Friday, February 1, 2013

On preventing randomness


In his new book on fragile -- and antifragile -- systems, Nassim Taleb makes this point, somewhat striking on first read:
You can't prevent randomness by removing randomness
What's he trying to say here? Two things really:

1. Abstracting underlying randomness and uncertainty into something smooth and somewhat unchanging doesn't really change the nature of the underlying circumstances; it changes your view, perception, or awareness only. And, if you're looking only at the average of the underlying uncertainty -- not really an abstraction, but nonetheless an obscurring of detail -- then  effectively the Central Limit Theorem (CLT) is at work


2. Although abstraction and central tendency smooth thing out, Taleb's point is that there can still be a random shock. You're fooling yourself if you think it can't happen because of all your smoothing strategies.  In other words: the absence of evidence is not evidence of absence! We can roll right up to a calamitous event without forewarning... like the turkey on Thanksgiving

Consider this: if a number of smaller perturbations should add up coherently -- as they sometimes do in complex systems with chaotic or emergent properties -- then smooth may abruptly turn into a big discontinuity or a big bang.

Example: the white noise of a bunch of people chattering in a crowd will sound much different than the same people talking (or singing) in unison... coherently adding their voices. There will be big highs and big lows as their voices join, whereas the crowd noise is almost uniform forever until something causes the crowd to become a chorus.

To some extent this is an example of domination: the chorus is likely to have a more dominant influence than the white noise of the crowd.

In Taleb's recipe, systems/processes/projects/enterprises may actually be more fragile -- susceptible to failure due to shock -- for having smoothed it all out, only to have a shocking bang -- than are those who maintain a keen awareness of the underlying disturbances.

Said another way: shock -- the rare event -- may dominate success or even survival.

Large and central
Taleb suggests that the larger and more centralized is an entity the more it is susceptible to unwitting fragility -- tendency to fail with shock. This is because there is no ongoing learning and practice for dealing with shock. More decentralized entities have more randomness, less smoothing, and thus more developed strategies for dealing with the randomness.  Think of driving to work everyday and learning to deal with that troublesome intersection.

And, think of the low-level work package manager who experiences much more randomness that the overall project manager. The WP manager may actually have a more refined ability to work with randomness than the more centralized PM.

In political terms, applicable to either private or public entities, "empires" are generally loosely coupled and highly decentralized, immunizing them from large shocks; whereas "nations" are governed centrally and impose an overhead to

Smaller is better, and so also decentralization
So, we come to things like agile, that emphasize the tactics of small unit teams, flat organizations that prevent hiding in the bureauracy, and democratic tools like social networking and email. They all propagate randomness rather than preventing it.