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If you're looking for people who generate a profit from their time, the curve is almost certainly U-shaped based on my now not-so-light 30+ years in the trenches.

The skill distribution doesn't have to be U-shaped to produce a U-shaped distribution. All there has to be is a threshold of skill that must be reached to perform effectively: http://www.tjradcliffe.com/?p=...

I liken this to a wall-climbing task in an obstacle course: some combination of height/weight/strength is necessary to get over the wall. If you measure them individually you'll see broad distributions with soft correlations with ability to get over the wall (because short/strong/light people will be able to do it and tall/strong/heavy people will be able to do it, but short/strong/heavy people won't and tall/weak/light people won't, etc). The wall-climbing task requires the right combination of a small number of such skills to be over some threshold. This trivially (as the simple model in the link shows) generates the observed U-shaped distribution in programming outcomes.

People who claim that anyone can be taught to code well enough to pass a first year computer science course have the opportunity to make a very simple, compelling argument in favour of their thesis: tell us how to teach people to program! If you can do that--if you can get rid of the U-shaped mark distribution that has been documented in first year computing for decades despite all kinds of efforts to understand and deal with it, your argument will be made. Everything else is just hot air: ideological and unconvincing.

There are certain things we know do not cause the bimodal mark distribution in first year computing:

1) Bad teaching (because the issue has been researched and any number of caring, intelligent teachers have thrown themselves at it, and anyone's sucky first year computing prof does not disprove this)

2) Language (because the bimodal mark distribution persists in all languages)

3) Years of coding experience of incoming students (because if that were the case it would have been identified as the differentiator in the decades of research that have gone into this: someone with no coding experience can do as well as someone with years... if they are over some threshold of skill.)

So while it's fun to watch equalitarian ideologues tub-thump this issue, they unfortunately bring nothing to the discussion but ideological blather. The U-shaped, bimodal, mark distribution in first-year computing is robust evidence of a threshold of some kind that people have to be over to code well. There may be other thresholds higher up the scale (I've seen estimates that 25% of coders will never get OO... god knows what the figure is for FP, which I'm still struggling with myself.) But the claim "It would be dreadful if everyone can't code!" is not an argument, it's an emotional outburst, and we need to focus on the data, not the way we wish the world is.

Personally, I would love it if we could figure out how to teach coding better. I see journalists, economists, politicians, business-people, all sorts who are dependent on coders to help them out on the most rudimentary questions. If we could teach everyone to code the level of data-driven discourse would go through the roof. But I'm not counting on that happening any time soon.

there is an infinitesimally small chance that it was engaged by accident.

And since air disasters necessarily depend on extremely low-probability events, this is not an argument for the proposition "therefore this was most likely not the cause".

We know that whatever happened it had an outrageously low probability. This makes speculation in advance of data useless, because there are an almost unlimited number of highly improbable things that could have happened, and anyone who thinks they can imagine their way to the correct one is innumerate: http://www.tjradcliffe.com/?p=...

The simulation argument is nonsense that is only plausible to people who either haven't given it any thought or don't know any physics: http://www.tjradcliffe.com/?p=...

They'll keep doing it till they're kept so busy at home that they don't have time for this foreign adventurism.

By "kept so busy at home" you mean "engaging in productive trade", right?

Because it certainly wouldn't make any sense to suggest that bombing them, for example, is "keeping them busy" in any materially useful sense, since we have overwhelming empirical data that bombing and any other form of military assault has the primary result of engendering resistance.

Furthermore, "at home" is Belgium for the people involved in this action, and "at home" was France for the blasphemophobes who murdered the blasphemers of Charlie Hebdo.

You are right that this is an asymmetric war, but you don't seem aware that that requires tactics very different from bombing or other military action in many cases. Limited military assaults can serve definite purposes, as the case of ISIS shows, but the real war won't be won on the battlefield any more than the war against the Soviets was won on the battlefield.

In fact, there not being a battlefield in any conventional sense was a requirement for winning against the Soviets. Even setting aside the problem of nuclear weapons, if we had met the Soviets on the battlefield we can say with near certainty that the population would have rallied 'round the commisars, and the Soviet Empire would have never fallen.

As such, our tactical response to Islamists should be primarily--but not exclusively--non-military. It should be economic, political, satirical, even poetical: http://www.tjradcliffe.com/?p=...

