This is the Planning Fallacy, for which the remedy is the Outside View: ask how similar projects have turned out in the past. That will likely be more accurate than imagining how this particular project will go.
I have heard (but do not have personal experience) of a rule of thumb for software developers when quoting a number of days work for a project. Imagine the longest it could possibly take, then multiply by three.
But perhaps you have not taken an outside view at the start, and got into a project that is multiplying like a hydra? Then take the outside view now, avoid the Sunk Cost fallacy, and ask, is the difference in payoff from completing vs. abandoning the project worth the difference in costs, now realistically estimated, that will be incurred from here on?
You do your realistic estimate, and six months later are in the same boat. What now?
If it helps you consider the problem, imagine that all the additional work is coming from another party whom you’re contracted to work for, and who is adjusting the workload—without violating the contract—as you’re completing it.
Granted. And don’t agree to non-iterative Prisoner’s Dilemmas, either.
You’re not always in a situation where this matters. Your boss agreed to the contract. Your boss is a perfect rationalist, who completely ignores sunk costs, and has produced perfect probability distributions, which include the knowledge that the other party is adjusting the workload. You suspect the other party at this point has a spy in your organization adjusting their requests according to his team of analysts’ probability distributions to maximize the value they can extract from your company. How do you convince your boss it’s not worth it to continue the project, regardless of the probability distribution he’s currently produced?
At this point you’re just responding to every answer to “what would you do?” by inventing another scenario designed to make it fail, and asking the same question again. But these scenarios, like the excuses of the man who claims to have a dragon in his garage, are raised to your attention not by reality, but by the task of finding a way around the answers you have received. There is no end to this process, because for every plan, the outcome pump in your head can imagine a way it could fail.
The point was to explicate an issue with a fallacy.
I do find the anger about it mildly amusing, because it is coming entirely from people whose reaction to a hypothetical was to immediately dissect and reject it, then get annoyed when I continued to insist that the hypothetical held as-is.
That was the extent of my “trolling”, to insist that the hypothetical held as-is, and to mark it as a loss when they continued to reject it—the extent of their losing was merely the degree to which they continued to insist that the real issue was that the subject in the hypothetical was doing what the hypothetical explicitly said they were not doing—making inaccurate predictions.
You do so. They adjust the amount they ask for as you proceed. Again, if it helps, you can assume they have a spy in your organization, and are calibrating against your adjustments.
You need to change your estimate to a value that will be accurate after they adjust the amount. For instance, if you would normally estimate 10 days, but you know that estimating X would lead to them increasing the workload by 1⁄3 X, you should estimate 15 days, since 15 days would lead them to increase the workload by 5 days, making the result actually be 15. This is the estimation equivalent of gross-up.
I’m not reversing the math. They increase the workload by 1⁄3of your prediction, so you give them a prediction which is sized such that, after adding the current workload to the increase based on your prediction, you get the prediction.
And you don’t need to predict the next round of mugging because the idea is to give a prediction which takes into account all successive rounds of mugging. If the sum of all these rounds is greater than 100%, the problem can never end at all. If it’s less, you can do what I said.
I’m not reversing the math. They increase the workload by 1⁄3 of your prediction, so you give them a prediction which is sized such that, after adding the current workload to the increase based on your prediction, you get the prediction.
It’d be 1⁄2 your prediction, if you’re giving them 10 days and want to arrive at 15 after they add their increase. Doesn’t actually matter, though, you made your point clear.
And you don’t need to predict the next round of mugging because the idea is to give a prediction which takes into account all successive rounds of mugging. If the sum of all these rounds is greater than 100%, the problem can never end at all. If it’s less, you can do what I said.
They’re adjusting their mugging so that it’s always more profitable for you to continue than stop, if you discount what you’ve already spent. They’ve anticipated your predictions, and have priced accordingly.
That’s assuming they want to maximize their mugging. They could execute only one or two muggings, and you might not catch on at all.
It’d be 1⁄2 your prediction, if you’re giving them 10 days and want to arrive at 15 after they add their increase.
It’s 1⁄2 of your non-mugging prediction, but it’s 1⁄3 of your stated (with-mugging) prediction. You’re trying to arrange it so that non-mugging prediction + mugging based on with-mugging prediction = with-mugging prediction.
