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Scientists Define Murphy's Law

Posted by CmdrTaco on Sun Oct 10, 2004 11:13 AM
from the brillaint-or-pathetic dept.
Jesrad writes "A mathematician, a psychologist and an economist commissioned by British Gas have finally put into mathematical terms what we all knew: that things don't just go wrong, they do so at the most annoying moment.The formula, ((U+C+I) x (10-S))/20 x A x 1/(1-sin(F/10)), indicates that to beat Murphy's Law (a.k.a. Sod's Law) you need to change one of the parameter: U for urgency, C for complexity, I for importance, S for skill, F for frequency and A for aggravation. Or in the researchers' own words: "If you haven't got the skill to do something important, leave it alone. If something is urgent or complex, find a simple way to do it. If something going wrong will particularly aggravate you, make certain you know how to do it." Don't you like it when maths back up common sense ?"
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  • by Anonymous Coward on Sunday October 10 2004, @11:14AM (#10486250)
    Women are evil [wisc.edu].
    • by pjt33 (739471) on Sunday October 10 2004, @12:09PM (#10486576)
      A mathematician, a psychologist and an economist
      is clearly the lead into something like
      were on a train travelling from Glasgow to Edinburgh when they saw a sheep. The psychologist said, "Look: Scottish sheep are black!" The economist replied, "Well, we can at least say that some Scottish sheep are black." At this the mathematician spoke up: "There exists at least one sheep in Scotland at least one side of which is black."
        • by swillden (191260) * <shawn-ds@willden.org> on Monday October 11 2004, @12:30AM (#10490421) Homepage Journal

          The hermetic nature of basic math is from a limitation of mathematicians, us, rather than math itself.

          You've got it backwards. This joke doesn't illustrate a weakness of mathematical thinking, it illustrates a key strength. Mathematics is all about precise, rigorous reasoning, and that's what makes it both useful and beautiful. Fuzzy thinking that makes unnecessary assumptions limits the thought processes and closes off interesting lines of investigation. What if the the sheep *was* black only on one side? What might that imply? Or is it possible to demonstrate that a sheep that is black on one side must therefore be entirely black? Avoiding assumptions is a good thing, a way to free your mind, not to limit it. Even better is to go ahead and make assumptions, with the clear understanding of what you are assuming and see where it leads. You can even make assumptions that are counter to observed facts and see where that goes (e.g. non-Euclidean geometry -- which turns out to be highly useful in the real world -- was created in the midst of an attempt to demonstrate that Euclid's parallel postulate must be "true" because to assume otherwise leads to contradictions -- only it doesn't).

          I'm a mathematician* and I think that joke spreads a valuable and important meme. Don't counter it, clarify it.

          *Speaking of precision: Perhaps I shouldn't call myself a mathematician. I have a BS in Mathematics (pure, not applied or any somesuch) which doesn't so much make me a mathematician as someone who once wanted to be a mathematician. I still occasionally study a little math for fun.

  • Er... (Score:5, Insightful)

    by 26199 (577806) on Sunday October 10 2004, @11:15AM (#10486262) Homepage

    Maths doesn't work like that. Writing something down as a formula doesn't automatically tell you something new or prove something.

    It sounds like they're trying to describe how things can go wrong with a formula. That's nice, but it's just their opinion.

    • Re:Er... (Score:3, Insightful)

      by grasshoppa (657393)
      Maths doesn't work like that. Writing something down as a formula doesn't automatically tell you something new or prove something.

      It sounds like they're trying to describe how things can go wrong with a formula. That's nice, but it's just their opinion.


      Christ, you must be a blast at parties.

      You know that was a joke, right? Right?
      • by SmallFurryCreature (593017) on Sunday October 10 2004, @12:18PM (#10486626) Journal
        Apparantly not and many others like him don't get it either. Read the comments below and weep for what once was /. home of the nerd/geek who understood math jokes.

        It is a joke people. No need to question who did it or what school they went to or discuss the merits of trying to explain the nature of probability in a formula.

        A FUCKING JOKE. If you need it simpler it is like the old "You can have it fast, good or cheap. Pick two" but with more braces.

