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  1. "Economist" article on Wavy Lenses Extend Depth of Field in Digital Imaging · · Score: 3, Informative
    The Economist had a nice descriptive acticle about wavefront coding a couple of month ago. Interesting stuff.

    http://www.economist.com/science/tq/displayStory.c fm?story_id=1476751

  2. Prior Art -- The Economist's "Recession Index" on Web Log 'Word Bursts' Could Identify New Crazes · · Score: 2, Interesting
    Since the early '90s, the Economist has from time to time published occasional tongue-in-cheek articles about its "Recession Index", a useful leading indicator of the state of the US economy -- namely, the number of times the 'R-word' appears per month in the New York Times and the Washington Post. This appears to correlate strongly with the future state of the economy...

    eg:

    Dec 10, 1998

    Nov 21, 2002

  3. Drug abuse surveys etc on Randomizing Survey Answers For Accuracy · · Score: 2
    I believe this technique (or the variant above with a single d6) has been used as a standard textbook example in the literature on Bayesian methods in biomedical statistics.

    ISTR it's in Tanner's book on Gibbs sampling, as a method used to extract accurate population estimates about embarassing, personal or even incriminating subjects, such as past exposure to STDs, sexual orientation, or the use of particular controlled drugs.

    Of course, your survey has to be big enough so that the expected number of true positives (N.p) stands out above the expected uncertainty in the number of false positives, approx sqrt(N.p'.(1-p'). If p is small, N may have to be really quite big.

  4. Re:pregnancy? on Crypto Restrictions Are Taking Over the World · · Score: 2
    And when, oh enlightened one, did it change?

    The current UK legal position is set out in the European Union's Pregnancy Directive, which came into force in 1995, and the UK Employment Rights Act (1996).

    All workers, irrespective of length of service, are protected from being dismissed on the grounds of pregnancy or maternity; and are entitled by statute to at least 14 weeks of maternity leave (longer, in most cases).

    However, there were substantial protections in place even before these Acts.

    What exactly is this mystical support for the unemployed? That they are garaunteed to *be* unemployed?

    Unemployment % Rate: UK 5.2%, USA 5.9% (The Economist, 13.7.2002)

  5. Re:some salt, some truth on Will Earth Expire By 2050? · · Score: 2
    America's consumption 'footprint' is 12.2 hectares per head of population compared to the UK's 6.29ha while Western Europe as a whole stands at 6.28ha. In Ethiopia the figure is 2ha, falling to just half a hectare for Burundi, the country that consumes least resources

    The Economist magazine this week has a long, multi-article survey on the economics the environment and sustainable development, together with an editorial, an uncompromising cover ('CO2AL - Environmental enemy No. 1'), and an interesting science article on how to burn coal without releasing the CO2 into the atmosphere.

    One point it makes about the WWF's environmental footprint figures is that 'the biggest factor by far is the land required to absorb CO2 emissions of fossil fuels. If that problem could be managed some other way, then mankind's economic footprint would look much more sustainable'. ('Working miracles').

    Although it notes that 'any reduction in emissions has to start slowly, because the capital stock involved in the global energy system is vast and long-lived', the survey goes on by saying that 'that pragmatism must be flanked by policies that encourage a switch to low-carbon technologies when replacing existing plants... Governments everywhere (but especially in America) need to send a powerful signal that carbon is going out of fashion. The best way to do this is to levy a carbon tax. However, whether it is done through taxes, mandated restrictions on greenhouse gas emissions, or through market mechanisms, is less important than that the signal is sent clearly, forcefully and unambiguously. This is where President Bush's mixed signals have done a lot of harm: America's industry, unlike Europe's, has little incentive to invest in low-carbon technology. The irony is that even some coal-fired utilities in America are now clamouring for CO2 regulation so that they can invest in new plants with confidence' (Blowing hot and cold).

    ('A clause in America's Clean Air Act exempts old coal plants from compying with current emission rules, so much of America's electricity is now produced by coal plants that are over 30 years old. Rather than closing the loophole, the Bush administration has announced measures that will give these dirty old clunkers a new lease on life' (Editorial)).

