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Equation 4 · Part 1 · The Metabolism of Civilization: Energy to 2100

Symbol z_0

z0z_0
z0z_0

What this part means

z0z_0 is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

Its job in the formula

z0z_0 is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

The passage around this formula

The formal relationship goes back to Theodore Wright’s 1936 observation that aircraft manufacturing labor hours fell as a power-law function of the number of airframes already built, and Way et al. build their entire forecasting method on a stochastic version of it, fitted to more than fifty technologies’ historical cost and production records [ 1 ] . Written in its cleanest form, cost c at cumulative production (experience) z relates to a reference cost c0c_0 at reference experience z0z_0 by:

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A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.

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Sources cited in the surrounding passage

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