Question 2

In a galaxy far far away, there is a planet called Coruscant with approximately 2 trillion habitants. Scientists are trying to estimate the average distance of this network of people. In a previous study, it was observed that the population can be divided into three groups:
  • 500 billion people know 1000 other people in average;
  • 1 trillion people know 7000 other people in average;
  • 500 billion people know 5000 other people in average;
Which of the following statements are true:

I. Since the network is not random, we cannot estimate the average distance of the network;
II. In real networks, the average distance behaves similar to random networks. In this case, the average distance is approximately 3.3;
III. Considering that the total population is large and that the average degree is relatively low, the degree distribution is well approximated by a Poisson distribution;
IV. The presence of highly connected individuals reduces the average distance in the network.

a) II and III.
b) III and IV.
c) II and IV.
d) I and IV.
e) None of the above.

Original idea by George Gigilas Junior

Comentários

  1. Joao Meidanis21 de março de 2026 às 10:03

    Interesting question, but some of the statements seems dubious. For instance, in III, we are not sure if the author is referring to random networks or not. In II, we are not sure what "behaves similar" really means. I'd rather let it go than risk ambiguity.

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