This is the Planning Fallacy, for which the remedy is the Outside View: ask how similar projects have turned out in the past. That will likely be more accurate than imagining how this particular project will go.
I have heard (but do not have personal experience) of a rule of thumb for software developers when quoting a number of days work for a project. Imagine the longest it could possibly take, then multiply by three.
But perhaps you have not taken an outside view at the start, and got into a project that is multiplying like a hydra? Then take the outside view now, avoid the Sunk Cost fallacy, and ask, is the difference in payoff from completing vs. abandoning the project worth the difference in costs, now realistically estimated, that will be incurred from here on?
You do your realistic estimate, and six months later are in the same boat. What now?
If it helps you consider the problem, imagine that all the additional work is coming from another party whom you’re contracted to work for, and who is adjusting the workload—without violating the contract—as you’re completing it.
Bad contract. Don’t agree that sort of contract next time.
Granted. And don’t agree to non-iterative Prisoner’s Dilemmas, either.
You’re not always in a situation where this matters. Your boss agreed to the contract. Your boss is a perfect rationalist, who completely ignores sunk costs, and has produced perfect probability distributions, which include the knowledge that the other party is adjusting the workload. You suspect the other party at this point has a spy in your organization adjusting their requests according to his team of analysts’ probability distributions to maximize the value they can extract from your company. How do you convince your boss it’s not worth it to continue the project, regardless of the probability distribution he’s currently produced?
At this point you’re just responding to every answer to “what would you do?” by inventing another scenario designed to make it fail, and asking the same question again. But these scenarios, like the excuses of the man who claims to have a dragon in his garage, are raised to your attention not by reality, but by the task of finding a way around the answers you have received. There is no end to this process, because for every plan, the outcome pump in your head can imagine a way it could fail.
It is futile to engage in this any further.
That’s the point.
That point being, it appears, “HEY GUYS I TRIED TO PISS YOU OFF AND YOU GOT PISSED OFF I WINZ0RZ HAHAHA L00K @ ALL MY DOWNVOTZ!1!!”.
The point was to explicate an issue with a fallacy.
I do find the anger about it mildly amusing, because it is coming entirely from people whose reaction to a hypothetical was to immediately dissect and reject it, then get annoyed when I continued to insist that the hypothetical held as-is.
That was the extent of my “trolling”, to insist that the hypothetical held as-is, and to mark it as a loss when they continued to reject it—the extent of their losing was merely the degree to which they continued to insist that the real issue was that the subject in the hypothetical was doing what the hypothetical explicitly said they were not doing—making inaccurate predictions.
Your estimate of the time it takes needs to take into account the probability that the third party will increase the workload.
You do so. They adjust the amount they ask for as you proceed. Again, if it helps, you can assume they have a spy in your organization, and are calibrating against your adjustments.
You need to change your estimate to a value that will be accurate after they adjust the amount. For instance, if you would normally estimate 10 days, but you know that estimating X would lead to them increasing the workload by 1⁄3 X, you should estimate 15 days, since 15 days would lead them to increase the workload by 5 days, making the result actually be 15. This is the estimation equivalent of gross-up.
I think you’re reversing the math, but I get your gist.
And accurately predicting this round of mugging doesn’t help you deal with the next round of mugging.
I’m not reversing the math. They increase the workload by 1⁄3 of your prediction, so you give them a prediction which is sized such that, after adding the current workload to the increase based on your prediction, you get the prediction.
And you don’t need to predict the next round of mugging because the idea is to give a prediction which takes into account all successive rounds of mugging. If the sum of all these rounds is greater than 100%, the problem can never end at all. If it’s less, you can do what I said.
It’d be 1⁄2 your prediction, if you’re giving them 10 days and want to arrive at 15 after they add their increase. Doesn’t actually matter, though, you made your point clear.
They’re adjusting their mugging so that it’s always more profitable for you to continue than stop, if you discount what you’ve already spent. They’ve anticipated your predictions, and have priced accordingly.
That’s assuming they want to maximize their mugging. They could execute only one or two muggings, and you might not catch on at all.
It’s 1⁄2 of your non-mugging prediction, but it’s 1⁄3 of your stated (with-mugging) prediction. You’re trying to arrange it so that non-mugging prediction + mugging based on with-mugging prediction = with-mugging prediction.