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Perhaps it's not the mean but the variance!

April 8th, 2017

Why are only two of the world’s top 100 chess players women?
There may be many factors at play here - including social expectations etc, as well as possible gender differences in average measures of either ability or interest. But it's also possible that a large part of the explanation is just a matter of variance (ie of spread of the distribution of ability or attitude).
As Larry Summers was criticized for pointing out, having one group dominate the top tier is not necessarily evidence that either they are better "on average" or there must be some kind of unfair selection process. The group with higher average of some measure may be under-represented at both extremes if it is more tightly concentrated. And the fact that variations on the y-chromosome may be less likely to be balanced by a partner could be a source of greater variability of some characteristics in males.
Of course, even if this is true, the apparent excess of males at the top may be more visible than the corresponding excess at the bottom, and that may both give mediocre males false confidence and discourage some females from even trying. So it is always worthwhile to counter these effects.

Source: Why are only two of the world’s top 100 chess players women? | Aeon Essays

PostModernism

April 8th, 2017

Stephen Downes comments on critique of post-modernism with reference to whether or not it is a "fact" that tennis balls don't fit into wine bottles.

Despite the failure of a particular bit of language to unambiguously cover all aspects of a situation, It seems likely to me that there are nonetheless real facts about tennis balls and wine bottles. The "proof" of this is in the fact that we would be at least as surprised (though perhaps less entertained) to see a tennis ball in a bottle as a model ship - and so would immediately look for the illusion or trick that needs to be excluded in order to "save" the statement. (This process is a large part of what Imre Lakatos is on about in his book 'Proofs and Refutations' which deals with the same phenomenon in Mathematics.) Yes, language is an inadequate tool for expressing the full content of human understanding, and human understanding may be an inadequate tool for capturing the true nature of reality, but I think it is a mistake to infer from those sad facts that no such reality exists.

Why DT tweets nonsense in the middle of the night

April 3rd, 2017

I like to think of Donald Trump as just obsessively glued to his computer in the middle of the night much like the fat boy he speculated was responsible for the DNC hacking (though more devoted to taking offense and picking fights than to picking digital locks). But that's not entirely right.

The method in his madness (as described in Bradley Eversley's answer (on Quora) to Why do you think Trump always sends disturbing or controversial tweets in the middle of the night? ) is to always find something to grab attention at the beginning of the news day (and the more outrageous the better for this purpose)  as a distraction from whatever more really serious allegations are being made against him or damage he is about to do.

 
Update: And here's a related quote from an article by Stephanie Hayes in the Atlantic:

As a Time interviewer aptly summarized during a recent chat with the president: “Whatever the reality of what you are describing, the fact that [the facts] are disputed makes them a more effective message, that you are able to spread the message further, that more people get excited about it, that it gets on TV.”

Why Were We All Surprised?

April 2nd, 2017

Source: Statistician Nate Silver says conventional wisdom, not data, killed 2016 election forecasts

Actually, I suspect that many people were confusing chances of winning with expected share of the vote. Perhaps not consciously, but not surprising as we are so often presented with percentages as representing the latter. So seeing the number 70 associated with Hillary naturally created a false sense of security in her supporters.

Flying "Cars" were silly - until now

February 9th, 2017

The reason we don't yet have the flying cars imagined by early 20th century "futurists" is not because of mechanical infeasibility (though the energy cost may be substantial) so much as because of the problem of traffic control. Accident avoidance in crowded airspace is beyond the capacity of either expert pilots or centralized traffic controllers, and any vision of replacing cars with flying vehicles had to fail if it depended on human controllers. And it is only now that automated control based on full 3d "vision" in all directions  is becoming feasible. But I don't agree with Uber's new hire that "There will be an evolution from professional human pilots to autonomy over time" because I don't think that human piloted flying cars should ever be allowed off the ground. Source: Uber brings in NASA engineer to build flying cars

Two Challenges

February 4th, 2017

Two very different recent events raise the same issue. How to confront the temptation to abandon one's principles when one's opponents do so without penalty. And in both cases I think The Atlantic has presented a view worth noting.