    The survey as a whole is usefully level-headed. One thing that's well worth a look is the second table on this page: an interesting perspective on different ways the world changed over the 20th century. ('A century that changed the world', in the section Flying blind)

  6. or Waterloo, 1815 on Information Valuation - The Most Buck for the Bits? · · Score: 2

    Famously, the Rothschild brothers (who organised the finance for most of the 1815 alliance against Napoleon) got news of the victory at Waterloo back to London a day ahead of anyone else ... and did rather well.

  7. Perhaps an asteroid AND a lava flow on Lava Flow May Have Caused Extinction · · Score: 2
    It's been suggested that if you get an asteroid impact, the outgoing shockwaves may be refocussed by the curvature of the earth to produce a region of very high stress in the area of the globe diametrically opposite from the impact point. If this happens to co-incide with an area of weakness in the earth's crust, the suggestion is that the stress from the impact could actually cause the crust to rupture, and trigger a wide-area volcanic event.

    The Chicxulub crater in Mexico is very nearly opposite the Deccan traps, which have both been fingered for the extinction of the dinosaurs 65 million years ago. There is also a possible large impact site in Australia of the right age, which would have been almost exactly opposite the Siberian Traps at the time of the Permian extinction 250 million years ago. On the planet Mercury there is a gigantic impact crater called the Caloris basin, which is also directly opposite "weird terrain" caused by focussed shockwaves.

    Summarised from Terry Pratchett et al, "The Science of Discworld", pp 307-308, discussing mass extinctions, and the surprisingly essential role they appear to have played in the evolutionary history.

  8. To clarify on An Improvement Upon Heisenberg's Uncertainty Theorem · · Score: 3, Informative
    The /. headline is rather misleading.

    Hall and Reginatto's paper does not supersede Heisenberg's uncertainty principle, nor does their paper change or challenge any of the fundamental results of quantum mechanics.

    To explain:

    Heisenberg's relation can be seen as an example of a (classical) result in Fourier theory about pairs of variables which are Fourier transforms of each other (for example time <> frequency), sometimes known as the bandwidth theorem. This is relevant because quantum wave mechanics asserts that wavefunction for a particle's momentum is essentially [a Constant times] the Fourier transform of the wavefunction of the particle's position.

    Why should there be this Fourier relationship between x and p ? (After all, in classical physics both position and momentum are point quantites, assumed to exist independently to infinite precision.) Well typically, the position taken is either that you've drawn a picture of some waves wiggling along according to the Schrodinger equation, and you say you believe in your picture; or it's because you're stating the relation as an axiomatic principle, [\hat{x},\hat{p}] = ih/2pi, which with some other axioms you then use to derive Schrodinger's equation.

    What Hall and Reginatto are really interested in is this: what other questions could you have set up, that would have led to the Schrodinger equation as a solution. (In statistics this approach is sometimes known as 'characterisation' of a distribution or evolution equation -- what "principles" might have caused it to come about).

    Here they show that the Schrodinger equation and the x <> p Fourier transform relationship are in some senses the most 'natural' outcome, if you start with the classical Lagrangian of the Hamilton-Jacobi equation for the evolution of a probability distribution of a particle, and add a new term which adds an extra uncertainty to the momentum at each possible point, proportional to the local Fisher information of the probability distribution for position (ie its local sharpness, more or less).

    This equation for an evolving probability distribution does not (necessarily) involve wavefunctions as physical entities; which may or may not make it a more useful and focussed way to think about what makes quantum mechanics "different".

    The authors caution that their approach does not attempt to provide a 'realistic' [ie mechanistic] model for where the extra momentum uncertainty comes from; any such attempt, they write, 'would require a whole new (and nonlocal) theory that goes beyond quantum mechanics'.

  9. Mod parent up (multiple-signed checksum repository on FBI Confirms Magic Lantern Existence · · Score: 2
    Sounds like a good idea to me.

    Many redundant copies, each signed by a different trusted 'good guy', for each checksum in the repository.

    At least the FBI would have to work that much harder before it could get all the signers nobbled (or trojaned)...