It took hundreds of years for Christians to let go of blasphemophobia. It may take as long for Muslims to let go of theirs. We should be in this for the long haul, and while we should be willing to kill and die now and then, if anyone suggests those should be the primary activities involved, they are simply expressing a profound ignorance of humans, and history, and warfare (both its costs and its effectiveness, which bellicose emotionalists often get wrong.)

By way of example... Francis said jokingly, throwing a pretend punch his way.

So is it an example, or a joke?

If it's an example, what is it an example of?

If it's a joke, then it's in spectacularly poor taste.

"Ha ha some blasphemophobes have just murdered some blasphemers, let's talk about how funny it is to beat up people who insult your deeply held beliefs."

Blasphemophobia kills, and it's time we started calling it out and saying it is never appropriate to meet blasphemy with violence of any kind: http://www.tjradcliffe.com/?p=...

To say otherwise is to be one of those people who claim, "Michael Brown was a bad kid so really, we shouldn't be too hard on the cop who shot him down on the street, because hey, the cop thought that black kid was like an unstoppable demon. Wouldn't you shoot an unarmed man under those circumstances?"

Likewise, "Hey, you'd punch someone out who insulted your mother, wouldn't you? So can't you understand just a little bit how someone could be so angry you insulted their religious beliefs that they'd plan and execute the murder of twelve people who had never done any physical harm to anyone?"

Same lame excuses. Same lame apologetics.

Along with that they should declare that every time a reporter working for one of their papers is killed in an attempt to silence them, they will again run Muhammads image on the front page of their papers. The responsibility for the image will be the attackers and they'll burn in hell for their idolatry. Want to stay out of hell? Stop murdering people.

"The satire will continue until the killing stops": http://www.tjradcliffe.com/?p=...

We should all be making as much fun of Islamists and their blessed prophet as we can. I like my caricature of Mohammed more than yours, though:

~0:-{=

(complete with bomb in turban, like in the Jyllands-Posten cartoon: http://www.zombietime.com/moha...)

Perhaps the best strategy in this case would be for all creative artists and writers to produce as much content as they can and Creative Commons license it, so the content can all be broadcast everywhere and we all agree to post and publish it in every medium on every forum possible.

This.

My own contribution to the cause (CC NC Attribution Share-Alike), a satirical poem based on Lewis Carol's "The Walrus and the Carpenter": http://www.tjradcliffe.com/?p=...

The Peaceful Prophetâ(TM)s followers
were shooting infidels,
beheading them with axes
and flinging them down wells
proclaiming, âoeIâ(TM)m for Paradise!â
while making Earth a Hell.

Apologists snapped angrily
because they thought the war
against Enlightenment and law
was all of that and moreâ"
âoeHow rude of people to point out
religionâ(TM)s blood and gore!â ...and so on...

Climate change is a non-issue. The temperature has NOT risen since 1998.

You've gotta stop using 1998 as the benchmark year.

We are indeed in a hiatus with respect to the thermodynamically meaningless quantity "global average temperature": http://www.tjradcliffe.com/?p=...

Anyone who claims that the hiatus is a result of cherry picking is a liar or a fool, but like the trained monkeys they are if you use the year 1998 they will bark "cherry picking" just as surely as Pavlov's dog salivated at the bell.

Far better to say, "The temperature has not risen in the past decade or so... the precise point you start with doesn't really matter in the 2002-2004 range." This will probably still get you a "Cherry picking!" response because Warmists are stupid, but they have a better chance of looking stupid when they do so.

Now of course, you also have to admit that any given decade in the past century has reasonable odds of having a temperature profile as flat as the most recent one, so making any very strong inference from the perfectly real, non-cherry-picked hiatus is going to make you look stupid too, but that's what this debate is all about: which side can look the most stupid most of the time?

Fossil finds are a very sparsely sampled distribution, which means that while the earliest evidence for art has been pushed back hundreds of thousands of years, the earliest making of art almost certainly predates it by a much longer span: http://www.tjradcliffe.com/?p=...

This is not a new idea, but it's one that continually evades reporters in this area. The data of first discovery of a sparsely sampled distribution is almost certainly much, much later than the first instance of the thing being sampled.

I don't think even-handed coverage is possible, when journalism as a whole is essentially paid trolling for one agenda or another.

We can at least hope for news stories that convey a minimal amount of relevant background information: http://www.tjradcliffe.com/?p=...

The cost of supplying a few concrete facts relevant to the background of each story is apparently too much for various news outlets, but with the kind of crowd-sourcing Larry is suggesting this could be done. It'll be interesting to see how this effort evolves.