One is the attack on Al Quaida in Yemen which ended with the deaths of several civilians and a US soldier. Many on the left are crowing that this was authorized by Trump without proper analysis, and I agree that the sources of his advice were unbalanced in that they failed to combine military analysis with any evident input about the long term radicalization effect of a possible disaster (such as what actually happened).

But in Trump's defense, former Obama defense advisor Andrew Exum writes in  Don't Politicize the Failed Yemen Raid:

For the recommendation to have gone forward to the president, the senior leadership of the Department of Defense would have signed off on this operation. And for that to have happened, special operations and regional U.S. commanders would have had to have blessed the planning that went into the operation itself.

The left cannot on the one hand claim Donald Trump is ignorant of military and security affairs, and then on the other hand expect him to second-guess the professional recommendations of his uniformed and civilian military leadership.

I don't agree with Exum that non-military input is properly left out of decisions like this - though perhaps not to the extent of items as trivial as "debating whether or not it made sense to move three helicopters" (and the role of Benghazi nonsense in prompting that level of overdue diligence is worth noting). The temptation to exploit this event in the same dishonest way that the right did with Benghazi is clearly irresistible to some on the left - especially since that sleazy tactic was so spectacularly successful. But it really should be avoided. It's hard to take the high road when the low one is seen to work, but in the end winning without integrity is just another way of losing.

 

The other item is Peter Beinart's piece on how Milo Yiannopoulos Tested Progressives—and They Failed .

...when Trump’s opponents use the danger he and his supporters pose to restrict basic freedoms, there’s a problem.

Which is what happened earlier this week at the University of California, Berkeley, when a violent protest prevented Milo Yiannopoulos, a Breitbart News writer who has made his name by viciously mocking women, trans people, and African Americans, from speaking on campus.

With or without violence, the de-platforming was probably misguided although the protest itself was not. Let us rather all hear the trash with which the young Republicans want to be identified - and not provide any excuses for them to play the martyr or for those who wish to de-platform other views that we may share but which they declare offensive.

Update(Feb3):But . like Robert Reich, I wouldn't "bet against" a suggestion that the violent protesters who closed down the Yiannopoulos event were right wing provocateurs rather than real left wing opponents.

Giant Pterosaurs 

January 28th, 2017

 

How did they fly? (or did they always have strong winds or cliffs to jump off?)

And why do they have beak-like snouts like birds? (while bats do not)Source: Fossils of giant pterosaurs found in Transylvania

The Science is Clear?

January 28th, 2017

Anyone distressed by the amount of distrust of real science in the world today need only look at the overstated (and actually false) headline in this bit of "science" journalism to find an explanation.

Of course torture doesn't always work. And it very likely would only rarely be the most effective way of getting information. But I can tell you for sure that it can sometimes work because I know that there are circumstances in which it would work on me.

What's in the article is mostly not false

Enhanced interrogation techniques often lead to unreliable information; instead, we might want to follow the lead of a noted "nice-guy" Nazi.

but it does not support the headline. And regardless of what the authors intended, that headline stands as the position of a self-styled "science" magazine.

Source: The Science is Clear, Torture Doesn't Work - D-brief

Robert Reich (Trump’s Plan to Neuter the White House Press Corps)

January 15th, 2017

And he repeatedly lied. But the media in attendance weren’t allowed to follow up or to question him on his lies.For example, Trump wrongly stated that “the Democratic National Committee was totally open to be hacked. They did a very poor job. … And they tried to hack the Republican National Committee, and they were unable to break through.” Baloney.FBI Director James B. Comey said there was evidence that Republican National Committee computers were also targeted. The critical difference, according to Comey, was that none of the information obtained from the RNC was leaked. Also, according to Comey, the Russians “got far deeper and wider into the [DNC] than the RNC,” adding that “similar techniques were used in both cases.”

