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Physicists Find Users Uninterested After 36 Hours

SuperGrads writes "Statistical physicists working in the US and Hungary have found that the number of people reading a particular news story on the web decreases with time by a power law rather than exponentially as was previously thought. The finding has implications for the study of information flow in social networks, marketing and web design."

36 of 141 comments (clear)

  1. In related news by lecithin · · Score: 5, Funny

    Users Find Physicists Uninteresting After 3.6 seconds.

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    It could be worse, it could be Monday.
    1. Re:In related news by JPribe · · Score: 5, Interesting

      Wow. It didn't even take that long.

      But seriously, I wonder if this will change ad placement for revenue models? If an ad gets a click on a story older than 36 hours, is it worth more? Hmm, I smell a patent in the works, too.

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    2. Re:In related news by The_Wilschon · · Score: 4, Funny

      Well, I Am A Physicist, and I certainly find YOU uninteresting!

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      wait... not that kind of sig.
  2. Old news by Percent+Man · · Score: 5, Funny

    Are we still talking about this?

  3. However ... by blowdart · · Score: 5, Funny

    The story will get posted again on slashdot 37 hours later.

  4. maybe because it's not "news" anymore? by holden+caufield · · Score: 4, Interesting

    I'm wondering if these same researches tried to define what their subjects defined as "news"? If something was newsworthy, I'm guessing they likely found out about it over time. Maybe the people didn't read it because they were informed from other sources?

    Sounds like a bit of a flawed evaluation to me.

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    1. Re:maybe because it's not "news" anymore? by truthsearch · · Score: 3, Insightful

      It might also be relevant that this study was done only on a Hungarian news site. It's possible there would be different results in other countries due to cultural differences and the number of available news sources.

    2. Re:maybe because it's not "news" anymore? by The_Wilschon · · Score: 4, Informative

      The "news" in this story is not that people become disinterested in a story, but that the rate at which they become disinterested is quite different from what was expected.

      Furthermore, the study was not done by taking people and finding out how quickly they became disinterested in one story or another. A quick glance at the summary informs us that the subject of the study was the number of people reading a news story (more likely downloading the story) at a given time. That this number decreases with time is obvious. However, it was expected that the decrease would follow an exponential curve, whereas the experiment showed a power law curve instead.

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      SIGSEGV caught, terminating

      wait... not that kind of sig.
    3. Re:maybe because it's not "news" anymore? by yfnET · · Score: 3, Informative

      To prove the point, they actually did such a reversal in the case of telephone-queue waiting times. Traditionally, these have been assumed to follow a Poisson distribution, but some recent research suggests they actually follow a power law. Analysing the participants’ responses suggests that a power law, indeed, it is.

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      Science & Technology / Psychology

      Bayes rules
      Jan 5th 2006
      From The Economist print edition

      A once-neglected statistical technique may help to explain how the mind works

      IMAGE

      SCIENCE, being a human activity, is not immune to fashion. For example, one of the first mathematicians to study the subject of probability theory was an English clergyman called Thomas Bayes, who was born in 1702 and died in 1761. His ideas about the prediction of future events from one or two examples were popular for a while, and have never been fundamentally challenged. But they were eventually overwhelmed by those of the “frequentist” school, which developed the methods based on sampling from a large population that now dominate the field and are used to predict things as diverse as the outcomes of elections and preferences for chocolate bars.

      Recently, however, Bayes’s ideas have made a comeback among computer scientists trying to design software with human-like intelligence. Bayesian reasoning now lies at the heart of leading internet search engines and automated “help wizards”. That has prompted some psychologists to ask if the human brain itself might be a Bayesian-reasoning machine. They suggest that the Bayesian capacity to draw strong inferences from sparse data could be crucial to the way the mind perceives the world, plans actions, comprehends and learns language, reasons from correlation to causation, and even understands the goals and beliefs of other minds.

      These researchers have conducted laboratory experiments that convince them they are on the right track, but only recently have they begun to look at whether the brain copes with everyday judgments in the real world in a Bayesian manner. In research to be published later this year in Psychological Science, Thomas Griffiths of Brown University in Rhode Island and Joshua Tenenbaum of the Massachusetts Institute of Technology put the idea of a Bayesian brain to a quotidian test. They found that it passes with flying colours.