Ideology may always be with us, in the sense that that "there is no view from no where" but it is (precisely!) equally true that "there is no view of no where", and modern news organizations apparently forget that. They routinely distort the news to the point where it is almost unrecognizable (ask anyone who has been close to any matter reported in the news). Part of the value of sites like /. is that sometimes we get people here who can untangle the journalist's mix of ideology and ignorance from the subject of the story, which gives us all a better view of reality, which of course is possible (your smartphone wouldn't work if it wasn't.)

This is a general problem with the way people infer origin dates from sparsely sampled distributions: http://www.tjradcliffe.com/?p=...

The earliest anatomically modern human fossils date from about 195,000 years ago, and people often say on this basis that anatomically modern humans appeared about 200,000 years ago, which is statistically illiterate at best.

Maybe people in the field know better, but I've seen an awful lot of claims like this and even in the semi-professional literature there seems to be a strong tendency to assume origin dates based on "date of earliest discovery plus a bit", which is just the wrong way to do it.

While you are correct that the airborne vector isn't significant need I remind you that Ebola is not a disease whereby the person infected with it gets a mild fever and minor headache and the cure is two aspirin tablets?

Sure, but that has zero bearing on the degree of concern people should have about the epidemic potential of Ebola in any country with a first-world health care system (Nigeria, say, or parts of the US outside Texas.)

The thing fearmongers like the GP are all about is the attempt to create a sense that Ebola could actually be spreading like the flu, which is so trivially false it isn't even worth mentioning. Yes, PPEs that include good respiratory protection should be part of the standard patient-handling protocol, and all due care should be taken to avoid droplet transmission, but Ebola's almost complete lack of aerosol transmission is and will remain a substantial barrier to the population risk the disease poses: http://www.tjradcliffe.com/?p=...

No, it really doesn't. It's too hard to transmit, and almost certainly will remain so.

Saying it has "the potential" to wipe out half of humanity is mindless fear-mongering. The US has more guns that people, and therefore it is true to say that guns in the US have "the potential" to kill everyone, but I don't see anyone panicking about it, just arguing whether 30,000 deaths per year is an acceptable loss. To use "potential" in the sense you are is almost completely meaningless.

I think it takes millions of rapists (mostly men natch) to reach that number.

And you would be wrong. At least, you would be wrong if you are implying anything other than the majority of rapes are committed by a small minority of predatory men.

How small?

75-80% of rapes are committed by 4-5% of men: http://www.tjradcliffe.com/?p=...

That's still seven or eight million men in absolute terms, of course, but far fewer than what is erroneously claimed by the old, failed, misandrist "rape is nothing less than a conscious conspiracy by all men against all women" model.

It is easy for us, as humans, to leap from "all rapists are men" to "all men are rapists". Even if the former proposition were true (it isn't) the latter is unrelated to it.

There is a population of sociopathic predators in our midst. Most of them are men. All of them are dangerous. Their victims are both men and women (we don't even know what the rate of male victimization in sexual assault is... all we know is that the reported rate is much lower than for women, but it would be, wouldn't it?)

Focusing on men vs women rather than citizens vs predators is exactly what the predators need to keep on preying on the innocent. It's time we stopped doing that.

I dont know about the satellite data, but in the case of the surface record, there can be no scientific reason to adjust temperature measurements. Such measurements are the core of the science .. things are measured and the values are what they are. It is never scientific to process past measurements and then call them "corrected" (which is what the climate folks are doing with the surface record.)

That statement is false.

Science is the discipline of publicly testing ideas by systematic observation, controlled experiment, and Bayesian inference.

There are many reasons why one might get the idea that past temperature records have systematic inaccuracies that may require correction. The urban heat island effect is one large one, which tends to produce higher uncorrected temperatures over time. The phenomenon is simple in principle: cities generate heat, have more dark surfaces, and trap heat in buildings etc which gets re-radiated at night. Weather stations sited near cities have typically become increasingly surrounded by them over the past century, because cities have grown.

Ergo, the instrumental temperature record from many stations needs to be corrected downward to account for this effect, if we want to pull out the environmental temperature (what we are generally interested in.)

This is what we do all the time in science. We start with a raw instrumental measurement and then apply various theory-dependent corrections to infer the underlying quantity we are actually interested in. For example, at the LHC, physicists measure the raw detection rates of various particles in multiple detectors, and then correct them for known background rates etc (frequently using ancillary measurements in the same detectors to determine those rates) to infer the presence (or absence) of the Higgs boson.

