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Musings on Metrics for Service Systems Scott N. Gerard, PhD [email protected]
13

Musings on Metrics for Service Systems

Feb 18, 2017

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Page 1: Musings on Metrics for Service Systems

Musings on

Metrics for Service Systems

Scott N. Gerard, PhD

[email protected]

Page 2: Musings on Metrics for Service Systems

Chaisson, Cosmic Evolution,

Harvard Univ Press, 2001

Page 3: Musings on Metrics for Service Systems
Page 4: Musings on Metrics for Service Systems

Cosmic Evolution’s Basic Premise

• 2nd Law of Thermodynamics, Entropy, Free energy (available to do work)

• Systems with “dynamic steady state” are far from thermodynamic

equilibrium

• Systems feed off energy flow

• More complex systems require larger energy flow

• Chaisson’s primary metric is “free energy rate density”

lake

river

total energyentropy

free energy

dam

system

Page 5: Musings on Metrics for Service Systems

Hidden Assumption

≠?

• Evolved systems are likely relatively efficient

• Are (new) man-made service systems equally efficient ?

Actual

Energy

Minimal

EnergyComplexity

inefficient ?

measure

Actual

Energy

Minimal

EnergyComplexity

efficient

measure

proportionalEvolved

Systems

Human

Systems

assumed proportional

assumed proportional

Page 6: Musings on Metrics for Service Systems

Free Energy Rate Density

Measurements

System Energy Flow Mass erg/sec/g

civilization (society) 18 trillion watts 6 billion

inhabitants

500,000

animal (human body) 2800 kcal/day =

1.36E9 erg/sec

70 kg =

70,000 g

20,000

star (Sun) luminosity=

4E33 erg/sec

mass=

2E33 g

2

Page 7: Musings on Metrics for Service Systems

Free Energy Rate Density

Measurements

System erg/sec/g

society (modern culture) 500,000

brain (human cranium) 150,000

animal (human body) 20,000

plant (biosphere) 900

planet (Earth) 75

star (Sun) 2

galaxy (Milky Way) 0.5

Page 8: Musings on Metrics for Service Systems

Free Energy Rate Density

for Service Systems

System erg/sec/g

society (modern culture) 500,000

United States Government ?

Hilton Hotel (chain) ?

McDonalds (chain) ?

sports complex ?

single site restaurant ?

Salvation Army ?

Boy Scouts ?

single family household ?

others ?

brains (human cranium) 150,000

animals (human body) 20,000

Page 9: Musings on Metrics for Service Systems

Service Metric Possibilitiesdriver rate density

free energy per second per gram

information

information (entropy)

bits of client insight

service hours of op

consumer hours of op

total service knowledge (bits)

size of data stores

value

service’s utility

client’s utility

money

revenue

after-tax revenue

book/liquidation value

market value

Ph

ysic

al

Info

rma

tio

na

lF

ina

nci

al

Va

lue

Page 10: Musings on Metrics for Service Systems

Related Works

• Prigogine, From Being to Becoming: Time and Complexity in the Physical Sciences, Freeman, 1980.

– Winner of 1977 Nobel Prize in Chemistry

– discusses dissipative structures and their role in thermodynamic systems far from equilibrium

– how systems far from equilibrium evolve elaborate structures

• Tainter, The Collapse of Complex Societies, Cambridge, 2013. – “Human societies and political organizations, like all living systems, are

maintained by a continuous flow of energy”

– “diminishing returns … are a recurrent aspect of sociopolitical evolution, and of investment in complexity”

– “the increased costs of sociopolitical evolution frequently reach a point of diminishing marginal returns”

Page 11: Musings on Metrics for Service Systems

BACKUP

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