Co-stardom network

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In social network analysis, the co-stardom network represents the collaboration graph of film actors i.e. movie stars. The co-stardom network can be represented by an undirected graph of nodes and links. Nodes correspond to the movie star actors and two nodes are linked if they co-starred (performed) in the same movie. The links are un-directed, and can be weighted or not depending on the goals of study. If the number of times two actors appeared in a movie is needed, links are assigned weights. [1] The co-stardom network can also be represented by a bipartite graph where nodes are of two types: actors and movies. And edges connect different types of nodes (i.e. actors to movies) if they have a relationship (actors in a movie). [2] Initially the network was found to have a small-world property. [3] Afterwards, it was discovered that it exhibits a scale-free (power-law) behavior. [4]

Contents

The parlor game of Six Degrees of Kevin Bacon involves finding paths in this network from specified actors to Kevin Bacon.

Network representation

In order to represent any network, it is necessary to characterize the properties of the corresponding graph of nodes and links. Studies on the collaboration network of movie actors have been described in literature such as the work done by (Watts and Strogatz, 1998), and Barabási and Albert in (1999) and (2000). The general characteristics are described below. [5] [6] [7] [8] [9]

Size: 225 226
Average degree: 61
Average path length: 3.65
Clustering coefficient: 0.79

Compared to a random graph of the same size and average degree, the average path length is close in value. However, the clustering coefficient is much higher for the movie actor network.

Size: 212 250
Average degree: 28.78
Cutoff for power-law scaling: 900
Clustering coefficient: 0.79

Therefore, the underlying network has the scale-free degree distribution p(k) ~ kγactor, with an exponent γactor = 2.3 ± 0.1 (Barabási and Albert, 1999), (Albert and Barabási, 2000).

Data collection

The Internet Movie Database IMDB represents one of the largest internet sources for movies/actors data. And it is where most of the datasets are collected to study the collaboration network of co-star actors. IMDB facilitates the ability to collect data for very specific and variable types of network. For example, a network can be constructed using data from all the horror movies made within a specific time period (ex. 2000–2010) and only picking the top three co-stars in each movie.

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References

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