7 ms·

I read this book called "How Big Things Get Done." I've seen my fair share of projects going haywire and I wanted to understand if we could do better. The book

• jakobloekke 2y ago
  Cannot recommend that book enough
• kqr 2y ago
  This goes beyond project estimations. The Metaculus tournaments have questions like > Will YouTube be banned in Russia before October 1? These are the kinds of questions most people I meet would claim are impossible to forecast accurately on because of their supposed uniqueness, yet the Metaculus community does it again and again. I believe the problem is a lack of statistical literacy. Back in the 1500s shipping insurance was priced under the assumption that if you just learned enough about the voyage you could tell for certain whether it would be successful or not. It took a revolution in mindset to ignore everything that makes a shipment unique and instead focus on what a primitive reference class of them have in common, and infer general success propensities from that. Most people I meet still don't understand this, and I think it will be a few more generations until statistical literacy is as widespread as the literal one.
  • tomlue 2y ago
    I know you're coming from a good place, but the 'most people I meet don't understand this' line about statistics is quite arrogant. Most people you meet are fully capable of understanding statistics; you should do a better job of explaining it when it comes up, or maybe you are the one who misunderstands. After all, most statisticians thought Marilyn vos Savant was wrong about the goats too...
    • robwwilliams 2y ago
      Not my experience at all. Just one example: try talking to physicians about false discovery rates; even those who do not profit from state-of-the art screening methods. Incorporating Bayesian methods is even a struggle for statisticians. It is a stuggle for me. John Ioannidis has much to say on this topic: https://en.wikipedia.org/wiki/John_Ioannidis https://en.wikipedia.org/wiki/John_Ioannidis
    • joebob42 2y ago
      My experience is that most people don't understand statistics and can be pretty easily mislead. That includes myself, with my only defense being that I'm at least aware statistics don't intuitively make sense and either ignore arguments based on them or if absolutely necessary invest the extra time to properly understand. Most people either don't realize this is necessary or don't have the background to do it even if they did, in my experience.
    • lordnacho 2y ago
      You don't have to be on the internet for long to see: - "Polls are useless, they only sampled a few thousand people" - "Why do we need the crime figures adjusted for the age/income/etc groups? Just gimme the raw truth!" Have to say, I think stats are the least well taught area in the math curriculum. Most people by far have no clue what Simpson's or Berkson's paradoxes are. Most people do not have the critical sense when presented with stats to ask questions like "how was the data collected" or "does it show what we think it shows". I just don't see it, tough ironically I don't have stats to back it up.
      • organsnyder 2y ago
        You don't have to be on the Internet long to see flat-earthers or any number of asinine ways of thinking. You can't stretch discrete observations from a supremely massive sample size into "most people".
        • ben_w 2y ago
          Gee, if only there was some kind of rigorous and well understood process for determining how to transform discrete observations according to how representative they are, such that we could build a model for a larger population. Something like that would be very useful for political decision, so perhaps we could name it after the latin word for "of the state"… ;P
  • dasil003 2y ago
    For forecasting with no agency involved this makes sense, but when you’re executing a project things get trickier. The hard part is finding appropriate reference classes to learn from while also not overlooking unique details that can sink your specific project.
  • card_zero 2y ago
    > the Metaculus community does it again and again. Do they? I can't see where on that site there is something like "history of predictions" or "track record". Edit: here. https://www.metaculus.com/questions/track-record/ https://www.metaculus.com/questions/track-record/ But now I can't tell if it's good or bad.
    • kqr 2y ago
      The binary calibration diagram is what I would focus on. Of all the times Metaculus has said there's an x % of something happening, it has happened nearly exactly x % of the time. That is both useful and a little remarkable!
      • Retric 2y ago
        That doesn’t necessarily imply individual predictions are particularly good. If between two outcomes I say X wins 50% and I pick the winner randomly I’m going to be correct 50% of the time. However, if I offered people bets at 50/50 odds based on those predictions I would lose a great deal of money to people making more accurate predictions.
        • kqr 2y ago
          This is true! The Metaculus community forecasts also performs very well (in terms of score) in tournaments including other aggregation mechanisms though.