What you are saying is "never scientific" is in fact the core of the scientific process, and it makes no difference if the original data were taken today or fifty years ago: they are open to justifiable correction by anyone who sees fit. If you have the idea that the corrections applied are unjustified, feel free to challenge them, but please don't go promoting your fallacious vision of what science is and how it works.

And by the way, if you are interested in what an analysis of the uncorrected instrumental temperature record looks like at one particular station, here is an example: http://www.tjradcliffe.com/?p=...

It just boggles my mind that anyone could be so naive as to think emissions can be curbed significantly, in a relevant time frame, by multilateral international agreement.

No one believes that emissions can actually be curbed, but no one cares because no one (or hardly anyone) is actually interested in solving the problem. They are far more interested in using the problem as a justification for controlling other people, in exactly the same way that anti-abortion crusaders don't care about reducing unwanted pregnancy and anti-drug crusaders don't care about reducing drug addiction (not use, addiction and abuse... you know, the things that actually cause the vast majority of drug-related problems.)

We know that prohibitionists of all kinds don't care about the problems they claim to be solving, because prohibition is always a lousy solution. We've known that about drugs for decades. We've known abstinence-only sex education and restricting access to contraceptives increases teen pregnancy. But the people who advocate those things don't care about teen pregnancy: they care about controlling people. Same with drug warriors.

And it's the same with abstinence-only GHG opponents. If they cared about the problem they would be massively pro-nuclear (some are) and more than willing to explore geo-engineering possibilities, however unlikely.

Think about it: there is a class of person who claims that anthoropogenic climate change is likely to produce a civilization-ending event, but are adamantly opposed to even researching any potential solution that doesn't fit into their bizarrely Puritan moral universe.

With the radiation dose equal to a few minutes of flying at 35,000', use of the system poses less of a risk than the flight.

The dosimetry that generates this number is inappropriate for this kind of machine.

Short version: the dosimetric standard used by the company to claim these devices are safe assumes that the incoming x-rays are absorbed uniformly over the whole body, but in fact they are primarily absorbed in the skin. The skin dose is therefore much higher than the meaningless and irrelevant "whole body dose" that the dosimetric rig used measures.

My own take as a physicist who knows a bit about this stuff can be found here: http://www.tjradcliffe.com/?p=621

The important fact is at the end: "That is, 'Preparing a photon in the same quantum state will sometimes result in photons in different physical states' does not imply 'Preparing a photon in different quantum states will sometimes result in photons that are in the same physical state'. The former proposition is the statistical interpretation. The latter is the assumption that the authorâ(TM)s argument depends on."

Since the author's assumption has nothing to do with the statistical interpretation, their argument says nothing about the statistical interpretation.

But it's interesting to see what some of the authors have to say about it. Here's a comment from Jim Butcher

Curiously, I was looking at the latest Dresden Files book in Amazon.com last night: it's a buck more expensive than the hardback version.

I wonder if this feeling of rip-off pricing could have anything to do with rate of piracy?

I won't pirate stuff, but I sure as hell won't pay more for DRM-crippled bits than I will for dead trees between hardcovers, even when the DRM is easily stripped: http://www.tjradcliffe.com/?p=639

I work in a radiation industry and know a considerable amount about X-ray physics and medical imaging, and these scanners should never have been taken into use for public screening.

I'm a physicist who has worked in radiation transport, and couldn't agree more.

You get far more additional radiation from flying in the airplane than you do from the scanner.

What is the skin dose from the "additional radiation" you get from flying on a plane and how does it compared to the skin dose from the scanners?

There has been just one study done on these scanners and it had a completely inappropriate experimental design to measure the actual risk. It was a bulk dosimetry study that to first order took the skin dose (which is what these machines actually produce) and divided it by the whole body mass, producing a number that was completely meaningless (but very, very low).

My critique of that study from the point of view of a radiation transport physicist can be found here: http://www.tjradcliffe.com/?p=114

Thanks... that clears up my basic confusion. I didn't see how it could be done with linear optics either, but not being in the field wasn't sure if there wasn't something I was missing.

Having read the paper in more detail I'm not overwhelmed by their argument.: "That is, 'Preparing a photon in the same quantum state will sometimes result in photons in different physical states' does not imply 'Preparing a photon in different quantum states will sometimes result in photons that are in the same physical state'. The former proposition is the statistical interpretation. The latter is the assumption that the author’s argument depends on."