        Seriously read the comments. A lot just don't seem to get it at all. Those few who did. Thank god. All hope is not lost. To those who didn't go I recommend suicide. Make the world a happier place.

      • Re:Er... (Score:3, Interesting)

        by Mac Degger (576336)
        This, however, isn't:

        http://www.matrix-evolutions.com/

        Despite the URL, there is some serious and, as far as I can tell, correct math proving Bush wrong. Just skip to the last paragraphs to see how mathematics defines 'significant' :)
        • Re:Er... (Score:3, Interesting)

          by Uggy (99326)
          I concur, this is exactly how military risk assessment worksheets work. I kind of like this new version a little better though. PHB aggravation factor is useful.

          It basically boils down to how often do you do a thing? (frequency). How bad can the worst failure be? (importance).
          Mitigating factors (skill, urgency). Which basically gives you what British Gas came up with.

    • equals (Score:3, Insightful)

      by Doc Ruby (173196)
      No, mathematics is exactly that: a description of the phenmoena. The "laws" we're always talking about are just reasonable expectations of consistent phenomena, phrased to exclude irrelevant factors and products, while describing the relationships between the phenomena actually involved. "The map is not the territory". Math is the map. Observations are facts, and formulae are strict, testable interpretations of patterns among facts. Opinions are based on beliefs and faith - so one can have an opinion about
      • Re:equals (Score:5, Funny)

        by miskatonic alumnus (668722) on Sunday October 10 2004, @11:47AM (#10486447)
        I don't see how this particular formula is testable. How does one quantify urgency or aggravation in order to test the model? Methinks they left out the most important variable, B for Bullshit, measured in metric tons. ;)
        • Re:equals (Score:5, Interesting)

          by Doc Ruby (173196) on Sunday October 10 2004, @11:57AM (#10486511) Homepage Journal
          Urgency and aggravation are measured on their own relative scale, as percentages of unity (0.0->1.0). Urgency is asymptotic to the deadline, and aggravation is a combinatoric of other factors, possibly even keyed to the multidimensional gravity vector of the iotas of info. Schneidics postulates that just as space = gravity = matter = energy, so does energy = info. We're all describing schneidodynamics, detailing mechanisms that can be engineered into applications. Current mathematical tools are mostly targeting applications in grant engineering.
          • Re:equals (Score:4, Funny)

            by dougmc (70836) <dougmc+slashdot@frenzied.us> on Sunday October 10 2004, @12:02PM (#10486533) Homepage
            possibly even keyed to the multidimensional gravity vector of the iotas of info.
            Impressive. Now just re-route the plasma through the deflector dish and create a static warp field, and we can make things just like they were 50 minutes ago and wrap this episode up!
        • Re:equals (Score:5, Funny)

          by aonifer (64619) on Sunday October 10 2004, @06:37PM (#10488746)
          How does one quantify urgency

          Fraction of bladder. 0 = bladder empty, no urgency. 1 = bladder full. Hoo boy, that's urgent.
      • Re:equals (Score:3, Insightful)

        by Esben (553245)
        You mix math with other sciences, like physics. Physics is indeed like what you descripe. Math isn't. Math is about starting from some simple axioms and prove all the rest with logic, not observations.
          • Re:equals (Score:5, Informative)

            by Coryoth (254751) on Sunday October 10 2004, @12:13PM (#10486593) Homepage Journal
            Those axioms are observations. One important observation, one of two axioms underpinning all of math (and therefore science), is "consistency". The other is falsifiability, that only statements that can be proven false are scientific - the rest are metaphysical. Math such as "all triangles are composed of three interior angles totaling 180 degrees" is an observation, that is supported by theories and constructions. Physics applies math by interpreting the mathematical relationships in observed phenomena.

            I suggest you go and read some Bertrand Russell on philisophy of mathematics. Mathematics isn't based on observation at all. It's based on what axioms you choose to start with and using deductive logic from there - and you would be very surprised about how basic and not based on observation the funcamental axioms of mathematics are, presuming you bother to look at works that build up math from as small a foundation as possible. On that front, I would suggest you look at Principia Mathematica by Russell and Whitehead, which is pretty much the book on purest mathematical foundations.

