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Science

How Well Do You Estimate? 374

Posted by michael
from the SWAG dept.
A random UK blogger has published a quiz asking readers to estimate various numeric values which they may or may not have knowledge of; and has analyzed the resulting answers to determine how well people guess. The first part of the results looks at some specific questions, and the second part takes a look at the quiz overall.
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How Well Do You Estimate?

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  • by garcia (6573) * on Friday September 10, 2004 @11:07AM (#10212781) Homepage
    I estimate that I would end up somewhere in the middle.
    • by BoldAC (735721) on Friday September 10, 2004 @11:11AM (#10212839)
      Reminds me of the joke...

      Why can't girls measure distances?

      (Holding up a pinkie)

      Because they've been told that THIS is 6 inches all their life.

      AC
    • by m_chan (95943) on Friday September 10, 2004 @11:31AM (#10213069) Homepage
      I estimate that I would end up somewhere in the middle.

      Does that imply that you are mean spirited?
    • by hackstraw (262471) * on Friday September 10, 2004 @11:44AM (#10213213)
      I estimate that I would end up somewhere in the middle.

      You must not be an American then :)

      Take for example graduating from college. Did you know that there are no "below average" college graduates? Proof: In order to graduate from college you must have a GPA equating to a C or better. A C is average, therefore there are no below average college graduates.

      Other estimates that I ask people from time to time. What percentage of the US population is African American (black)? What percentage of the US population has a college degree?

      Although the African American question is a little skewed because of the area I live in does in fact have about 30-40% of the population as being black, the national average in 2002 is 13%. I typically get answers that the national average is 30-40%.

      The college degree question is also very off. I typically get answers around 50% or higher, where its 27% as of 2003. Its some kind of myth here in the US that everyone has to go to college so they can do unskilled labor the rest of their lives. In fact, my aunt was lecturing her (adult) son that got his girlfriend pregnant with the "How are you going to pay for the kid to go to college?" routine. When neither of her parents went to college, neither her nor her husband went to college, and none of her 2 children went to college.

      Ask an American and a Japanese if they are "good in math". The Japanese will typically say "no", the American will say "yes". Ask the same 2 kids to take a standardized math test, the Japanese will score better than the American.

      However, although its important to feel good, its more important to look good!
      • by garcia (6573) *
        Take for example graduating from college. Did you know that there are no "below average" college graduates? Proof: In order to graduate from college you must have a GPA equating to a C or better. A C is average, therefore there are no below average college graduates.

        The average college graduate would be a 3.0 student?
        • by ack154 (591432) * on Friday September 10, 2004 @11:59AM (#10213369)
          I'm not sure what school you went to, but 3.0 was a B at Penn State.

          A: 4.0
          A-: 3.67
          B+: 3.33
          B: 3.0
          B-: 2.67
          C+: 2.33
          C: 2.0
          etc.
      • by Anonymous Coward

        Take for example graduating from college. Did you know that there are no "below average" college graduates? Proof: In order to graduate from college you must have a GPA equating to a C or better. A C is average, therefore there are no below average college graduates.

        That's not true. Lets say set A is the set of all people going to college. The people who are above the average of set A get to be part of set B, which is the subset of A that graduates. Everyone in set B is above average compared to set A,

      • by Godeke (32895) * on Friday September 10, 2004 @11:58AM (#10213357)
        You must not have gone to college then. :)

        Yes, you need at least specific average to *graduate*, but then you don't have any assurance of doing so. My wife teaches at a college and I can assure you that there are many D's and F's given out. However, unlike highschool and social promotion thereof, those people either shape up (and retake the class) or ship out (dropping out). Many do the latter (thus "x years college" being an popular answer to last grade completed).

        Graduate school is a bit different, since you need a B (3.0) average to remain in it. C's are suspension and lower is removal from the program.

        I think the grades represent how some hypothetical "average" community would fair. If you are in college, you *should* fair better than the community, and if you are in graduate school you *should* fair far better than the community. Those who don't shouldn't be at that level.
        • by hackstraw (262471) *
          You must not have gone to college then. :)

          Actually, I did and have either been in college or employed by one for 15 of the past 17 years, and that silly argument was a rip off of a position by a professor of mine when I was a senior in college. He was trying to emphasize how grades have been inflated over they years in American universities. He stated that by the university's definition that "C" was "average". Also, by the university's rules one must have a "C" or better to graduate (this was a fairly
      • Perspective (Score:3, Interesting)

        by msobkow (48369)

        You would be describing the difference between localized perception and overall truth, the essential gap between concept and reality.

