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Efficiency is dangerous and slowing down makes life better

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Re: Efficiency is dangerous and slowing down makes life better

#151

Post by baddox »

didibus wrote: post #130
Taek wrote: post #46

This comment thread is making me realize we don't have a good word to distinguish between efficiency as in "we only have 7 hospital beds because that's all we need on 99% of each day" and efficiency as in "we replaced steps X,Y,Z with just step X', because we found that X' could accomplish everything that XYZ could accomplish but it's faster, more accurate, and cheaper". One makes a tradeoff by reducing overheads and…

We do have a word, it's efficiency and productivity. Efficiency produces the same output with less input. Productivity produces more output with the same input. So efficiency is a measure of input to target output, and productivity is a measure of output to target input. To make a process more efficient, you figure out how to get to some X output while using as little input as possible. To make a process more product…

The first example about hospital capacity really just involves tradeoffs around your specific goals, whereas it only makes sense to talk rigorously about efficiency in the context of some specific output goal.

So if you fix some goal, say, "we want to be over capacity 1% of the time," then the most efficient way of doing that is probably to have the minimum number of beds that you need according to your predictions about utilization. But you can't really talk about efficiency when you're deciding what your goal is, e.g. whether you're okay being over capacity 10% of the time versus 1% of the time.

Re: Efficiency is dangerous and slowing down makes life better

#152

Post by dboreham »

bschne wrote: post #94
jjoonathan wrote: post #54

Earlier quoted context omitted.

It is a fundamental law. Systems theory has the concepts of "gain margin" and "phase margin" -- how much you can amplify feedback or delay feedback, respectively, before your self-adjusting feedback mechanism fails to find equilibrium and turns into an oscillator. Even though most non-engineering systems don't fit the mathematical theory, the idea that only a finite amount of gain + delay is available, and that the t…

Do you happen to know a good introduction to that? I‘d love to read up more on it!

https://books.google.com/books/about/Modern_Control_Theory.h... ?

Re: Efficiency is dangerous and slowing down makes life better

#153

Post by dllthomas »

kazinator wrote: post #116
Taek wrote: post #46

This comment thread is making me realize we don't have a good word to distinguish between efficiency as in "we only have 7 hospital beds because that's all we need on 99% of each day" and efficiency as in "we replaced steps X,Y,Z with just step X', because we found that X' could accomplish everything that XYZ could accomplish but it's faster, more accurate, and cheaper". One makes a tradeoff by reducing overheads and…

There are always tradeoffs. The discovery that X, Y, Z could be replaced by X required investigation, which is a cost, and then changes to be deployed which disruptions that also have a cost. If the deployment of the optimization doesn't recover the costs, then it ends up not worth it. Usually the cost is recouped because the optimization is discovered once, and then deployed on a large scale; but that is not always…

I think considering the cost of change a cost of the optimized version is muddled thinking. It's a cost of deploying the optimized version, but that is only sometimes relevant.

A pure trade-off between efficiency and stability would imply that, were I already running the efficient version, we could buy stability by switching to the less efficient code.

Re: Efficiency is dangerous and slowing down makes life better

#154

Post by gmuslera »

Systems in real life are complex. Limiting them to just one dimension on which they are efficient may leave out factors that make them work at all, or just better.

But if you really know every and all components and criteria that may be applied to them, you might improve efficience. Good luck with that.

Re: Efficiency is dangerous and slowing down makes life better

#155

Post by aaron-santos »

aaron-santos wrote: post #51
MadSudaca wrote: post #20

Earlier quoted context omitted.

Maybe the problem is that efficiency and robustness are orthogonal?

If you think about the two-dimensional efficiency/robustness space you can pretty easily see how it's isomorphic to the return/volatility space by way of simple transformations. If yourself to be convinced that such a bridge exists you can also bring tools in the return/volatility space back into the efficiency/robustness space by applying the appropriate inverse transformations. Maybe the conclusions are common sens…

EDIT: If you allow yourself.. :/

Re: Efficiency is dangerous and slowing down makes life better

#156

Post by TheOtherHobbes »

nitrogen wrote: post #31
alexpetralia wrote: post #4

Earlier quoted context omitted.

