Measuring the Influence of Dynamically Created Virtual Communities Anchored around Hashtags Somprakash Bandyopadhyay Management Information Systems Group, Indian Institute of Calcutta, India (somprakash@iimcal.ac.in ) Sudipa Batabyal Cognizant Technology Solutions, Kolkata, India (sudipa.batabyal@gmail.com ) Somsukla Banerjee Social Informatics Research Group, Indian Institute of Calcutta, India. (somsukla2005@gmail.com ) Rituparna Malik Indian Institute of Management Bangalore (rituparna.malik15@iimb.ernet.in ) ABSTRACT In recent times, advances in internet technology have made it possible to create online social spaces and communities transcending geographical boundaries. Such communities are called 'virtual' as they are not tied to any particular location and allow individuals to interact through social media in order to pursue mutual interests and growths. In-depth understanding of virtual community dynamics help us to address questions of collaboration and knowledge sharing in these spaces. The objective of this paper is to study how special purpose virtual communities are spontaneously formed and evolved using the #hashtag symbol along with a key word or phrase. Creation of this type of powerful special purpose, virtual communities has positive social implications in enhancing social capital and civic engagement. For example, creating a dynamic virtual community anchored around a hashtag (e.g. #Uttarakhand) helps in situation analysis and facilitates disaster recovery. This paper analyzes how contextual hashtags lead to the creation to dynamic virtual communities and proposes a technique to determine a CommunityScore (similar in nature to Klout score, but in the context of virtual community) that determines the influence and strength of a virtual community Keywords: Hashtag; Virtual community; Klout score; Social capital INTRODUCTION Social-media platforms have changed the nature of Web-based communication, transforming the Internet into a realm that is both participatory and conversational [1]. Virtual communities that use social-media platforms allow for connection, communication, and collaboration to take place between users on a grand scale [2]. The use of the “hashtag” symbol is a well-established practice in social networking sites such as Twitter, Facebook to express and/or contribute about an event or experience. The hashtags enable to create and anchor a “special-purpose”virtual community around a particular topic or interest. It is possible for people across the globe to use social