        For example, I can look at the North American business market and go "Wow! Microsoft owns this market!" because all I see is Windows on the desktops.

        But in truth, it is the back-end data servers from a myriad of companies and providers which are entrusted with the critical business information, not the desktop. The desktop is merely an access point and a collection of ut

      • by servognome (738846) on Friday September 10, 2004 @12:48PM (#10213830)
        Did you know that there are no "below average" college graduates? Proof: In order to graduate from college you must have a GPA equating to a C or better.
        That is because grades should be a reflection of a student's mastery of the material, not how a student relates to their peers. There are classes where 70% is an A, not to get more students with A's but because that is the expected level of understanding. In fact, that class had less A's than most others with the typical 90% scale.
        Ask an American and a Japanese if they are "good in math". The Japanese will typically say "no", the American will say "yes".
        Most Americans feel they are not good at math and ungood at egnlish.
      • by danila (69889) on Friday September 10, 2004 @01:35PM (#10214285) Homepage
        Its some kind of myth here in the US that everyone has to go to college so they can do unskilled labor the rest of their lives.

        This is not specific to the US. In Russia most people overestimate the percentage of people with higher education as well. (Don't have the reference handy, but you probably can't read in Russian anyway - but it's on fom.ru). Also, about 60% of Russians said they want their kids to become scientists - even while the average salary in science is around povery line and everyone knows it.

        There are a lot of stereotypes regarding science, scientists and education, but we must be thankful, because they are mostly positive. :) For example, did you know that 52% of Europeans agree that "science and technology will solve any problem that we will face in the future" (Eurobarometer 2003 study). Similar results are observed in Japan and the US.

        People are optimists and it shows. In fact, it is known in sociology that in many surveys (especially those about the future) people first make up their mind on whether they are optimistic or pessimistic and then answer based on this, regardless of the particular question. :)
        • by Anixamander (448308) on Friday September 10, 2004 @02:22PM (#10214817) Journal
          In Russia most people overestimate the percentage of people with higher education as well. (Don't have the reference handy, but you probably can't read in Russian anyway - but it's on fom.ru). Also, about 60% of Russians said they want their kids to become scientists - even while the average salary in science is around povery line and everyone knows it.


          No offense, but this is the worst In Soviet Russia joke ever.
  • good point (Score:5, Funny)

    by PatrickThomson (712694) on Friday September 10, 2004 @11:08AM (#10212800)
    How Well Do You Estimate?

    With 44.7% accuracy!

    more or less.

    • I thought the story was going to be about how well we estimate distances and the such...

      If that was the case, I'd say I over-estimate for the most part.

      10, 12 inches... that's it!

  • Mirrors (Score:5, Funny)

    by wetlettuce (765604) on Friday September 10, 2004 @11:09AM (#10212803) Homepage
    I would estimate that that server stayed up less than 2 minutes after the story was published. Mirrors anyone?
    • Not too sure if you already read it or not, but here's a quick passage:

      The real ulterior motive of the quiz was to test the theory that people who are incompetent in a given field are also lousy at estimating their own competence. I wanted to see whether the respondents who gave the poorest answers to the estimation questions were also likely to give unreasonably narrow uncertainties.

      It turns out that they don't. The uncertainties given tended to be more-or-less reasonable estimates of uncertainties.

      • Re:Mirrors (Score:3, Informative)

        by bunratty (545641)
        There are two estimates involved. One is the estimate of the true value of something. The other estimate is the competence of the person giving the estimate. It is the second type of estimate that correllates well with the actual competence of the person giving the estimate.

        In other words, people really do know what they don't know, and approximately how well they don't know it. Of course, I didn't actually read the article, but I believe this to be a reasonably good summary of it.

    • Re:Mirrors (Score:2, Insightful)

      by crazy blade (519548)

      Perhaps /. scripts should be modified to automatically prepend a Coral [nyu.edu] link to user provided links.

      This way, assuming someone posts a story with:

      at link
      X you will find freebeer!

      It would come up as:

      at link
      X (non-Coral link) you will find freebeer!
  • 5 comments before the server collapses under the slashdotting. Pretty close?
    • Since the Slashdot effect is so powerful, why doesn't Slashdot offer a section for posting full copies of spam mail, with headers.

