You are provided with the abstract of a scientific paper and the abstracts of the papers it references. Your task is to write a Related Work section for the main paper. This section should concisely summarize and integrate the key points from the cited abstracts, reflecting how they relate to the main paper's contributions and context. In your summary, use numerical citation markers like [1], [2], etc., to refer to the corresponding papers.

Main Abstract:
Internet social networks have become a ubiquitous application allowing people to easily share text, pictures, and audio and video files. Popular networks include WhatsApp, Facebook, Reddit and LinkedIn. We present an extensive study of the usage of the WhatsApp social network, an Internet messaging application that is quickly replacing SMS messaging. In order to better understand people's use of the network, we provide an analysis of over 6 million messages from over 100 users, with the objective of building demographic prediction models using activity data. We performed extensive statistical and numerical analysis of the data and found significant differences in WhatsApp usage across people of different genders and ages. We also inputted the data into the Weka data mining package and studied models created from decision tree and Bayesian network algorithms. We found that different genders and age demographics had significantly different usage habits in almost all message and group attributes. We also noted differences in users' group behavior and created prediction models, including the likelihood a given group would have relatively more file attachments, if a group would contain a larger number of participants, a higher frequency of activity, quicker response times and shorter messages. We were successful in quantifying and predicting a user's gender and age demographic. Similarly, we were able to predict different types of group usage. All models were built without analyzing message content. We present a detailed discussion about the specific attributes that were contained in all predictive models and suggest possible applications based on these results.

Cited Abstract(s):
[1]: 

[2]: Although both men and women communicate frequently on Facebook, we know little about what they talk about, whether their topics differ and how their network responds. Using Latent Dirichlet Allocation (LDA), we identify topics from more than half a million Facebook status updates and determine which topics are more likely to receive feedback, such as likes and comments. Women tend to share more personal topics (e.g., family matters), while men discuss more public ones (e.g., politics and sports). Generally, women receive more feedback than men, but "male" topics (those more often posted by men) receive more feedback, especially when posted by women.

[3]: Wikipedia is a community-created encyclopedia that contains information about notable people from different countries, epochs and disciplines and aims to document the world's knowledge from a neutral point of view. However, the narrow diversity of the Wikipedia editor community has the potential to introduce systemic biases such as gender biases into the content of Wikipedia. In this paper we aim to tackle a sub problem of this larger challenge by presenting and applying a computational method for assessing gender bias on Wikipedia along multiple dimensions. We find that while women on Wikipedia are covered and featured well in many Wikipedia language editions, the way women are portrayed starkly differs from the way men are portrayed. We hope our work contributes to increasing awareness about gender biases online, and in particular to raising attention to the different levels in which gender biases can manifest themselves on the web.
In theory, even more accurate models could have been constructed had we also analyzed the messages' content. Specifically, models have been previously developed which can predict an author's gender, age, native language or personality [2] [1] based on content. Examples include work by Argamon [1] which focused on creating models that identify word usage differences between men and women on Internet blogs. Similarly, Wagner et. al [3] focused on content differences between men and women in Wikipedia, and Wang, Burke and Kraut performed a study of content differences between genders on Facebook [2] . However, as the WhatsApp network is inherently private, such approaches could not be applied in our case due to privacy concerns. As we now detail, even despite not having this information we were indeed similarly successful in predicting a user's demographic and group behavior.