Primate City Rank Size Zipf
Apply the Zipf rank-size rule P(n) = P(1) / n^q to predict the population of the n-th largest city from the primate city, optionally reporting how far an observed city deviates from that prediction.
Description
Apply the Zipf rank-size rule P(n) = P(1) / n^q to predict the population of the n-th largest city from the primate city, optionally reporting how far an observed city deviates from that prediction.
Apply the Zipf rank-size rule P(n) = P(1) / n^q to predict the population of the n-th largest city from the primate city, optionally reporting how far an observed city deviates from that prediction.1
When to use Primate City Rank Size Zipf
Use this measure when city ranks, urban shares, or rural-urban classifications use consistent boundaries and reference years.
- P1
- Population of the largest (primate) city.
- Rank
- Rank of the city being evaluated.
- Exponent q
- Rank-size exponent q; one is Zipf's law.
- Actual
- Observed population of the ranked city, when known.
How the method works
- Prediction
- Predicted population of the ranked city under the rule.
- Deviation %
- Observed minus predicted as percent of prediction; zero when no observed value is supplied.
Limitations and assumptions
Urban definitions and administrative boundaries differ widely. Annexation, metropolitan definitions, and changes in settlement classification can mimic population change.
Alternative or Complementary measures
Pair shares or rank-size results with absolute population changes under fixed geographic boundaries. Density, commuting zones, and settlement classifications offer complementary views of urban concentration.
References
-
Urbanization — Wikipedia contributors
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