      The true source IP can be extracted and listed as a special bulletin complete with a link to said IP address. When all the slashdot readers try to connect to the trojaned server, it clogs up the pipeline for the ISP and MAYBE they will get a clue that something is wrong. Meanwhile, that's one less system spewing out mail for a while.

      Or better yet, subtitute the IP address in a
  • by dario_moreno (263767) * on Friday September 10, 2004 @11:09AM (#10212812) Homepage Journal

    about 1 minute and 10 requests...

    who the hell is Tony Benn by the way ?
  • by swordboy (472941) on Friday September 10, 2004 @11:09AM (#10212814) Journal
  • I estimate (Score:3, Funny)

    by penguinoid (724646) <spambait001@yahoo.com> on Friday September 10, 2004 @11:09AM (#10212815) Homepage Journal
    that I will get a +3, funny
    • by blibloblu (810226)
      Damn! Parent got +5, please mod him down quick!
    • by mark0 (750639)
      It was all I could do to not use my mod points to adjust you down so you'd be right...
    • Re:I estimate (Score:5, Interesting)

      by meringuoid (568297) on Friday September 10, 2004 @11:29AM (#10213044)
      I estimate that anything that gets modded up to +3 within the first hour of an article will inevitably become a +5. Anything modded down to +1 will inevitably become a -1.

      Substitute +2 and 0 for low karma posters, obviously...

      Looking back on my posts, I have shedloads of +5s and occasional -1s in a long list of +2s... but very few +3s. Moderation is a runaway process, in which the difference between +5 and -1 is a single modpoint.

      • Re:I estimate (Score:4, Insightful)

        by JWW (79176) on Friday September 10, 2004 @12:23PM (#10213583)
        I think you had it in your first statement. The chances of getting a +5 greatly decrease with relation to the age of the discussion.

        +3 and +4s can be had, but they generally tend to be later posts to a discussion.

        Moderation is not a runaway process than it is a positive feedback loop in relation to time and mod points.
      • by irhtfp (581712) on Friday September 10, 2004 @02:13PM (#10214711)
        Or "How to get quick karma when you're a newbie."

        If you're need quick karma, do the following:

        1. Post only to new discussions - those with less than 30 comments.

        2. Do not reply to main story - instead reply to the first highly modded post.

        3. Quote lots of facts or say something political (but keep it loosely on topic and don't use inflammatory statements or you'll get modded a troll).

        4. Make your posts long. Long posts are always "Interesting". It's axiomatic.

        This will probably get modded Offtopic but since I've got karma to burn and I know how to get it back - I don't think I really care.

  • Uh-oh (Score:5, Funny)

    by lukewarmfusion (726141) on Friday September 10, 2004 @11:09AM (#10212816) Homepage Journal
    Server timed out trying to contact ex-parrot.com.

    Looks like we've got an ex-webserver on our hands.
    .
    .
    "It's not dead, it's IIS!"
    • Re:Uh-oh (Score:5, Funny)

      by bittmann (118697) on Friday September 10, 2004 @11:19AM (#10212938) Journal
      It's not pining, it's passed on. This webserver is no more. It has ceased to be. It's expired and gone to meet its maker. This is a late webserver. It's a stiff. Bereft of life, it rests in peace. If you hadn't nailed it to an IP address, it would be pushing up the daisies. It's rung down the curtain and joined the choir invisible. This is an ex-webserver.
  • Mythical Man Month (Score:3, Interesting)

    by rjstanford (69735) on Friday September 10, 2004 @11:09AM (#10212817) Homepage Journal
    Does nobody here on Slashdot even remember the Mythical Man Month any more? The section on estimation and back of the envelope calculations (which I wouldn't be surprised if this blog pulled from, but I can't tell because its slashdotted already) was quite enlightening. Its main point was that people were way too confident in their estimates, even when they would admit that they had no idea.
    • by Alomex (148003) on Friday September 10, 2004 @11:21AM (#10212961) Homepage
      Does nobody here on Slashdot even remember the Mythical Man Month any more? The section on estimation and back of the envelope calculations was quite enlightening.

      Clearly you don't. That section is in Programming Pearls by Bentley, not the Mythical Man Month.

    • by dpilot (134227) on Friday September 10, 2004 @11:26AM (#10213017) Homepage Journal
      I've never actually read MMM, but...