      Prior assumptions
      The key to successful Bayesian reasoning is not in having an extensive, unbiased sample, which is the eternal worry of frequentists, but rather in having an appropriate “prior”, as it is known to the cognoscenti. This prior is an assumption about the way the world works—in essence, a hypothesis about reality—that can be expressed as a mathematical probability distribution of the frequency with which events of a particular magnitude happen.

      The best known of these probability distributions is the “normal”, or Gaussian distribution. This has a curve similar to the cross-section of a bell, with events of middling magnitude being common, and those of small and large magnitude rare, so it is sometimes known by a third name, the bell-curve distribution. But there are also the Poisson distribution, the Erlang distribution, the power-law distribution and many even weirder ones that are not the consequence of simple mathematical equations (or, at least, of equations that mathematicians regard as simple).

      With the correct prior, even a single piece of data can be used to make meaningful Bayesian predictions. By contrast frequentists, though they deal with the same probability distributions as Bayesians, make fewer prior assumptions about the distribution that applies in any particular situation. Frequentism is thus a more robust approach, but one that is not well suited to

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    4. Re:maybe because it's not "news" anymore? by twistedsymphony · · Score: 2, Insightful
      I'm wondering if these same researches tried to define what their subjects defined as "news"? If something was newsworthy, I'm guessing they likely found out about it over time. Maybe the people didn't read it because they were informed from other sources?
      Maybe that's exactly right? maybe 36 hours is the saturation point where someone is most likely to have already seen it elsewhere... After-all if YOU haven't seent it yet, it's still news to YOU.
    5. Re:maybe because it's not "news" anymore? by Larus · · Score: 2, Interesting

      TFA mentions a 'typical news website'. Exactly what is a typical news website? Are we talking NYTimes and WashingtonPost that covers a broad spectrum, or a smorgasbord news bulletin like /. and Digg?

    6. Re:maybe because it's not "news" anymore? by m874t232 · · Score: 2, Interesting

      The "news" in this story is not that people become disinterested in a story, but that the rate at which they become disinterested is quite different from what was expected.

      "Expected" by who? Anybody reasonably familiar with statistics wouldn't assume that this decay is exponential because there is absolutely no reason to make that assumption; none of the models that commonly lead to exponential decay apply in this case.

      Even though this guy happens to use the web, these kinds of problems aren't anything new. If you put a statistician on it, he'd either use an empirical model for the rate, or model it with a power law.

      I think this "expectation" gives us a lot more about the unfamiliarity of the author with statistics than about the real world.

  5. Re:First post by Luctius · · Score: 5, Funny

    Please reread your own sig.

  6. Impulse function by courtarro · · Score: 3, Funny

    Users losing interest in this particular news story follow an impulse function.

    1. Re:Impulse function by m0nstr42 · · Score: 3, Funny

      This is "interesting"? It should just be "funny"!

      I mean, EVERYONE knows what an impulse function is, right?

      Right?

      It's so very lonely here.

      P.S. It's not really a function. It's a distribution, measure, functional, possibly some other things, but not a function.

      Yes, very lonely.

  7. Another massive triumph for statistical physicists by Rob+T+Firefly · · Score: 5, Funny

    Actually, nobody cares about this sort of thing, and these so-called "statistical physicists" would all be cleaning gutters for a living right now.. except the guy from HR is too terrified to go downstairs and fire them. The last time he tried, they somehow irrevocably proved to him that not only was it statistically impossible that he had arrived to give them their pink slips, but they also proved his trousers, eyebrows, and cat out of existence with nothing more than a slide rule and a whiteboard.

  8. Possible other causes? by Todd+Knarr · · Score: 4, Insightful

    One has to wonder how the site's story policy affects the drop-off. That is, is the drop-off because users are uninterested or not reading, or is it because after that time the story drops off the main pages and becomes hard to find to read?

  9. BREAKING NEWS by 27,000 · · Score: 3, Insightful

    PHYSICISTS REPORT ARTICLES NOT ON FRONT PAGE READ LESS

    ALSO NOTE THAT SITES HAVE FINITE NUMBERS OF USERS

    And nothing about 'uninterested users'. This implies that, well, a reader is not likely to read an article more than once. Shocking, much unlike the answer to the question who is funding these people?

