Global optimization vs. Local optimization

Donがつぶやいた全体最適vs.部分最適の話題について、Alanが反応していたので自分用のメモとして保存。 併せてその後のDonと何人かのやりとりも収録。
Donald Reinertsen @DReinertsen

Global optimization vs. Local optimization. Compare the promise and reality of centrally planned economies vs. markets. 1/3

2010-04-28 22:33:22
Donald Reinertsen @DReinertsen

Global optimization can be exponentially more difficult and is more perishable, only briefly valid 2/3

2010-04-28 22:37:31
Donald Reinertsen @DReinertsen

Local optimization should be in the toolkit of any lean thinker. It can be closer to the true spirit of lean than system thinking. 3/3

2010-04-28 22:40:38
Al Shalloway Closing the gap between known & used @alshalloway

@DReinertsen power of flow is you can do local optimizations w/ confidence you are helping the whole

2010-04-28 22:44:24
Al Shalloway Closing the gap between known & used @alshalloway

@DReinertsen w/o understanding principles local optimizations can have adverse affect on entire Value stream

2010-04-28 22:45:40
Akbar Zamir @akbarzamir

@DReinertsen What about insights from Op Research, the beer game and such? Local optimisation in that supply chain seems problematic.

2010-04-28 22:46:39
Akbar Zamir @akbarzamir

@DReinertsen Or is it rather a question of *which* local property we choose to optimise?

2010-04-28 22:48:26
Donald Reinertsen @DReinertsen

@akbarzamir I am in favor of having both tools available and fitting to context. Beer game is simple but illustrates time lags well.

2010-04-28 22:52:49
Alina Hsu @alinahsu

@DReinertsen IME global optimization is more a matter of using balanced whole-system metrics than of central planning.

2010-04-28 22:54:16
Donald Reinertsen @DReinertsen

@akbarzamir IMO it is smart, but not really global optimization, when you start dropping parameters from your target performance function.

2010-04-28 22:56:55
Akbar Zamir @akbarzamir

@DReinertsen I guess I'd expect a greater lag in feedback when monitoring system rather than local parameter.

2010-04-28 22:59:34
Niklas Björnerstedt @smalltalk80

.@DReinertsen Global optimization by top down management is not Systems thinking.

2010-04-28 23:04:25
Donald Reinertsen @DReinertsen

@alinahsu In world where local optimization is unfashionable we could call choosing a subset of metrics to optimize "global optimization".

2010-04-28 23:09:05
Donald Reinertsen @DReinertsen

@smalltalk80 It is probably not really optimized if top down. I see global optimization as state variable, ie path-independent.

2010-04-28 23:19:31
Donald Reinertsen @DReinertsen

@akbarzamir A good example of this is how local WIP control loop of kanban can be 100x faster than the more global WIP constraint of TOC.

2010-04-29 02:07:45
Niklas Björnerstedt @smalltalk80

.@DReinertsen The point is that systems thinking is about more than a systems optimum. It is also about the right way of achieving it.

2010-04-29 03:34:28