      What really torques me is when you make an estimate early in the program,
      and you know it's only an estimate,
      and since you have only limited information it's not even a very good estimate,
      and you give management all of those caveats up front,
      it just doesn't matter.

      For the rest of the life of the program, better estimates using more information, and even the reality of program execution will all be force-fit back into that original SWAG.

      But sometimes even that original SWAG didn't matter, because it might well have been force-fit into some manager's wish-list.
      • Give them a range instead of a number.
        "The project will be done in 1 to 1000 weeks"

        If they demand a single number, insist they use the worst one.

        If they ask for a better estimate (i.e. smaller range) tell them you can have one in 1 to 10 days.

        -- less is better.
      • What? Your management actually pays attention to your estimates? Where I used to work, I was always told whatever I was working on would take two weeks, no matter whether I said it would take two days or two months!
    • Its main point was that people were way too confident in their estimates, even when they would admit that they had no idea.

      You've just described Management. O_O

      Soko.
  • I'll estimate that in about an hour there will be 347 replies posted, about 10 of which will be +5 insightful and, oh, maybe 13 +5 funny.
  • by Anonymous Coward on Friday September 10, 2004 @11:14AM (#10212864)
    that we'll end up with about 30 comments about how fast the site went down due to slashdotting....
  • I'd estimate that I made it to, oh, say question 24 before the story went live and site died as fast as you can say "Please estimate the air speed of an unladen swallow"

    --
    I write stuff [livejournal.com], but not that well and not that often...

  • by Anonymous Coward on Friday September 10, 2004 @11:14AM (#10212866)
    I can usually estimate within plus or minus one or two Libraries of Congress every time.
  • I actually just finished this book. It's an oldy but goody, and it should be required reading for the statistically challenged. (I.e, those subject to the whims of marketing droids)
  • by bittmann (118697) on Friday September 10, 2004 @11:15AM (#10212887) Journal
    Most folks are 70% correct, at least 30% of the time.
  • ISP bill this month, but of course, this is only an estimation.
  • Estimate (Score:5, Insightful)

    by pklong (323451) on Friday September 10, 2004 @11:18AM (#10212914) Homepage Journal
    I estimate that at about this point all the jokes about estimating will get tedious
  • by SavedLinuXgeeK (769306) on Friday September 10, 2004 @11:19AM (#10212933) Homepage
    I'm currently taking a course at my school, for essentially doing computations, but only up to a certain accuracy (estimation with precision). We basically build algorithms, that are normally simple enough to follow, and then just repeat the process until the desired precision is reached. There are multiple ways to do estimation. Like for square roots, you can actually used Fixed Point Iteration(x = g(x)), where g(x) = (x+x/n)/2, where n is the integer of the square root. Just continue that process for about 5 times, and the results are amazing.
    • I think you mean g(x) = (x+n/x)/2. Here's a scheme program to demonstrate it with c as the iteration count. You *nix users probably have guile to test it out. If I knew bc, I'd write it up in that instead.

      (define (sqr n c)
      (define (s x n c)
      (if (zero? c)
      x
      (s (/ (+ x (/ n x)) 2) n (- c 1))))
      (s n n c))
  • by Anonymous Coward on Friday September 10, 2004 @11:19AM (#10212935)
    Reminds me of a bit of training from my army days.

    If you have difficulty estimating a distance ( range), divide the distance in two, and try estimating that.

    This sounds stupid, but actually works. Well, it worked for me. I'll never forget how I laughed in my head at the suggestion, and my astonishment at it actually working.

    Mike.
  • Google Cache (Score:5, Informative)

    by Anonymous Coward on Friday September 10, 2004 @11:20AM (#10212946)
    Part 1 [66.102.9.104]
    Part 2 [66.102.9.104]
  • Estimating Anecdote (Score:5, Interesting)

    by freality (324306) on Friday September 10, 2004 @11:26AM (#10213016) Homepage Journal
    I used to work at a small datamining shop. The people there were very bright, some of them quite famous in the fields of statistics, number theory, etc.. One day, we were sitting in the front room of our offices having lunch, chewing the fat, as it were.

    At lunches, we would sometimes try to stump our CTO a grey beard who is famous for work in information theory and general genius. We had never succeeded, even with obscure questions in biology "How do Prions work?", physics "What order are the colors of the rainbow, and why?", "How does the Corriolus effect work?", etc. that none of us had any particular knowledge of, and always had to research afterwards to determine the correctness of his answers.