    ((Of course, we would still have to obtain trusted copies of the signers' public keys -- from a non-internet source presumably, magazine cover CDs perhaps ?))

  10. Meanwhile, UK plans to halve trial by jury on Anti-Civil Liberties Legislation Progresses · · Score: 5, Informative
    As part of a wider report into the future of the UK justice system published on Monday, Lord Justice Auld recommends removing the right of trial by jury in 50% of current cases.

    The right to trial by jury would be abolished in all instances where the sentence was likely to be less than two years. This would include most prosecutions under sec. 296 of the Copyrights Designs and Patents Act (the UK's DMCA), as well as serious reputation-destroying charges such as theft, assault and drug offences, where defendants can at the moment insist on jury trials. To prevent "perverse" decisions, Auld also recommends that judges should be allowed to ask juries specific menus of questions about the facts of the case instead of innocent-or-guilty verdicts, reserving the final decision for the judge themself.

    In a democratic system, the last ditch defence against a really bad law is that a jury can refuse to convict, in spite of the evidence, if they think that the prosecution is unfair or unreasonable. Cases thrown out by UK juries against the evidence in recent years include vandalism charges against GM crop protesters, official secrets charges against civil service whistleblowers and shoplifting charges against confused elderly people. Juries have also tended to be more critical of police evidence than judges and court officials; and to have had more relaxed views in obscenity and pornography cases.

    Specific comment: Independent, Guardian
    General reports: BBC, Times, Telegraph, Guardian, Independent
    (submitted to /. yro yesterday; rejected).

    And remember, as this week's NTK points out, bad UK law is often just version 0.1 for bad law in the US.

  11. Is it all about money ? on Ask A Tech-Savvy Lobbyist About The Politics Of Computing · · Score: 3, Interesting
    Lobbying is often portrayed as the filler cap where the money goes in to oil the political machine.

    It is dominated (according to the cartoon) by powerful rent-seeking corporations, spending big money to defend big interests, manipulating legislators who are desperate for ever more campaign contributions and ever more local feel-good stories.

    So:

    • Is it possible to lobby effectively without mega-resources ?
    • How often can legislators be persuaded to put their principles before their pocketbooks ?
  12. Top five issues ? on Ask A Tech-Savvy Lobbyist About The Politics Of Computing · · Score: 5, Interesting

    What would you say are the top five issues that *need* an effective lobbying effort at the moment ?

  13. SSH is a better battleground than PGP on News.com: Crypto Doesn't Kill - People Do · · Score: 3, Insightful
    I think you're both right.

    As far as I can see, *email* encryption really is what the general media and the politicians do think the argument is all about. Because so far only a small fringe minority use encrypted email, the pols think it will hardly be missed; and besides, the obsessive secrecy probably indicates that the users are up to no good anyway.

    The idea of *channel* encryption probably doesn't even cross their radar. But 'alienmole' is absolutely right: the most widespread and important use of encryption at the moment is *not* email; it is the use of ssh and friends to secure public channels. And the reason these are so important is obvious -- and probably much easier to explain to the public -- in these days of crackers and virus writers: you really don't want anyone to be able to break into your channel, and interfere with your remotely-controlled telescope or heart operation or hack into your corporate network or whatever.

    The case for SSH is much easier to make than the case for PGP, because of its demonstrable real-world importance. If we can move the debate towards channel security, away from email security, it will be much easier to win.

    But of course as soon as two people can ssh into the same box and talk to each other, the banning of any other uses of encryption starts to look pretty irrelevant.

  14. Re:Criminalization of Encryption on Philip Zimmermann and 'Guilt' Over PGP · · Score: 1
    Encrypted messages can be easily hidden inside image and sound files (a process known as steganography). Its not a simple problem since there are an infinite number of encoding schemes which can be used. Such algorithms are only limited by the human mind.

    Strangely enough I submitted an "Ask Slashdot" earlier this afternoon, on exactly this question: Just how good are steganography programs ?

    A paper by Neils Provos and Peter Honeyman of U. Michigan mentioned in the Register today explains why it is very easy it is to spot steganographic content in JPEGs from two of the most widely used programs, JSteg and JPHide (even though they couldn't find any on EBay).