Source: Robert Reich (Trump’s Plan to Neuter the White House Press Corps)

Unfortunately this is a poor example. The DNC was hooked by a very simple phishing operation and whoever was responsible for advising Podesta did indeed do a "very poor job" (and so by implication did whoever hired him right up to Podesta and the DNC leadership themselves). Almost cetainly the RNC was "also targeted" by "similar techniques" but as Comey said, the Russians  “got far deeper and wider into the [DNC] than the RNC.” This is totally consistent with Trump's claim that "they tried to hack the Republican National Committee, and they were unable to break through.” That claim may be "Baloney", in that other techniques did get in to the Republicans and the discovered embarassing information was not released, but there is nothing in Reich's rebuttal to justify that counter-claim.

Does Networking Make Us Smart or Stupid?

December 10th, 2016

Stephen Downes links to Amy Burvall on her daughter's reliance on her friend Ellie as a source of information.

I think the question in her antipenultimate paragraph: "Do we crave more temporal, less formal interactions, even if it means the information we receive is at risk for being less accurate?" should be answered with a resounding "Yes!" - which means that it is quite possible that the way we most naturally use networked knowledge is making us stupider rather than smarter. Of course other possibilities exist and the network also allows us to access central sources which are subject to corrective review from a wide variety of directions, so contra Nicholas Carr I am not worried about Google Making Us Stupid but neither do I share David Weinberger's confidence that Networked Knowledge Makes Us Smarter.

In any case, it's the long-range structure of the network that matters, and the evidence from Nov 8 and June 24 is that the network is disconnected to such an extent that those of us in the "smart" bubble were unaware of the extent of the "dumb" one.

Source: #rawthought: Your Ellie – On the Primacy of Networked Knowledge | AmusED via #downes

Should Schools Teach General Critical-Thinking Skills? 

December 5th, 2016

This article claims that "critical thinking" should not be taught as an independent discipline - largely because success in any particular area is allegedly more dependent on detailed knowledge of that area. But one of the main reasons for teaching "critical thinking" is to train people to evaluate the arguments and claimed expertise of others in areas where they do NOT have loads of experience or knowledge themselves. As such, it is perhaps THE most important thing a person can learn .... if indeed it can be taught.

But an important point made or implied in the article is that there is precious little positive evidence that those who claim to be teaching critical thinking are having any measurable success. This is certainly an appropriate application of critical thinking to the claims of those who claim to teach it. But it does not address the question of whether or not those skills should be taught if possible. A proper application of critical thinking to the article itself requires us to investigate whether or not the graduates of a "critical thinking" class are  or are not better able to identify a charlatan than those who took the "placebo" class. Being too lazy to do so myself I will leave this as an exercise for the reader.

Some Math Ed Stuff 

December 5th, 2016

Inverse Functions are certainly a minefield for students, and the situation is not helped by teachers' use of sloppy language to describe the concept and the prescription of a mindless ritual for answering assigned questions.

This article points in the right direction although it's not quite perfect in my opinion1. But what got my friend Bruce to comment was one of the authors taking the objection to explanation by procedural prescription into another area where it might be less apt - namely the concept of average value.

Note 1:
Expressions like "the inverse of y=f(x)" are problematic because the relation defined by y=f(x) is the same as that defined by x=f^-1(y) and does have inverse relation defined by y=f^-1(x). So, contrary to the article, it is in some sense correct to say that the "the inverse of y=f(x) is y=f^-1(x)", and the formal definition of functions as sets of ordered pairs does justify "switching x and y" if this is interpreted and explained properly.

Prepare to be inspired (fromBBC via Butterflies and Wheels)

December 5th, 2016

Connie, this is for you:

The BBC has an annual series called 100 Women. BBC 100 Women names 100 influential and inspirational women around the world every year. We create documentaries, features and interviews about their lives, giving more space for stories that put women at the centre.

Source: Prepare to be inspired - Butterflies and Wheels

Liberal Elite Give Thanks to Trump Voters 

November 26th, 2016

By Rob CoxNEW YORK (Reuters Breakingviews) - This is the week when all Americans give thanks for the bounties bestowed on them by the Blessed Creator...

