to a good one?). I have what I think is a useful way of forcing puzzlers to be explicit about their assumptions, and had planned to post it on Monday, but I keep revising it, so it might be a few more days.

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The Internet to the Rescue

Two Russian girls arrive in DC as part of a travel exchange program for which they’ve paid about $3000. The program promises them jobs on arrival but fails to deliver. Instead, they are instructed to travel to New York City to do “hostess work” in a place called the Lux Lounge. Their American friend, currently in Wyoming, pleads with them not to go, but after some initial hesitation they board a Greyhound bus to New York, insisting that everything is fine.

Where can the panicked friend turn? To the Internet, of course. He posts a plea for help. Commenters jump into action, contacting police and social service agencies, pooling information to figure out what bus the girls are likely to be on, and arranging to have them escorted to a police station. A couple of hundred comments later, the girls are safe and sound. One commenter adds:

This is the best use of the Internet that I, personally, have ever seen. I’m so proud to be a member of this community.

Indeed.

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The Absent-Minded Driver

Until last week, I had never heard of the paradox of the absent-minded driver, but I was recently told that it has some relevance to my encyclopedia article on quantum game theory. That plus the fact that I am a notoriously absent-minded driver myself made me think I should check out the original source. Here’s what I extracted:

Each day, Albert leaves his office (at the bottom of the map), gets on the Main Highway and attempts to drive home to his house on Second Street. If he turns too soon (onto First Street) or if he overshoots (going all the way to the north end of the Main Highway), he is mauled by dinosaurs.

Obviously, Albert’s best strategy is to go straight at the first intersection and turn right at the second. Unfortunately, both intersections look identical. Doubly unfortunately, Albert can never remember whether he’s already passed the first intersection.

Continue reading ‘The Absent-Minded Driver’

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The Better to Hear Your Comments With

My 17 year old stepson is learning Photoshop. For his first effort, he…..well, let’s say he sharpened up this picture of his mom and me:

Meanwhile, the responses to yesterday’s Religion on Trial post have been terrific. Keep them coming.

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Religion on Trial

I’ll be giving a couple of talks at this summer’s FreedomFest on economic growth, the power of incentives, and why More Sex is Safer Sex. More provocatively, I’ll also be going head to head with Dinesh D’Souza in a session called “Religion on Trial: Is God the Problem?”. Dinesh will argue that religion makes the world a better place, and I’ll argue the opposite. We’ll each call on the testimony of witnesses (in my case, Michael Shermer and Doug Casey). After our closing arguments, a jury of twelve, chosen from the audience, will deliver a verdict.

Dinesh has done this before; I haven’t. So I’m calling on you guys to help me out here by giving me your best arguments—either on Dinesh’s side, so I can practice rebutting them, or on my side, so I can plagiarize them.

Remember that the ultimate question is whether religion makes the world a better place, not whether religion is true. (On the other hand, truth becomes relevant if you’re arguing that religion makes the world a worse place by making people believe false things.) So what have you got for me?

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Weekend Roundup

roundup2We began the week with another triumph of capitalism, then moved on to a deep unsolved problem in arithmetic—which you, the reader, have an opportunity to help solve. On Thursday, we were honored with a guest post from the provocative Sup Specie Aeternitatis, offering evidence as to the sincerity of Al Gore’s proclaimed beliefs on global warming. We ended with a neat trick for weeding out job applicants.

I’ll be on the road this weekend so I’m taking Monday off. See you Tuesday!

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Toward a More Efficient Labor Market

In Chapter 9 of The Big Questions, I lamented the great duplication of time and effort that occurs each spring when the top academic departments are all evaluating the same handful of job candidates, and I wondered why departments don’t free ride by simply announcing “We’ll take anyone with an offer from (say) Stanford”.

An anonymous math department chairman reports on his own strategy for cutting down on the workload. He believes that one of the most important determinants of a successful career is luck. So each year, he randomly rejects half the applicants without even reading their folders. That way, he eliminates the unlucky ones.

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From an Eternal Perspective

My favorite new blogger is the pseudonymous Sub Specie Æternitatis, who I discovered when he left a particularly thoughtful comment on the Fair and Balanced thread here at The Big Questions. A little Google-stalking later, I was immersed in his blog. Before much longer, I was in love with it.

Not only is Æternitatis a great writer; he’s also a gracious colleague who (after I introduced myself by email) agreed to let me reprint one of his incisive commentaries as a guest post here. So without further ado:

Al Gore’s Revealed Beliefs

A Guest Post

by

Sub Specie Æternitatis

It is reported that former Vice President Al Gore just purchased a villa in Montecito, California for $8.875 million. The exact address is not revealed, but Montecito is a relatively narrow strip bordering the Pacific Ocean. So its minimum elevation above sea level is 0 feet, while its overall elevation is variously reported at 50ft and 180ft.

At the same time, Mr. Gore prominently sponsors a campaign and award-winning movie that warns that, due to Global Warming, we can expect to see nearby ocean-front locations, such as San Francisco, largely under water. The elevation of San Francisco is variously reported at 52ft up to high of 925ft.

There being very little reason to suppose that the Pacific Ocean would (or could) rise much less in Montecito than in San Francisco, it follows that Mr. Gore just paid nearly $9 million for property, which according to his professed beliefs, will likely soon be literally under water and hence worthless both as a residence and for resale.

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ABC at (Your) Home

abclogoYesterday I told you about one of the deepest problems in arithmetic. Today I’ll explain how you can help solve it.

We’re on the hunt for ABC triples. A brief recap: We start with an equation of the form A+B = C, where A, B and C have no factors in common. We find all the primes that divide A, B or C, multiply them together and call the result D. The goal is to find examples where C is bigger than D.

If I start with 2+243=245, the primes are 2 (which divides 2), 3 (which divides 243), 5 (which divides 245) and 7 (which also divides 245), so D = 2 x 3 x 5 x 7 = 220, and C (that is, 245) is bigger than D. Success! We’ve found an ABC triple.

We want more. A full understanding of ABC triples would allow us to solve some of the hardest open problems in arithmetic. More importantly, the reason we’d be able to solve those problems is that we’d understand arithmetic itself a whole lot better.
The first step is to find a whole lot of examples to help researchers guess at the underlying patterns.

That’s where you come in.

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The ABC’s of Arithmetic

abc123Some of the hardest problems in arithmetic are those that relate multiplication to addition. For example: Is every even number the sum of two primes? This is most assuredly a hard problem—mathematicians have been tackling it for centuries and so far nobody’s solved it. And it relates multiplication to addition. As soon as you talk about primes, you’re (implicitly) talking about multiplication, and of course when you talk about sums, you’re talking about addition.

Or: How many ways can you write the number 2 as the difference of two primes? You can write 2 = 5-3, or 2 = 7-5, or 2 = 13-11. That’s three so far. How many more are there? The betting is that the answer is “infinitely many”, but nobody knows for sure. This problem has stumped some of the best and the brightest not just for centuries but for millennia. And again it relates multiplication to addition. (Well, it relates multiplication to subtraction, but of course subtraction is just addition in reverse.)

The ABC problem has only been around for a few decades, but it’s in many ways the most interesting and important of the bunch. Tomorrow I’ll explain how you can help solve this problem. Today I’ll explain what the problem is.

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Triumphs of Capitalism

Lifted from craigslist, with a hat tip to my sister:

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