            Jedidiah.
            • Re:equals (Score:3, Interesting)

              by Doc Ruby (173196)
              Well, I've read (through) both the Principia, and various Russell papers. I'm even going out to the New York Public Library to look at an original copy, as I've also looked at an original copy of Einstein's "relativity" and "photoelectric effect" papers. Where do you think these axioms come from? Observation, experience. I recommend Kant's _Philosophy of Pure Reason_, and his examinations of the "a posteriori / synthetic" category of reason. Of course, mentation (even German ;) doesn't fit neatly into a box
              • Re:equals (Score:4, Insightful)

                by Coryoth (254751) on Sunday October 10 2004, @01:48PM (#10487128) Homepage Journal
                If your going to haul Kant in then we're gettign to the level where everything we think is inescapably derived from observation. Mathematics is about as cleanly separated from that as possible. As to F=ma - that's not especially mathematical, it's physics, and yes, that's purely observational. On the other hand the fundamental theorem of calculus has considerably less to do with observation (presuming of course that we're building to it from Russell style defintions and his very limited set of axioms).

                I'm not trying to argue the pointfulness of the formula here given, I'm rather trying to stand up for the fact that mathematics, unlike physics for example, goes very much further to separate itself from "depending on observation". There are plenty concepts in mathematics (p-adic numbers, non-Hausdorff spaces, projective geometry) that run completely counter to anything observable.

                Jedidiah.
                • Re:equals (Score:3, Funny)

                  by Doc Ruby (173196)
                  I'd prefer to see it in terms of probabilistic unity, a decimal fraction. Then we can plug it into a good hot cup of tea, and blink across the multiverse. Trillian, I'm coming!
          • Re:equals (Score:5, Insightful)

            by JRaven (720) on Sunday October 10 2004, @12:37PM (#10486720)

            Those axioms are observations.


            No, those axioms are just the assumptions that a mathematician made. They don't have anything to do with reality, or the things we observe there. Every theorem has hypotheses and a conclusion; writing every one of those hypotheses every time you make a statement gets old, so you declare some things to be true before you get started.


            One important observation, one of two axioms underpinning all of math (and therefore science), is "consistency". The other is falsifiability, that only statements that can be proven false are scientific - the rest are metaphysical.


            The notion of consistency that troubles logicians is a matter of axioms -- it is merely a matter of whether there is a statement such that it and its negation follow from the axioms. Nothing to do with reality. As for "falsifiability", that has absolutely nothing to do with mathematics. Things are proven to be absolutely true in mathematics all the time.


            Math such as "all triangles are composed of three interior angles totaling 180 degrees" is an observation.


            No.

            I feel I must repeat: No.

            That the sum of the angles in a triangle is 180 degrees is a consequence of the axioms. It is most definitely not an observation, since it isn't actually true in the real world (though it is very close to what you might measure).

            The statement about angles is a consequence of Euclidean geometry. Work in a different geometry (ie non-flat, like spherical or hyperbolic geometry) and the formula for the sum of the angles is very different.
    • Re:Er... (Score:3, Insightful)

      by Tablizer (95088)
      Maths doesn't work like that. Writing something down as a formula doesn't automatically tell you something new or prove something.

      Score = 0
    • Re:Er... (Score:5, Funny)

      by Coryoth (254751) on Sunday October 10 2004, @11:51AM (#10486480) Homepage Journal
      The biggest dilemma is that this formula is just not testable. Clearly any test would be very Important and have to be carried out Frequently, and a test that covers all the situations to which Murphy's law might apply is clearly going to have to be Complex. So plugging all of that in, we see that, even if the formula is correct, all your attempts to verfiy it are doomed to failure!

