Power law

  • Article
    | Open Access

    According to Zipf’s law, the population size of a city is inversely proportional to its size rank in any urban system. The authors show how demography explains this law as a time average of balanced migration between cities and how deviations express information about people’s net preferences.

    • Luís M. A. Bettencourt
    •  & Daniel Zünd
  • Article
    | Open Access

    Real-world networks are often said to be ”scale free”, meaning their degree distribution follows a power law. Broido and Clauset perform statistical tests of this claim using a large and diverse corpus of real-world networks, showing that scale-free structure is far from universal.

    • Anna D. Broido
    •  & Aaron Clauset
  • Article |

    Understanding the environmental controls of past wildfires is difficult due to the lack of records of weather or vegetation. This study shows, using cross-scale analysis, how power laws associated with fire-event time series can identify critical thresholds in landscape dynamics in a rapidly changing climate.

    • Donald McKenzie
    •  & Maureen C. Kennedy