      • LegionMammal978 2y ago
        It also seems gameable: for every big question of societal importance that people care about for its own sake, have a thousand random little questions where the outcome is dead obvious and can be predicted trivially. Would you know anything talking about weighing questions to account for this?
        • christianqchung 2y ago
          Trivial questions wouldn't result in a good histogram where a probability of 30% actually results in something happening roughly 1 in 3 times. Trivial would mean questions where the community forecast is 1% or 99%. Those are not the vast majority of questions on the site. It would be very boring if the site was 70% questions where the answer is obviously yes or obviously no. Additionally, many questions require that you give a distributional forecast, in effect giving you 25/50/75th percentile outcomes for questions such as "how much will Bitcoin be with at the end of 2024?" Who would be gaming the system here anyway, the site? Individual users?
  • krisoft 2y ago
    > Back in the 1500s shipping insurance was priced under the assumption that if you just learned enough about the voyage you could tell for certain whether it would be successful or not. Do you have a source on that? That sounds very unlikely to me. People just have to look at a single storm to see that it sometimes destroys some ships and does not destroy others. It is very clearly has a luck component. How could have anyone (at any time really) believe that "if you just learned enough about the voyage you could tell for certain whether it would be successful or not"?
    • kqr 2y ago
      Okay, that was an oversimplification. I have long wanted to write more on this but it never comes out right. What they did was determine the outcome with certainty barring the will of God or similar weasels. I.e. they did thorough investigations and then determined whether the shipment ought to be successful or not, and then the rest laid in the hands of deities or nature, in ways they assumed were incalculable. This normative perspective of what the future ought to be like is typical of statistical illiteracy. I'll get back to you on sources after dinner!
      • kqr 2y ago
        I think I got most of this from Willful Ignorance (Weisberg, 2014) but it was a while since I read it (and this was before I made more detailed notes) so I might be misremembering. There are what looks like fantastic books on the early days of probability and statistics aside from Weisberg (Ian Hacking is an author that comes to mind, and maybe Stephen Stigler?) but I have not yet taken the time to read them – I'll read more and write something up on this some day. But statistical understanding is such a recent phenomenon that we have been able to document its rise fairly well[1] which is fascinating in and of itself. [1]: And yet we don't know basic stuff like when the arithmetic mean became an acceptable way to aggregate data. Situations that obviously (to our eyes) call for an arithmetic mean in the 1630s were resolved some other way (often midrange, mode, or just a hand-picked observation that seemed somehow representative) and then suddenly in the 1680s we have this letter to a newspaper which uses the arithmetic mean as if it was the obvious thing to do and then its usage is relatively well documented after that. From what I understand we don't know what happened between 1630 and 1680 to cause this change in acceptance!
• pif 2y ago
  > 99.5% of those projects overrun their timeline or budget. This does not shock me. In the corporate world, plans are not there to be adhered to, but only to give upper management a feeling of having tightened the rope for those pesky engineers who wanted to work at a lazy pace. Such feeling usually vanishes as soon as reality kicks in.
  • zerodensity 2y ago
    I dunno, upper management normally move onto greener pastures long before reality comes crashing down. That does not happen until two managers over. But that's okay the new plan will fix everything.
    • bux93 2y ago
      This is why your project shouldn't be too small. If a project is projected to be finished in 6 months, the current manager will still be there, and the success or failure will reflect on their record. It can only go wrong and reflect badly on them. If a project will take 3 years, the manager can already collect their points for initiating a project with an incredible business case and innovative approach, leave after 18 months, and after a further six month, the new manager can say 'wow, my predecessor left a big mess, I'll clean it up/kill it'.
• steveBK123 2y ago
  I think a lot of modern US public works fall prey to politicians who think the objective of the project is the spending of the money. That is - they push for spending on transit so they can talk about how much, in dollars, they got passed in transit funding. The actual outcomes for many of them are, at best, inconsequential. Further cynicism could be layered in if you consider some of the blocks of donors (infrastructure contractors / RE devs / etc) and blocks of voters (union transit workers & construction workers) who are recipients again of the spending but not the outcomes. Finally a lot of the problems come from a long gap of not doing capital projects and so hollowing out of state capacity which has been outsourced. If you outsource your planning, they are less incentivized to re-use existing cookie-cutter plans for subway stations. If you outsource your project management, they are less incentivized to keep costs down. ETc.
