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Published equation contexts

gA=λn1−ϕg_A = \frac{\lambda n}{1-\phi}

Why this formula appears here

Semi-endogenous growth theory, the framework Jones developed and that his 2022 Annual Review of Economics piece surveys, formalizes this into a relationship between population growth and the long-run growth rate of ideas [ 4 ] . Population enters the idea-production function as the stock of people available to search the technological fitness landscape for improvements, and because ideas are non-rival — one firm’s discovery of a better transistor layout does not use up the possibility for another firm to discover a different one — expanding that search population raises the rate of discovery roughly in proportion to its own growth, discounted by how much duplicated effort dilutes the return…

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ϕ\phi

Symbol phi

phi occurs below the fraction bar. The quantity above the bar is divided by this expression; zero is excluded as a denominator.

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How to interpret it

With a fixed numerator, increasing a nonzero denominator reduces the fraction. Read it with the definitions, units, and assumptions supplied by the article.

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Published contexts (1)

A symbol can carry a different meaning in another article. Each occurrence keeps its own guide and term definitions.

gA=λn1−ϕg_A = \frac{\lambda n}{1-\phi}

Equation 1 · Technological Evolution

Who Builds 2100? The Demographic Engine of Technological Evolution

This equation states an equality: the expressions on both sides have the same value under the article’s assumptions.

Semi-endogenous growth theory, the framework Jones developed and that his 2022 Annual Review of Economics piece surveys, formalizes this into a relationship between population growth and the long-run growth rate of ideas [ 4 ] . Population enters the idea-production function as the stock of people available to search the technological fitness landscape for improvements, and because ideas are non-rival — one firm’s discovery of a better transistor layout does not use up the possibility for another firm to discover a different one — expanding that search population raises the rate of discovery roughly in proportion to its own growth, discounted by how much duplicated effort dilutes the return…

Meanings in this article

  • gAg_A: the canonical form of the relationship.
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