  15. Re:Criminalization of Encryption on Philip Zimmermann and 'Guilt' Over PGP · · Score: 1
    Unlikely. A better response would be to increase the penalties under RIPA for not disclosing your encrpytion keys, to 20 years or so. That way, you have a targetted weapon to use against people who you genuinely believe are Really Bad.

    On the other hand:

    (i) Targeting takes investigative resources, and also prior information. A blanket ban may seem much simpler to some people, with no need for warrants and costly procedural work.

    (ii) There may be people out there who hate the idea of unbreakable encryption so much that they want to ban it just on principle, before it comes into general widespread consumer use (and very definitely before it leads to the widespread stream cyphering of IP telephony).

  16. Re:Criminalization of Encryption on Philip Zimmermann and 'Guilt' Over PGP · · Score: 1
    Nope, it cannot be enforced.
    You can easily send pgp/gpg encrypted email (though not authenticated) with false headers claiming to be someone else.

    You might fool the recipient, but would you fool the Carnivore equipment forced on your ISP or backbone provider ?

  17. Re:Criminalization of Encryption on Philip Zimmermann and 'Guilt' Over PGP · · Score: 1
    Not without making criminals of tens of millions of law-abiding users. I for one think that alone makes it unrealistic.

    Allowing the government to collect tens of millions of automated fines, just like speed cameras ?

  18. Criminalization of Encryption on Philip Zimmermann and 'Guilt' Over PGP · · Score: 5, Interesting

    The idea is seriously being canvassed in the UK, of making it a criminal offence to send strongly encrypted material by email, or to put it up on a web page. Could such a law be enforced ?

  19. Does the administration *know* what sort of war ? on A New Kind of War · · Score: 2
    Has the administration even decided what sort of war it is talking about ?

    There seemed to be a number of different viewpoints coming out of Washington this weekend, each pointing in a different direction.

    I found this pull-together and analysis (originally written for the Christian Science Monitor) over at Nando.net . I strongly recommend the full article -- I just hope that she is right in her conclusions, that voices for extreme carefulness are prevailing, in deciding the US response.

    ANALYSIS: U.S. calculates a war with little room for error
    ...
    The upshot is that, behind the rhetoric about ridding the world of "evildoers," the Bush administration must walk a tightrope, balancing the imperative of fighting terrorists with the risk of unleashing new threats, these experts say. Key to staying on the tightrope, they suggest, are a meticulous strategy, prudent planning and a crystal-clear mission.

    "There is no margin for error," said Ken Duberstein, a former White House chief of staff, in a television interview Sunday.

    Public statements over the past week by top American officials suggest that the Bush administration is engaged in an intense internal debate over exactly what the right strategy should be.
    ...

    PS (OT) Does anyone still use Nando ? It must have been just about the first mainstream news website on the net, and still (IMHO) has an excellent balance of wire stories. But it seemed hardly slashdotted at all a week ago. Does anyone still go there ?
  20. Re:Outline of a new war on A New Kind of War · · Score: 2
    We're fighting an enemy that doesn't have a physical location or capital assets to destroy. They indoctrinate their children to hate us. So what do we do? Fight with propaganda and turn the tide of the people away from hate for us. Drop leaflets, fund infrastructure, educate, bring CNN, bring the internet, feed them!

    Arguably this is why WW2 was truly a victory; whereas WW1 (for all the military success) was not.

    Survival and then victory in 1945 were only the first stage. The lasting victory was to persuade the Japanese and German peoples to reject, even to condemn the past, and to refocus on a positive future.

    The imperative in the present 'war' isn't to reduce a few military training areas to rubble in Afghanistan. That isn't even the main battle. The real war the West must win is to change minds. It will be much harder, and will take much longer. I only hope we can succeed.

  21. "Echelon warned of attacks" - German intelligence on More Links And Updates On Terrorist Attacks · · Score: 3, Interesting
    According to the Frankfurter Allgemeine Zeitung, one of the most famously serious newspapers in Germany, warning singnals about the attck were picked up at least three months ago by the Echelon surveillance network.