The authors (as far as I can see) don't claim the latter to follow from the former. However in my understanding their point is that if two different physical states imply two different quantum states then the quantum state is part of the physical state (because the quantum state then is uniquely determined by the physical state). And since that's what they want to prove by contradiction, they of course have to assume that this is not the case, i.e. that the same physical state can be part of different quantum states.

Thanks... that clears up my basic confusion. I didn't see how it could be done with linear optics either, but not being in the field wasn't sure if there wasn't something I was missing.

Having read the paper in more detail I'm not overwhelmed by their argument.: "That is, 'Preparing a photon in the same quantum state will sometimes result in photons in different physical states' does not imply 'Preparing a photon in different quantum states will sometimes result in photons that are in the same physical state'. The former proposition is the statistical interpretation. The latter is the assumption that the author’s argument depends on."

OPERA has just found that either neutrinos travel 0.03% faster than photons we've measured, or their equipment has an unknown systematic error.

Or they screwed up the data analysis, which is my bet: http://www.tjradcliffe.com/?p=543

“The power of accurate observation is commonly called cynicism by those who haven't got it.” -- Bernard Shaw

The clearly the /. editors or the dimwit who submitted this story are not cynics, because they certainly lack the power of accurate observation. This report speculates that the reactor pressure vessel may have melted, but for some unaccountable reason the summary suggests that the containment may have been breached.

There are probably better discussions out there, but here's my take on the reactor design, which includes a pretty picture from Wikipedia that gives an idea of the difference between the pressure vessel and the containment.

This story is pure sensationalism by abstraction and amplification. The mental health effects of fear due to misinformation, sensationalism and lies surrounding nuclear accidents of this type are far greater than the physical health effects, and I dearly hope one day the ignorant assholes who promulgate these kinds of sensationalistic accounts get their propper cumuppance: a massive class-action suit brought by the victims of their voyeuristic fearmongering.

UCSF suggests that measuring this radiation on the skin would result in a larger value.

It would. The TSA numbers come from taking the total dose, which is deposited in the skin and adjacent tissue, and dividing it by the mass of the body. This is a bit like having a person hold a sixteen tonne weight to reduce the effective dose of a drug: if you divide the drug quantity by the mass of the person plus the mass of the completely unaffected dead weight, you can get any dose number you want.

Skin dose is what matters for the backscatter machines, and the dosimetry done on them is appropriate only to whole-body dose.

Why are drug smugglers being kept in Guantanamo?

For the same reason innocent people are being held in Guantanamo Bay: all power gets used, and without the check of a robust legal system police powers will be used however the police feel like using them. In this case the "police" are the various DHS agencies and the US military, and they have been given free reign by the American government to operate beyond the law.

Unless people being held in Gauntanamo have full access to the US legal system there will be a very substantial levening of innocents and people guilty of crimes unrelated to terrorism there.

Many of the demotivator [despair.com] posters [despair.com] fit the bill here.

How about this one, inspired by one of my poems, which was itself inspired by Joss Whedon's "Firefly".

It doesn't really make the health risk to crew any more substantial.

You're comparing apples to organgutans, and you have no basis for making dosimetric claims regarding x-ray backscatter devices, as there has never been any proper dosimetry done on them.

But these low-intensity x-ray machines in the airports are low enough energy that the radiation is mostly absorbed by the skin...

Pretty much. Here's a simple explanation of the problem from the point of view of radiation transport physics.

The standard dosimetric techniques by which these scanners have been tested are not appropriate to the kind of dose distribution they produce.

With regard to flying and skin cancer: if there is an increased incidence of skin cancer due to flying it will likely be due to heavy charged particles from cosmic rays that interact with the metal in the plane. Such heavy charged particles will have a wide range of energies and the whole lower end of the spectrum will stop in people's skins.

You can find scientists that warn lots of stuff. There are many more scientists that are telling those first scientists to shut up.

For an explanation of what is at issue, have a look at my take from the point of view of a radiation transport physicist. I've worked in various areas of medical physics, as well as detector design for particle physics, and I am confident in saying that the dosimetry done on these devices is almost entirely inappropriate for the dose distributions they produce.

This does not mean the devices are unsafe, but it does mean no one actually knows what the skin dose is, and the manufacturers and regulators are not rushing out to make the appropriate measurements.

And if anyone is telling anyone else to "shut up" they aren't engaging in science, but anti-science.