      Jedidiah.
  • by barcodez (580516) on Sunday October 10 2004, @11:15AM (#10486266)
    Jesrad writes "A mathematician, a psychologist and an economist commissioned by British Gas have finally put into mathematical terms what we all knew: that things don't just go wrong, they do so at the most anno.... 503 service unavailable
  • Ugh (Score:5, Funny)

    by mrjah (574093) on Sunday October 10 2004, @11:16AM (#10486272)
    Quick, somebody start arguing about probability!
  • by product byproduct (628318) on Sunday October 10 2004, @11:20AM (#10486294)
    Better avoid a frequency of exactly 5*Pi.
    • Explanation (Score:5, Insightful)

      by herrvinny (698679) on Sunday October 10 2004, @12:12PM (#10486588)
      ((U+C+I) x (10-S))/20 x A x 1/(1-sin(F/10))

      The parent is noting that if you plug in 5*(pi) into F, you get sin(5*(pi)/10), which equals sin((pi)/2), which equals 1. The problem occurs when you evaluate this part: 1/(1-sin(F/10)), because you get 1/(1-1), which is 1/0, and division by 0 is prohibited.
  • by kb9vcr (127764) on Sunday October 10 2004, @11:23AM (#10486317)
    "things don't just go wrong, they do so at the most annoying moment"

    That's because, when things go wrong, it becomes the most annoying moment. My dishwaster just starting leaking all over the floor btw. Damn you murphy!
  • by pair-a-noyd (594371) on Sunday October 10 2004, @11:26AM (#10486329)
    Bumper sticker for me!

    ((U+C+I) x (10-S))/20 x A x 1/(1-sin(F/10))

    Yeah baby! Learn it, live it, love it!

    Actually, this formula is my life story in a nutshell.....
  • IT'S A JOKE! (Score:5, Informative)

    by grasshoppa (657393) <skennedy@tpno-c o . o rg> on Sunday October 10 2004, @11:26AM (#10486335) Homepage
    Notice the foot? It's supposed to be a somewhat humorous little blurb about something silly.

    What a fun crowd we've got around here on Sunday...
  • by Malor (3658) on Sunday October 10 2004, @11:30AM (#10486357) Journal
    Since, after all, they included a sin() call. As everyone knows, it's not real math unless it includes a trigonometric function. And lots of parens. Gotta have lots of those.

    Shame they didn't work in some of those cool Greek characters, though.
  • I usually cut Slashdot editorial some slack, but this is over the top. It's just a link to a tedious example of bad journalism as it stands. It should not have been posted as it stands. There's nothing to discuss.

    Experts at British Gas indeed. Why? How? No one is even telling us the quantity that is being calculated in this dubious formula.

    If you don't know, guys, kindly don't pass it on. So far it's just noise. Here's a slightly better link [scotsman.com], but still not, in my opinion, enough to bother with.

    • My bad, the news.com.au story dropped the last paragraph of the original story [sbs.com.au]:

      The equation has seven steps to forecasting a potential Murphy's Law moment, so you can work out which factors you need to change to avoid it:

      1. Rate the urgency, importance and complexity on a scale of one to nine and add the three figures together.
      2. Rate from one to nine how skilled you are at the task, then subtract this from 10.
      3. Multiply answers to 1 and 2 and divide by 20.
      4. Rate from one to nine how frequently you per
  • by Anonymous Coward on Sunday October 10 2004, @11:34AM (#10486379)
    And from today's joke at thehun.com [thehun.com] (link not work safe!!) ...

    From a strictly mathematical viewpoint it goes like this:

    What makes 100%?

    What does it mean to give MORE than 100%?

    Ever wonder about these people who say they are giving more than 100%?

    We have all been to these meetings where someone wants you to give over 100%

    How about achieving 103%? What makes up 100% in life?

    Here's a little mathematical formula that might help you answer these question.

    If:

    A B C D E F G H I J K L M N O P Q R S T U V W X Y Z is represented as:

    1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26.

    Then:

    H A R D W O R K

    8+18+4+23+15+18+11 = 98%

    K N O W L E D G E

    11+14+15+23+12+5+4+7+5 = 96%

    But:

    A T T I T U D E

    1+20+20++9+20+21+4+5 = 100%

    And:

    B U L L S H I T

    2+21+12+12+19+8+9+20 = 103%

    AND, Look how far ass kissing will take you.