I think this is probably better characterized as "efficiency erodes resilience". You can have stability if there are no perturbations. However, if there are, and you have optimized for a regime where there are not, you are very exposed to risk. This is pretty much Table's notion of antifragility as well as the study of resilience engineering.

There's an engineering version of "stable" that might be useful here to draw lines between the three or so different concepts being discussed. A "stable" system is one that will return to the same resting state when perturbed. One can have "equilibrium" in an unstable system, e.g. balancing a broomstick on one's hand, but the system will not return to that equilibrium if perturbed.

It's not a binary opposition. In control theory you can make a system unconditionally stable, or you can allow a little oscillation around the ideal, or you can make it unconditionally unstable so the tiniest hint of noise drives it to an extreme.

In some systems you want to generate constant oscillations, so your system can be in stable perpetual dynamic equilibrium producing a nice sine wave.

Re: Efficiency is dangerous and slowing down makes life better

#157

Post by roughly »

dependsontheq wrote: post #138
roughly wrote: post #128

Earlier quoted context omitted.

> Fragile systems are often very successful for a long time because they ignore hidden risks and then collapse due to the unexpected. There's another interesting aspect to this in that things that are failures from some perspectives may not be from others. If stripping resiliency out of a company nets enough savings in the short term, it may still be profitable to the owners it even if it's long-term fatal. As a hypo…

Only if you define local interest as purely financially motivated. I am not even talking about the ethics, but even social status is not only dependent on wealth. We are much more than a bank account number, thinking that we are is more or less a pathological disease, because rationally it makes no sense.

> Only if you define local interest as purely financially motivated social status is not only dependent on wealth

For an awful lot of people, it basically is - I mean, practically the entire field of finance and professional management would look at the example I gave and say, "that's exactly the right thing to do." Mitt Romney's entire professional career follows that principle, and it's largely seen as a net positive to his political career (as a Republican).

I agree with you, I think it's an enormously damaging philosophy, both to the bearer and to the rest of us, but again, it may be locally optimal.

Re: Efficiency is dangerous and slowing down makes life better

#158

Post by p-funk »

bschne wrote: post #94
jjoonathan wrote: post #54

Earlier quoted context omitted.

It is a fundamental law. Systems theory has the concepts of "gain margin" and "phase margin" -- how much you can amplify feedback or delay feedback, respectively, before your self-adjusting feedback mechanism fails to find equilibrium and turns into an oscillator. Even though most non-engineering systems don't fit the mathematical theory, the idea that only a finite amount of gain + delay is available, and that the t…

Do you happen to know a good introduction to that? I‘d love to read up more on it!

This youtube channel has (seemingly good quality) Khan Academy style lecture videos on control systems, if you just want a quick introduction to the concepts.

https://www.youtube.com/watch?v=ThoA4amCAX4

Re: Efficiency is dangerous and slowing down makes life better

#159

Post by brlewis »

pdonis wrote: post #85
pottertheotter wrote: post #75

Earlier quoted context omitted.

It's the same with the lottery. If you understand that the cash expected value is lower than the cost of the ticket, but you get some value from having "played" and the net is at least equal to the price of the ticket, it's not irrational to buy a lottery ticket.

This is true, but the kind of value being provided is different. Peace of mind is not the same thing as entertainment.

Maybe you all can agree that insurance and lottery are the same in that only a fraction of consumers come out ahead, and are opposites in terms of smart vs. stupid.

Re: Efficiency is dangerous and slowing down makes life better

#160

Post by rdtwo »

SlavikCA wrote: post #122
rdtwo wrote: post #119

Earlier quoted context omitted.

Usually they have wipeout problems that can’t be insured for. Medical conditions or unemployment being the most common.

Can't be insured for? I find that ironic, because we actually have medical insurance and unemployment insurance here in USA, but we often see "individuals with limited resources" wiped out for reasons you mentioned.

In areas where that works it’s more of a social insurance and government run. In the us medical insurance is a rate subscription service, similar to say Costco.
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