# How the Avengers assemble: Ecological modelling of effective cast sizes for movies

## TL;DR

This paper introduces an ecological diversity-based metric to quantify and compare the cast sizes of movies, providing insights into franchise success and character relationships, with applications in classification and recommendation systems.

## Contribution

It proposes a Shannon-entropy and Jensen-Shannon divergence-based metric for character analysis in movies, offering a novel approach to understanding cast complexity and inter-movie similarities.

## Key findings

- The metric effectively characterizes movie cast diversity.
- It predicts film success within the MCU.
- It reveals relationships between story arcs.

## Abstract

The number of characters in a movie is an interesting feature. However, it is non-trivial to measure directly. Naive metrics such as the number of credited characters vary wildly. Here, we show that a metric based on the notion of "ecological diversity" as expressed through a Shannon-entropy based metric can characterise the number of characters in a movie, and is useful in taxonomic classification. We also show how the metric can be generalised using Jensen-Shannon divergence to provide a measure of the similarity of characters appearing in different movies, for instance of use in recommender systems, e.g., Netflix. We apply our measures to the Marvel Cinematic Universe (MCU), and show what they teach us about this highly successful franchise of movies. In particular, these measures provide a useful predictor of "success" for films in the MCU, as well as a natural means to understand the relationships between the stories in the overall film arc.