    A S S K I S S I N G

    1+19+19+11+9+19+19+9+14+7 = 118%

    So, one can conclude with mathematical certainty that whilst hard work and knowledge will get you close, and attitude will get you there, it's the bullshit and ass kissing that will put you over the top.
  • by nels_tomlinson (106413) on Sunday October 10 2004, @11:46AM (#10486444) Homepage
    ((U+C+I) x (10-S))/20 x A x 1/(1-sin(F/10))

    So, when we're trying to estimate the parameters, we take logs and get:

    log(U+C+I) + log(10-S) - log20 + logA - log(1-sin(F/10))

    That means that we can estimate the effects of skill, aggravation and frequency separately, but the effects of urgency, complexity and importance can't be separated from one another.

    I'm pretty sure there's some deep, philosophical meaning to that.

  • Scientific Humor (Score:3, Interesting)

    by karlandtanya (601084) on Sunday October 10 2004, @11:47AM (#10486451)
    ((U+C+I) x (10-S))/20 x A x 1/(1-sin(F/10))


    is what? The number of times per week something will go wrong? A probability function describing the frustration field in the vicinity of a piece of hardware? The length of the scientist's nose?


    Where's the equals sign? Or comparison operator? Where's the other half of the equation?


    It's cute that somebody's multiplied a bunch of parameters. But they haven't said (mathematically) what that means.


    Murphy's law is a humorous observation at man's frustration with the universe. A mathematical descrption of Murphy's law would be scientific humor.


    What was reported by NEWS.com.au (and repeated by /.) is not scientific humor. It is, instead, meaningless crap.

  • by Baldrson (78598) on Sunday October 10 2004, @11:56AM (#10486509) Homepage Journal
    Project psychologist Dr David Lewis said... "So, if you haven't got the skill to do something important, leave it alone. If something is urgent or complex, find a simple way to do it. If something going wrong will particularly aggravate you, make certain you know how to do it."

    When asked why so many of his psychotherapy patients commit suicide, Dr. Lewis went on to say, "You're implying something went wrong. They would have become serial murderers or child rapists if I handn't helped them. Are you saying I should be aggravated over the outcome of having saved lives while protecting little children from molestation? If I didn't have the skills I have, you might not be standing here asking such questions, you Wanker."

  • Close (Score:5, Informative)

    by Minwee (522556) <dcr@neverwhen.org> on Sunday October 10 2004, @12:01PM (#10486530) Homepage
    If that actually were Murphy's Law [wikipedia.org], then that would be an impressive story.

    It's not, it's not the same thing as Sod's Law, and the law you're thinking of is Finagle's.

    Ironicly, having it called Murphy's Law by a reporter from the Courier-Mail is an example of Murphy's Law.

  • by starling (26204) <strayling20@gmail.com> on Sunday October 10 2004, @12:06PM (#10486557)
    Murphy's Law: If it can go wrong it will

    Sod's Law: It will go wrong at the worst posible time.
  • by freshmkr (132808) on Sunday October 10 2004, @12:52PM (#10486830) Homepage
    Don't you like it when maths back up common sense ?

    The equation in the post is a model---an invention for the purposes of prediction and description. It's effectively a mathematical restatement of common sense insights and (hopefully) statistical tendencies derived from psychological and economic studies. So to say that this work backs up common sense is missing the point to some extent: most of the meat was there first as common sense, and the math just expresses it more precisely and more in keeping with observed data.

    Note that F=ma and the rest of Newton's laws also form a model in the same way that this equation does. What made them so revolutionary was that the ideas behind the models were very powerful, making the models themselves extremely accurate. We'll have to wait and see whether this Murphy's Law model is backed by similarly potent insights.

    --Tom
  • by StateOfTheUnion (762194) on Sunday October 10 2004, @01:42PM (#10487101) Homepage
    It amazes me that many here think that the formula is merely a joke . . . perhaps this is a humorous formula, but similar formulas are used in the manufacturing industry to prioritize problems and issues in manufacturing. Problems are related to one another by ranking their relative severity, detectability and frequency . . . sometime also cost factors or normal maintenance factors are included.

    These factors are often multiplied together to result in a number that is used to prioritize the limited funds available to process improvement or maintenance.

