Thursday, November 1, 2018

Only the Big Ideas #7 — Overconfidence, Percolation, DevOps metrics, Self-Improvement






Surfacing mental models, weekly
Read 3 articles and listen to 1 podcast to learn 15 mental models this week, including:

  • Explosive percolation
  • Cascading failure
  • Criticality
  • Mean time to recovery (MTTR)
  • Disturbance propagation
  • Dissipative systems
  • Overconfidence

The Three Faces of Overconfidence

The belief that we can perform at a level beyond that which we realistically can (Overconfident about overconfidence)
The erroneous relative judgment that we are better than others (Overconfident about overconfidence)
Overprecision is the tendency to believe that our predictions or estimates are more accurate than they actually are (Overconfident about overconfidence)





Quanta Magazine — The New Laws of Explosive Networks

The emergence of large-scale connectivity on an underlying network or lattice (Anomalous critical and supercritical phenomena in explosive percolation)
“Instead of [of a phase transition] arising from a slow, steady continuous march toward greater and greater connectivity, connections emerge globally all at once throughout the system in a kind of explosion”
another take: Explosive percolation describes the abrupt onset of large-scale connectivity that results from a simple random process designed to delay the onset of the transition on an underlying random network or lattice (Explosive Percolation: Novel critical and supercritical phenomena)
During a phase transition of a given medium, certain properties of the medium change, often discontinuously, as a result of the change of some external condition, such as temperature, pressure, or others (Wikipedia)
A process in which the failure of any component of a system increases pressure on other components, leading to their failure. Cascading failure is a common failure mode for many types of systems in which components are highly interconnected (Santa Fe Institute Glossary)
Criticality is a concept taken from nuclear engineering in which fissionable material is brought together in enough quantity to start a chain reaction (Santa Fe Institute Glossary)
another take: In thermodynamics, a critical point (or critical state) is the end point of a phase equilibrium curve. The most prominent example is the liquid-vapor critical point, the end point of the pressure-temperature curve that designates conditions under which a liquid and its vapor can coexist. (Wikipedia — Critical Point)





a16z — Feedback Loops — Company Culture, Change, and DevOps (Podcast)

The average time that a device will take to recover from any failure (Wikipedia)
MTBF can be calculated as the average time between failures of a system. The term is used for repairable systems, while mean time to failure (MTTF) denotes the expected time to failure for a non-repairable system (Wikipedia)
The ratio of new features to failures in production (DevOps KPI in Practice)
The amount of time that occurs between starting on a work item until it is deployed (Stackify)





Ribbon Farm — The Holy Grail of Self-Improvement

A process by which a system of interacting subunits acquires qualitatively new properties that cannot be understood as the simple addition of their individual contributions (Sante Fe Institute Glossary)
“The whole is other than the sum of its parts” (Nicky Case)
The way in which a small disturbance acting on one node within a system can travel throughout the system, effecting other nodes (Adapted from: Disturbance propagation in vehicle strings)
another take: The key point is that extending solutions based on a single node can lead to unintended problems on a macro level. Thus, control structures with only local information fail to be scalable.
The problem can be solved if we include reference information in the control structure (Adapted from: Disturbance propagation in large interconnected systems)
Dissipative structures are nonequilibrium thermodynamic systems that generate order spontaneously by exchanging energy with their external environments. Dissipative structures include physical processes (e.g., whirlpools), chemical reactions (e.g., Bénard cell convection), and biological systems (e.g., cells) (Encyclopedia.com)
A dissipative structure is characterized by the spontaneous appearance of symmetry breaking and the formation of complex, sometimes chaotic, structures where interacting particles exhibit long range correlations