    So, I posed the question to the group "How many leaves are on that tree outside the window?" It was a ~30 foot tall, bushy tree in the height of summer. I hoped he'd take the bait.. I thought this was going to be very hard to "get right", and it would even be difficult come up with a plausible answer.

    After a few moments, I set off the responses by saying that I thought it easily had 10k leaves, possibly 20k or more.

    Everyone gasped. "Oh no! No way..." and then proceeded to offer lower and lower estimates.

    The responses started with me and made their way up in the seniority ranks (I was the most junior) all the way up to the CTO. He said "Oh! those kinds of things are notoriously hard to estimate. We typically overestimate grossly in counting things of plentitude. Oh, I don't know. 200?".

    Finally we had him. There was no way there were 200 leaves on that tree.

    Later, in discussion, a trend became clear. The more senior the person, the more conservative was their response, even to the ridiculous level of our CTO saying a tree in full flush, that he could see right outside of the window, had 200 leaves, when it most plainly had many, many more.

    Anyone want to hazard a guess? How many leaves on say, an adult Sycamore (or Maple, Oak, etc.)?
    • by savagedome (742194) on Friday September 10, 2004 @11:34AM (#10213107)
      ... After a 2 year study, the National Science Foundation announced the following results on America's recreational preferences:

      1. The sport of choice for unemployed or incarcerated people is: basketball.
      2. The sport of choice for maintenance level employees is: bowling.
      3. The sport of choice for blue-collar workers is: football.
      4. The sport of choice for supervisors is: baseball.
      5. The sport of choice for middle management is: tennis.
      6. The sport of choice for corporate officers is: golf.

      Conclusion: The higher you rise in the corporate structure, the smaller your balls become.
    • How many leaves on say, an adult Sycamore (or Maple, Oak, etc.)?

      There are about 10k-20k on the tree outside my window. It's about 8 stories high, not shadowed by other trees and I have no idea what kind of tree it is. I'm assuming there are few leaves near the core.

      So you have some sort of good estimates?
      • No I don't. I can't find anything on google either. There are many people who say it's a good exercise in estimation, but I can't find anyone who has actually validated their estimates.

        The situation was the same that day. We couldn't resolve it. Everyone agreed the CTO was way off, but we argued about whether 5k, 10k or 50k was more likely correct (in datamining, "likely correct" is all you talk about).

        We thought about doing some image processing. You could take a picture and do some counting using a
    • A large Oak may have 250,000, and I have to rake up every !^$!$#@&%^$ one of them!
    • Since we usually like to tell stories that show ourselves in a good light rather than bad, I'm guessing 10k. ;-)
    • by Scarblac (122480)
      I cheated and Googled. This horrific Google cache of a PowerPoint file [216.239.59.104] gives numbers of 100,000 for an oak, and 325,000 for an elm tree, "estimated using average branch-to-branchlet technique".

      The text is white on white, so it's probably really secret.

  • To clear up:

    Estimate: To calculate approximately (the amount, extent, magnitude, position, or value of something).

    Guess: To predict (a result or an event) without sufficient information.

    Predict: To state, tell about, or make known in advance, especially on the basis of special knowledge.

    Based on these definitions, different people would either guess or estimate (or state / predict) (the known value of) the distance between Edinburgh and Cardiff.

    I saw his nice graph, looks like SPSS.
  • Estimation is for slackers. I always use a tollerance of +-0.0

  • Time and Miles (Score:4, Interesting)

    by sys49152 (100346) on Friday September 10, 2004 @11:28AM (#10213035)
    The article's slashdotted, so I'm not sure what this is all about. But I've always prided myself on my ability to estimate time and miles. Frequently, I'll look at my watch and find it's, say, 3:00. Some time later I'll estimate that it's 4:22, look at my watch, and find it's 4:20.

    Similarly, I will look at the odometer in my car, drive a distance, and guess that it's 10 miles later. Looking down, 10.1.

    The best is when you combine them. "How long before we get there?" the wife asks. "About 47 minutes," say I, and 47 minutes later arrive at our destination.

    I note this only because most everyone else seems incredibly bad at this. As when someone gives you loose directions to a place like this, "Oh, go about 3 miles, then turn left on Main St." Half a mile later I'm slamming on the breaks 'cause I just past a sign saying "Main St." Or when they tell you it's a 5 minute drive, when it's really 15. Drives me batty.