    These ideas are not new . . . they were developed by Japanese manufacturers and the US auto industry decades ago . . They are called Failure Modes and Effects Analyses. They are often used in conjunction with statisical process control efforts to reduce variability and downtime.

  • by Anonymous Coward on Sunday October 10 2004, @02:34PM (#10487393)
    Man will I get my coffee in this morning?

    ((U+C+I) x (10-S))/20 x A x 1/(1-sin(F/10))

    Urgency = yeah I'd give that a 50, I mean it's pretty urgent.

    Complexity = it's pretty simple so a 1.

    Importance = it's not important for my boss, but really important for me, so a 400.

    Skill = well a child or drunk person might have problems, so it sounds like a 4.

    Frequency = well, I'll probably want 2 cups today.

    Aggravation = yeah I'll get really aggrivated without my coffee, so 100 is about right.

    Let's see plug all those in:
    ((50 + 1 + 400) x (10 - 4)) / 20 x 100 X 1/(1 - sin(2/10))
    bust out calc.exe and punch in the numbers right:

    1.3482771486352022902422017615702

    Alright now I'm rocking. There is 1.3482771486352022902422017615702 that I'll get my 2 cups of coffee today. Glad that's straightened out.

    PS. I think magic 8 ball is faster.
  • by sqwrell (820572) on Sunday October 10 2004, @02:52PM (#10487489)
    INTERESTING ADDENDUM FROM RBL (first featured in RBL's KISS Guide to
    Windows, 1999): http://rblevin.net

    It's ironic. One of the world's favorite axioms on the inevitability of
    failure is itself an example of such inevitability. It's Murphy's Law, most
    often stated as "anything that can go wrong, will." The irony: That's not
    Murphy's Law at all. It's "Finagle's Law of Dynamic Negatives," devised by
    the famous science fiction author Larry Niven. The real Murphy's Law was
    coined sometime around 1949 by USAF engineer Edward A. Murphy Jr.

    Murphy was part of a team of USAF engineers working on a project that tested
    the effects of extreme G-forces on the human body. One such test involved
    mounting 16 sensors to 16 different parts of the test subject's body. Each
    sensor could be connected in one of two ways: Correctly or incorrectly. On
    the first run, a technician installed all 16 sensors backwards, after which
    Murphy issued his now-famous maxim: "If there are two or more ways to do
    something, and one of those ways can result in a catastrophe, then someone
    will do it." Someone did, and now Finagle's Law is almost always misrepresented as Murphy's.
  • by knitterb (103829) on Sunday October 10 2004, @03:01PM (#10487539) Homepage
    I have a short fuse, so:

    ((U+C+I) x (10-S))/20 x A x 1/(1-sin(F/10))

    should be rewritten as:

    ((U+C+I) x (10-S))/20 x A^2 x 1/(1-sin(F/10))

    !!
  • by da3dAlus (20553) on Sunday October 10 2004, @03:22PM (#10487641) Homepage Journal
    For those that didn't RTFM, the value for each variable should be on a scale of 1-9, with 9 being very high. A (aggrivation) should be 0.7 as set after the study. I put together something in PHP [dyndns.org] just to do the work for me. The biggest variable seems to be skill--with all others set to very high (9) it certainly "proves" that an idiot can totally screw stuff up.
    • Re:Bullcrap (Score:3, Funny)

      by Anonymous Coward

      this is psuedo science at best. A scientific law should be provable by repetation. You can't know somehting will go wrong every time.
      Ahh, but what if the "something" was your spelling, and "going wrong every time" referred to at least one error per sentence? Could we prove it then?
    • Re:Bullcrap (Score:3, Funny)

      by pi_rules (123171) *
      You can't know something will go wrong every time.


      You sure about that?

      You want my job?

      Follow me around for a day. You'll change your tune.
    • Re:Bullcrap (Score:3, Informative)

      Actually, most people have the wrong impression of what Murphy's Law actually is. It doesn't state that things go wrong at the worst moments, it states that if there exists the possibility that something can go wrong, then it eventually will. Murphy developed it when he was working on the reliability of systems as a function of their components:

      [lim(L -> infinity)][P(L < infinity|some component has a positive failure rate)] = 1 where L is the lifetime of the system