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    My problem with spontaneous human combustion is that never seems to happen to the "right" people.
  10. Re:Linked by truthsearch · · Score: 2, Funny

    I guess you disagree with the author. Otherwise you would have provided a link...

  11. Politics by Raleel · · Score: 2, Interesting

    This is why badnews in politics is always released late on friday. By Monday, everyone has ignored it.

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    -- Who is the bigger fool? The fool or the fool who follows him? --
  12. Methodological issues? by gilroy · · Score: 5, Interesting
    I've read the linked article but not the actual Phys Rev paper, so I'm likely blowing smoke but...

    • The "news cycle" is 24 hours, due to historical roots in daily newspapers (augmented by the evening news, etc.) Assume for the moment that people stay interested in a news story. After a day, if the story is ongoing, the original article is likely to be replaced by an update. Real-life example: Over the weekend, the NY Times Science section had these stories in a row: "Shuttle astronauts complete spacewalk", "shuttle astronauts inspect tiles", "shuttle Discovery meets space station", "shuttle Discovery set for launch". (paraphrased) Clearly, the first story in the list is the most recent and, were I looking for news on the Discovery, I'd probably click that one. Even if I really liked the Times' coverage of the rendez-vous, I'm not likely to read that article again if a new one has been posted. Does that mean I've "lost interest" in the shuttle?
    • The results seem drawn from traffic at a particular Hungarian portal and might not have any generalized relevance.
    • Ease of navigation seems important but not addressed. If stories "fall off" the homepage after 36 hours, it would make it look like people were less interested. (Or, really, the fact that some stories are highlit on the front page makes it look like people are more interested than they really are.)

  13. Heh. by wfberg · · Score: 5, Funny

    Good luck in explaining the spike in traffic 3 full days after the article was posted.

    Suckers!

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    SCO employee? Check out the bounty
  14. Three things to consider by WillAffleckUW · · Score: 2, Interesting

    1. If you go on vacation, and spend the usual two to four weeks relaxing, ignoring all the news except maybe browsing the headlines one day a week, as I frequently do, does the news not have equal importance? In other words, perhaps most of what we call "news" is temporary by nature, and grows less relevant with the passage of time. Please note this doesn't relate to medical/health/science news, as I've read many scientific papers from years ago that are just as relevant today as they were then. Also, for those in the US and Japan, yes, the world understands you don't get much vacation, but that's your problem.

    2. How much of the news is what we call 'entertainment' news? How much is 'sports' news? Such news quickly ceases to have relevance, other than to fans of both media.

    3. Perhaps the lack of investigative journalism, the lack of crafting of news into stories that take days to write, has led to the current situation where news quickly becomes staledated? I've read many an old copy of The New Yorker, and most of the stories about news are still relevant today, maybe one-fourth becoming less so due to the passage of time. Consider the skill and the medium used.

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  15. ISR... by MachDelta · · Score: 2, Funny

    Let me guess. You're from Soviet Russia, yes?

  16. Physicists are not the best people.... by tobiathan · · Score: 2, Interesting

    ...to be studying this sort of thing. In any subject where the laws of Physics apply, physicists are very well suited to look at the data. Since humans are so prone to actions that defy any logic or reason, a behavioral psychologist would be better suited to have an opinion. Let's pose this question back to Steven Hawking.

  17. Re:Who Knew?!! by refriedchicken · · Score: 3, Funny
    "36 Hours is the exact age of a story before it drops from the bottom of slashdot's Main page."

    And is recycled back to the the top.

  18. Exponent? Power? by ch-chuck · · Score: 3, Insightful

    Color me ignorant, but I thought exponentials and powers were the same thing?
    Or are they talking about natural exp -vs- a higher order power, like 4 or 5?

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    try { do() || do_not(); } catch (JediException err) { yoda(err); }
    1. Re:Exponent? Power? by DaoudaW · · Score: 4, Informative

      The difference is whether the independent variable is the base or the exponent. A power function is something like f(x)=x^(.5) whereas an exponential function could be f(x)= (.5)^x.

  19. What about missing blond females? by toupsie · · Score: 2, Interesting

    Missing blond females seem to stay in the news a lot longer than 36 hours. Most of the advertising revenue of the cable news networks is based on blond female becoming missing. Fox News, CNN and MSNBC would be reduced to covering real news if it weren't for them. I wouldn't be surprised if most weren't missing due to a conspiracy of cable news producers preying on them. They all those news vans just sitting around.