 

Source: Cox: Liberal elite owe gratitude to Trump voters | Reuters

Munk Team is Irresponsible 

October 3rd, 2016

Source: Munk Debates - U.S. Election

This is a very misleading press release! It leads the non-reader to conclude that the resolution was approved by the audience when the "winning" team just managed to reduce its rate of disapproval. This result would only be a "surprise" if one had advance expectation that the Con team were the better debaters (which, with no disrespect to the Con team, would certainly be foolish given the people involved).

Why I love the Jehovah's Witnesses

August 9th, 2016

In general, I find that commitment to a text which one can interpret for oneself is less harmful than commitment to some class of annointed interpreters of such a  text. And although I don't share such a commitment myself, I do find much in the bible that I agree with, as well as excuses within the text for discounting those parts I find offensive. By and large I find the JW interpretations to be supportive of a humane treatment of our fellow beings and, with or without the biblical support, I find their publications to present fair and reasonable advice regarding human behaviour.

But what I particularly enjoy in those publications is the "Was it Designed?" feature in their 'AWAKE!' magazine. This regular feature describes some wonderful aspect of our biological world with the conclusion "What do you think? Was it the product of evolution? Or was it designed?". The puzzles posed are sometimes easy but often quite challenging and I cannot imagine a better set of resources for a Biology teacher wishing to encourage students to see how the evolutionary algorithm so often produces designs which improve substantially on the best that an "intelligent" human might have devised.

Source: Website Search | JW.ORG

Possible New Physics at CERN 

May 7th, 2016

Matthew Buckley is writing a nice series of articles for the Boston Review about The Search for New Physics at CERN . He is aiming to give enough of the background for readers to get an idea of how recent observations may indicate something beyond the "standard model" of elementary particles. If confirmed by subsequent observations this will provide a significant constraint on the kind of theory that can bring gravitation into the big house of quantum theory - and by doing so may help to focus the currently diverse efforts on a track that has the best chance of success.

This is a great series of articles, but I do have one quibble.

In his discussion of the Higgs discovery Buckley says:

"How likely was it that the bump was due to chance? Not very likely: 1 in 3,488,560."

But I think there is a difference (recently pointed out by the ASA in its "statement on P-values") between the likelihood that the bump *was* due to chance and the probability that such a bump *would* occur in the absence of non-chance effects.

I suspect that Buckley is well aware of this as he does not make the same error in his subseqent statement about the new observation:

"Similar calculations show that the ATLAS bump at 750 GeV could occur by chance only once in 6285 tries."

Indeed his expressed fear of being trapped into working on the explanation of an effect that is not real shows that he doesn't really think that the probability of this new bump being just a chance occurrence not due to a real effect is as low as 1 in 6285.

Trump Accepts GOP Nomination - Concedes Presidency to Hillary Clinton

May 3rd, 2016

Celebrating his status as the presumptive nominee of the Republican Party, Donald Trump thanked his family and supporters, and was as magnanimous as he could manage regarding his recent opponent Ted Cruz. But he turned somewhat ungracious in his concession of the actual presidency to Hillary Clinton who, he predicts, 'will be a poor president' .

No Market-Driven Solution?

March 26th, 2016

British journalist Paul Mason seems to echo Naomi Klein's This Changes Everything in his claim that There Is No Market-Driven Solution To Our Climate Catastrophe

But although I am no fan of concentrated private capital I think both of them beg the question by overlooking the constraints that must inevitably be included in the definition of any market. These almost always are expected to include laws against theft and murder, and the solution to all environmental problems including climate is just to also include the prohibition of any permanent environmental impact. If "dumping" of wastes into the atmosphere and oceans was just flat out prohibited (with the onus being on any economic actor to retain and maintain control over any by-products of its activity) then the market would immediately favour whatever source of energy (or anything else) could be made most cheaply within that constraint.

(I am not claiming that this would be easy, just that it is quite independent of solving the problem of fair distribution of wealth and/or opportunity)

Saudi Oil Minister Gives Good Advice

March 26th, 2016

Saudi Arabia's Oil Minister Suggests Canada, Others Will Have To 'Get Out' Of Oil

(He left off the word "consumption" but I'm sure that's what he meant)