## The Annals of Applied Probability

### Twitter event networks and the Superstar model

#### Abstract

Condensation phenomenon is often observed in social networks such as Twitter where one “superstar” vertex gains a positive fraction of the edges, while the remaining empirical degree distribution still exhibits a power law tail. We formulate a mathematically tractable model for this phenomenon that provides a better fit to empirical data than the standard preferential attachment model across an array of networks observed in Twitter. Using embeddings in an equivalent continuous time version of the process, and adapting techniques from the stable age-distribution theory of branching processes, we prove limit results for the proportion of edges that condense around the superstar, the degree distribution of the remaining vertices, maximal nonsuperstar degree asymptotics and height of these random trees in the large network limit.

#### Article information

Source
Ann. Appl. Probab., Volume 25, Number 5 (2015), 2462-2502.

Dates
Revised: July 2014
First available in Project Euclid: 30 July 2015

Permanent link to this document
https://projecteuclid.org/euclid.aoap/1438261046

Digital Object Identifier
doi:10.1214/14-AAP1053

Mathematical Reviews number (MathSciNet)
MR3375881

Zentralblatt MATH identifier
1334.60204

#### Citation

Bhamidi, Shankar; Steele, J. Michael; Zaman, Tauhid. Twitter event networks and the Superstar model. Ann. Appl. Probab. 25 (2015), no. 5, 2462--2502. doi:10.1214/14-AAP1053. https://projecteuclid.org/euclid.aoap/1438261046

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