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    Strange women lying in ponds distributing swords is no basis for a system of government.
  20. How is this physics? by nigham · · Score: 2, Insightful

    Physics is the science of nature, and I don't think human nature is included.

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    I don't want to read /. I want to go home and re-think my life.
  21. One slight problem... by pla · · Score: 2, Insightful
    Okay, folks - Since I have yet to see any non-humor comments on this topic, I'll break the ice. From TFA:
    Thanks to automatically assigned "cookies", the scientists were able to reconstruct the browsing history of about 250,000 visitors to the site over the course of a month.
    [... and ...]
    Although the average half-life varies for different types of sites, the decay laws identified are likely to be generic because they do not depend on content, but are manly determined by a user's visiting and browsing patterns.
    So, what do we see here?

    This trend depends on user browsing patterns rather than content, but also depends on users allowing cookies to live for not only longer than one browsing session, but for a full month.

    Thus, much like that classic problem of proving the external validity of any research done by a college psych department on their own undergrads (which usually results in 80-90% female and at least half freshman participants), this study has a pretty glaring flaw - It only really says anything about MSIE users (and even then, only MSIE users dumb enough not to use some form of cookie management) rather than users in general. While that almost certainly includes the majority of visitors to many sites, it doesn't safely extend to the larger population of all web surfers.



    Additionally, I would point out one more glaring source of error... It fails to normalize each unit of time against the remaining base of users - So, for example, if 90% of the regular visitors to a site see an article within an hour of posting, that leaves only 10% (plus the negligibly-small number that re-read the same article over and over, except on Slashdot where you can use FP refreshes as a solid measure of workday boredom). That, IMO, says far more about how long the typical (MSIE-qualified as above) user can go without a news fix, rather than how long an article remains interesting.
  22. We Just Killed Their Theory by Anonymous Coward · · Score: 4, Funny

    I can see these physicists really scratching their heads when the article gets slashdotted 72 hours after the published date (July 7).

  23. Half Life = Exponential! by CarbonRing · · Score: 2, Informative

    Any rate that decays continuously with a half-life can be described by a function of the form C*e^(-kt) where t is time, C is the initial rate (at t = 0), and the constant k = ln(2)/(half life), with half-life measured in the same units as time.

    A power law relationship is something of the form y = A*t^k, which cannot be used to model a rate with a half life, since the time to reduce the rate by half depends on where you start, and increases as time increases.

    Also any exponential function (with negative k) eventually decays faster than any power law function. The power law can start decaying faster, but since the half life will increase with time, the exponential function with a constant half-life will always eventually get under it. (L'Hospital's rule is your friend.)

    So to say that something that can be described with a half life follows a power law rather than a exponential function, and decays faster than an exponential function, indicates a complete ignorance of the methematical terms. This also calls into question the validity of everything else the article says.

  24. Summary misstates article by Nurf · · Score: 3, Insightful

    If you read the article, it says the distribution of half-lives of stories decreases as a power law, not that hit rates on stories decrease as a power law.

    Half lives are a measurement of exponential decay. Individual stories still decrease in hits exponentially over time. If you look at lots of stories, the decays are distributed according to a power law.

    The article directly contradicts the Slasdot summary.

    Hits on stories do decrease exponentially.

    I am stunned that I am the only one so far who seems to have picked up on this. Did anyone actually read the article, or did they just read into it what they were told they would see?

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  25. rediscovering the wheel by idlake · · Score: 2, Interesting

    How interest in news items evolves over time, how it depends on communication, links, and recommendations, has been the subject of research for decades. E-commerce sites use detailed models of this in order to determine when to remove items from the front page.

    It is true that many people use exponential decay models, but that's not because they don't know any better, it's because exponential decay is computationally simple and works well enough. It's like using a linear approximation to a non-linear problem.

    I think it's pretty telling that Barabási is publishing this in physics journals, not in statistics or web-related publications. This may be news to physicists, but it isn't news to anybody who actually works in the field and knows their stuff. The reviewers at Phys. rev. simply aren't qualified to determine whether this kind of work is novel and correct.

  26. Duh. by StikyPad · · Score: 3, Funny

    Current tags: boring, slownewsday, yawn, uninteresting and duh.

    Put another way: Slashdot -- Now with 20% real nerds!