    Telecom Paper (Holland) gives this English-language summary:

    Echelon gave authorities warning of attacks

    Monday September 17, 2001.

    U.S. and Israeli intelligence agencies received warning signals at least three months ago that Middle Eastern terrorists were planning to hijack commercial aircraft to use as weapons to attack important symbols of American and Israeli culture, according to a story in Germany's daily Frankfurter Allgemeine Zeitung (FAZ). The FAZ, quoting unnamed German intelligence sources, said that the Echelon spy network was being used to collect information about the terrorist threats, and that U.K. intelligence services apparently also had advance warning. Within the American intelligence community, the warnings were taken seriously and surveillance intensified, the FAZ said. However, there was disagreement on how such terrorist attacks could be prevented, the newspaper said. Echelon is said to be a vast information collection system capable of monitoring all the electronic communications in the world. It is thought to be operated by the U.S., the U.K., Canada, Australia and New Zealand. No government agency has ever confirmed or denied its existence. However, an EU committee that investigated Echelon for more than a year just last week reported its belief that the system does exist.

  22. "Laws will be changed" - Ashcroft on BBC: AOL, Earthlink Are 'Cooperating' With FBI · · Score: 3, Interesting
    If we all used GPG for our email transmissions, this wouldn't be a problem, would it? That is until a few months goes by and a new amendment to the constitution prohibits encryption tools of any kind... Think I'm crazy? We'll see.

    Just up on Ananova:
    http://www.ananova.com/news/story/sm_400036.html?m enu=news.usterrorattacks

    US Attorney General says attacks will mean changes in law

    US Attorney General John Ashcroft says several US laws will be changed as a result off the terrorist attacks.

    He says laws governing phone-tapping are being examined and will be changed to make surveillance easier.

    He says the appearance of mobile phones has made it more difficult to keep track of terrorists.

    "It's clear to me we need to upgrade and strengthen a number of laws in the US," he says.

    Steps have already been taken by Congress to address this, he told reporters.

    Story filed: 17:32 Sunday 16th September 2001

  23. Bin Laden's people "using cybercafes in Pakistan" on BBC: AOL, Earthlink Are 'Cooperating' With FBI · · Score: 5, Informative
    Interesting piece in today's Sunday Telegraph on how Bin Laden is set up in Afghanistan, written by one of the BBC's most senior reporters, John Simpson, from the border between Afghanistan and Pakistan.

    The full article is at
    http://portal.telegraph.co.uk/news/main.jhtml?xml= /news/2001/09/16/wbin116.xml

    Extract:

    Forget those earnest statements from Taliban spokesmen that bin Laden is under house arrest in Kandahar or that his communications equipment has been confiscated. These things are said to deceive the simple-minded, and to distance the Taliban from his activities.
    ...

    Bin Laden has one of the most sophisticated communications systems in the region. A communications vehicle is stationed at a distance from him, and his calls are routed through it. That way, if they are intercepted, he won't be hit by some smart weapon fired from a distance.

    But he makes few calls anyway; instead, when he wants to speak to people in Pakistan, he sends his Afghan spokesman quietly across the border. No amount of international eavesdropping can detect that.

    Other bin Laden agents make for the internet cafes that have sprung up in the Pakistani border town of Peshawar. They use the most common service providers, all of them American, and refer to each other and to bin Laden himself by their first names. In the welter of e-mail traffic their messages go unnoticed. If approval for the World Trade Centre operation came from bin Laden, then this is how it would have been done.

  24. Someone mod this up (+5 funny) on Bobby Fischer Online? · · Score: 1

    Classic.

  25. This is where Autonomy started on Software Sorts Electronic Evidence · · Score: 2
    What is now Autonomy, the knowledge management company, started about ten years ago when Mike Lynch's PhD research was sponsored by the police in the UK, to find ways to scan the mass of witness statements that are gathered in a major incident enquiry (often inconsistent, with varying content and terminolgy), and to automatically identify important features and cross-reference them.

    From that original start, they then (allegedly) gained the interest of the intelligence services,and then the media companies and dot coms, to become the players they are today.