    In short, I estimate that just about everyone sucks at estimating. Funny thing is people always over-estimate distance and under-estimate time.
    • That's easy when you're just 5 minutes away and then drive around the block for 42 minutes.
    • You'd rather be rich than supid? And you pride yourself on estimation? I'm estimating that that you're rich then, unless there is a break in my reasoning. Or maybe you got rich by designing a new form of brakes?

      I get so confused sometimes.
  • ... I'de have to say well to-QUITE-well.
  • by Mateito (746185) on Friday September 10, 2004 @11:30AM (#10213066) Homepage
    Yeah, I know everybody is after funny mods, but you don't "estimate" a future event, you predict it.

    Estimation is making an educated guess at a quantity without scientifically measuring it, usually with some sort of observation.

    "I reckon thats 8 inches long and 2 inches thick."

    Prediction is using past experience to state that an event will happen.
  • The server seems to be slow but eventually responsive, so I got a peek at the results and part of the test.

    When Poindexter tried to set up a terror gambling pool to predict terror events, he was relying on something like this-- that collective knowledge would somehow converge on the right answer, or something close enough to be useful.

    The results from this survey suggest that that's probably true for something where the guessers/bettors actually have some real knowledge, however deeply buried in their mem
  • About the article... (Score:5, Interesting)

    by Ignignot (782335) on Friday September 10, 2004 @11:36AM (#10213122) Journal
    As almost every single comment up until now talks about personal experiences or makes stupid jokes, I'm going to critique the method he uses to score an answer. From the second link (find a google cache of it to read it) you can see that he treats each answer and estimate of the accuracy of the answer as a single question - you get a single score from both. I think this approach is fundamentally flawed. Why not instead score the guess (with some sort of algorithm like the one he uses) and then score the guess of accuracy by the same method. Then if you want a single number, add the two together. Right now if you guess well and guess your accuracy perfectly, you get zero points. That is completely out of whack. Instead, using my way you score the best possible score when you guess perfectly and perfectly guess your accuracy, and the worst possible score when you guess horribly and horribly guess your accuracy. The scores move between those two extremes rationally too. As he wanted people who guessed zero error (thought their guess was a perfect guess) to get no points, he obviously had an agenda - that people should be penalized for thinking they are perfectly right. In no way is this an unbiased or useful test.
  • He's not so random, he was the man behind the Political Survey [beasts.org].
  • by MikeMacK (788889) on Friday September 10, 2004 @11:39AM (#10213156)
    * [How long does] light from the Sun [take] to reach the Earth?

    I guess it depends on if the chute opens or not [slashdot.org]

  • by notthepainter (759494) <oblique@@@alum...mit...edu> on Friday September 10, 2004 @11:42AM (#10213188) Homepage
    I have two kids in elementary school and I was shocked to see how they teach math these days. Pleasantly shocked.

    They spend a lot of time on grouping. For example What is 97 + 198? I was taught to add 8 and 7, carry the one etc...

    They are taught to group the numbers, the instantly recognize that the answer is close to 300, then see how it differs from the 100s. 97 is 3 less, 198 is 2 less. Now add the 3 and 2, getting 5.

    The answer is of course 300 - 5, or 295.

    I find this method very intuitive.

    • That's cool - I've pretty much always done that, much to the annoyance of my wife when I tried to explain it to her at some point, but I never realized that it was considered legitimate by anyone. Same works for multiplying as well:

      ( x * 78 )
      ( x * 80 ) - ( 2 x ) [ since 2x is easy ]
      ( x * 100 ) - ( 2 x * 10 ) - ( 2 x )

      Efficient? Probably not for a computer, but its fast for humans.
  • by MajorDick (735308) on Friday September 10, 2004 @11:43AM (#10213203)
    My father, a long time IT guy since '63 or so, told me when estimating a project development time take your original SNAP off the top of your head guess , double it , then double it again.

    While I wont say its perfect it comes darn close when you take into account all the administrative overhead, meeting, decisions, etc.

