> I hope that every infrastructure project tries to make a measure of the total economic gain of said project.
This is basically impossible to do short of shutting the system down for year to measure the loss (unthinkable).
And even then, you'd have a measurement that doesn't mean anything because it couldn't measure the opportunity costs of the path not taken when the chocie was made initially.
As a matter of fact, I'll go one step further: I don't even think the question makes sense.
Economies are chaotic systems, and even if it is sometimes rather clear after the fact that a specific choice leads to overall positive outcomes (such as choosing to implement a high-quality public transportation system in Switzerland), actually measuring the "gain" is basically impossible. Worse: it's an ill-defined question.
this is already done; this is what modelling and simulation is for. at least in the US pretty much all projects require some kind of alternatives analysis, and at least one of those alternatives must be "do nothing at all."
whether the model's assumptions are correct, and whether politicians actually allocate funds based on projected efficacy, are another matter entirely.
This is basically impossible to do short of shutting the system down for year to measure the loss (unthinkable).
And even then, you'd have a measurement that doesn't mean anything because it couldn't measure the opportunity costs of the path not taken when the chocie was made initially.
As a matter of fact, I'll go one step further: I don't even think the question makes sense.
Economies are chaotic systems, and even if it is sometimes rather clear after the fact that a specific choice leads to overall positive outcomes (such as choosing to implement a high-quality public transportation system in Switzerland), actually measuring the "gain" is basically impossible. Worse: it's an ill-defined question.