Airports average distance

The image below shows the complexity of the global airport network. Suppose it is an undirected network with 9033 nodes, that shows the scale-free property, whose exponent degree (γ) changes over time. Considering that in 2022 January, the computed exponent degree (γ) was 2.8 and in February 3.0, please compute the average distances <d> between the airports in both months (round to 3 decimal places):

Image extracted from https://link.springer.com/article/10.1007/s42452-019-0702-2.


A. January <d>: 3.317, February <d>: 4.795

B. January <d>: 2.209 , February <d>: 4.123

C. January <d>: 4.123 , February <d>: 2.209

D. January <d>: 4.795, February <d>: 3.317

E. None of the above.


Original idea by: Felipe Crispim da Rocha Salvagnini








Comentários

  1. Joao Meidanis1 de maio de 2022 às 06:12

    Dear Felipe, I'm not comfortable using approximate formulas such as ~ ln ln N and at the same time ask people to round to 3 decimal places. It gives the wrong impression that the formula computes the actual value, but in fact it just shows the order of growth.

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    Respostas
    1. Felipe Crispim da Rocha Salvagnini1 de maio de 2022 às 17:22

      I see. Would be correct if I have asked for an estimation of the average distances?

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