    And since MOST of us developers have a good idead of what our real capablities are. We want to blurt out an ego answer to ourselves, yeah 50 hrs, and if we were in a cage locked up with NOTHING else to do we probably could do it in that timeframe, but bathroom caffine breaks etc take their toll, errr troll
  • half of the time I'm almost always pretty close to the correct.
  • by MarkPNeyer (729607) on Friday September 10, 2004 @11:46AM (#10213237)

    People at large seem to lack important estimation skills. In my observation, people seem to consider a billion, million, and trillion more or less the same. In a December 2003 issue of Vanity Fair, Graydon Carter estimated the U.S. Budget deficit at 6.4 quadrillion dollars. To anyone with an actual understanding of such a number, that figure is completely ludicrous - but it went unoticed by the editors.

    We need increased numerical literacy - so that people understand just how much money 1 million vs. 10 million vs 100 million etc etc actually is. I'm sick of hearing someone say 'are you aware that we spend $x billion dollars a year on thing y?' and then expect me to be outraged or surprised. They just think that 'billion' sounds like a lot - but would they have the same response if it were $x*100 million, or $x*10 billion?

    • It is amazing that you write a rant about how people don't understand numbers and then your sig is 2 + 2 = 5 (For extremely large values of 2) . Joking aside, you're running into the "big number" problem. Once numbers get past a certain point, people can't conceptualize them. A trillion may be a million million, but to someone who makes $30k/year, it is just a lot. I just don't think we're wired to understand what that much money really represents.
  • How long is a piece of string?
  • significance (Score:5, Interesting)

    by digitalhermit (113459) on Friday September 10, 2004 @12:00PM (#10213381) Homepage
    On a side note, there are many errors made when newspapers, magazines, etc. estimate numbers. Sometimes they will round values before presenting the final number, causing a huge difference. Or they will give some value like $6,021.50 when some of the values have only two or three significant digits. Or they'll make some hideous stats error such as adding two means together and not weighting the scores appropriately. An excellent book that discusses this is John Allen Paulos' "A Mathematician Reads the Newspaper."

  • I propose a test: try to summarize the article. /just too lazy to read.
  • by Col. Klink (retired) (11632) on Friday September 10, 2004 @12:18PM (#10213530)
    A former co-worker was telling us about some of her tutoring experiences. She was helping some high school kids with the concept of estimation. She looked at the ceiling and said you could estimate that it was about 10 feet high. She told them that "the great thing about estimation is that it doesn't have to be the 'right' answer."

    So she pointed a car parked nearby and asked one of the students how far he thought the car was. His reply, "50 gallons."

    Incredulous, she said that his answer didn't make sense.

    "But that's the great thing about estimation! It doesn't have to be right!"
  • by MarkLR (236125) on Friday September 10, 2004 @12:57PM (#10213924)
    Some of the questions in the quiz are not suitable for estimation.

    For example answering "the year that Harold II became King of England" requires knowledge of English history. Any answer prior to the mid 1900s is a reasonable one for a person who only knows about Queen Elizabeth II.

    People with more knowledge know this a pre-Norman Conquest King and so the answer must be before 1066. But that reduction in the scope of the answer comes from existing knowledge not by estimating.
  • by peter303 (12292) on Friday September 10, 2004 @01:20PM (#10214152)
    This issue has been studied for many decades in order to help organizations minimize losses on bad bids. Courses [roseassoc.com] are taught on this. I took something like this once. There was an exercise to estimate the number of beans in jar. People's guesses fell along a curve called the binnormal distribution. From this equation you can estimate the best price to offer versus other people's bids in order to ocassionally win and make money at it.
  • by Titchener (769895) on Friday September 10, 2004 @01:40PM (#10214344)
    Reminds me of some work done by psychologists Kahneman and Tversky (Kahneman went on to win the nobel prize in economics for different studies). In their studies they had people do things like this (e.g., what year was the constitution adopted by the states). Supplying "anchors" influences your judgement. For example, supplying the anchor that the articles of confederation were ratified in 1781 (I think) would shift the answer toward 1781 compared with the case in which the anchor was that George Washington left office in 1796. The idea is that if you know a.) that the constitution came after the articles of confederation and b.) that the constitution was ratified before Washington left office, you will use specific dates associated with those events to anchor your answer.
  • by PMuse (320639) on Friday September 10, 2004 @02:09PM (#10214649)
    A fine quiz, but I hope he throws out his non-UK results by IP before he uses the data. For many of those topics, my poor American brain had no basis for an estimate and knew it.

    The data could be improved by adding the a "no-confidence" checkbox to each question in addition to demanding a numeric answer. With this, he could compare whether people's estimates were better or worse where they thought they knew the answer. This would make a nice complement to measuring raw estimating power.

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