  • pessimizer 2y ago
    > Further cynicism could be layered in if you consider some of the blocks of donors (infrastructure contractors / RE devs / etc) and blocks of voters (union transit workers & construction workers) who are recipients again of the spending but not the outcomes. It's probably best to think of an initial budget as a foothold, and that its ideal amount is low enough to be approved, but high enough to prevent the organization from changing direction after realizing that it's not going to be nearly enough i.e. to think in terms of "pot-commitment."
  • nitwit005 2y ago
    Personal suspicion is that real leadership is dull and thankless (like so many things in life). Announcing a big new transit project is exciting. Actually running the program well requires a lot of boring study, meetings, and management of details. Why bother, if the voters don't punish them for not doing it? You can find endless internet posts by people complaining their manager doesn't want to do the scheduling of employees, which is the most basic part of their job. It's too tedious, so they try to avoid it.
• bryananderson 2y ago
  This book is by Bent Flyvbjerg, the lead author of the paper being discussed here. He’s done a lot of great scholarship on how megaprojects go haywire, and uniqueness bias is definitely a big piece of it. You especially see this bias with North American public transit. Most of our transit is greatly deficient compared to much of the rest of the world, and vastly more expensive to build (even controlling for wages). But most NA transit leadership is almost aggressively incurious about learning from other countries, because we are very unique and special and exceptional, so their far better engineering and project management solutions just wouldn’t work here and aren’t even worth considering.
• bsder 2y ago
  > Others reasons for slipping include optimism bias, not relying on the right anchor, and strategic misrepresentation. Optimisim and misrepresentation are WAY more important. Most engineers I know of were a bit optimistic to other engineers. This leads to slippage because subtasks have a finite amount they can come in early but an almost infinite amount of time they can come in late. In addition, most engineers are acutely aware of what they think the project would take vs. what number management was willing to hear to launch the project. Combine both of these and your project will never come in even remotely close to the estimates.
  • atoav 2y ago
    And sometimes the reality is that the realistic answer to a time estimate is "If we are lucky it takes me 30 minutes, if we are unlucky 30 days". E.g. when it turns out to your surprise, that a part you had in your hardware design was replaced with a part that was 5 cents cheaper, but uses a undocumented protocol that someone has to re-implement, so a goal that was trivial in theory has suddenly involves hardcore reverse-engineering in a high pressure environment. A thing all engineers love. The only time someone can give you reasonably accurate estimates is when they do something that down to the tiniest detail they have done before. The problem with that is, that in software things change constantly. A thing that was trivial to do with library X and Component Y of version 0.9 might be a total pain in the rear with Library Z and Component Y of version 1.0. But yeah, unexperienced engineers are going to be optimistic that it is possible, because in theory it should be trivial.
    • dspillett 2y ago
      > And sometimes the reality is that the realistic answer to a time estimate is "If we are lucky it takes me 30 minutes, if we are unlucky 30 days". “I'll put that in Project as 60 minutes, then if you are luck you've got double time for contingency.” -- the external consultant acting as project manager. Been there before… Never give a best case estimate, or anything close to, even when quoting a range. Some will judge you, or worse make plans around you, based on that and little else, and it *ahem* isn't their fault if things overrun.
• carlmr 2y ago
  >In short, this bias leads planners to view their projects as unique, thereby disregarding valuable lessons from previous similar projects. I once had a discussion. We had some managers that would systematically over or underestimate their projects, mostly underestimate. I suggested that we take into account the estimation accuracy of previous projects for that manager and adjust their estimate. They said that each project is too unique to do this. But I saw the same optimism or pessimism playing out repeatedly for the same managers when looking at the numbers. Although tbf I think accurate estimation can be bad if the person managing the project knows about the estimation. Since if they have more time, there's less pressure, and they'll have overruns again, making the estimation inaccurate again. Hofstadter's law, to me, is less about accurate estimation and more about human psychology. If you know you have more time, you waste more time. This is also a failure-mode in agile project management. If you don't have strict deadlines, it's easy to fall into infinite iteration, because there's always something that could be done better.
• deleted 2y ago
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