Barrie Gunter, in his book News and the Net, defines interactivity, in the context of online journalism, by enumerating four dimensions that make a news site interactive:
1. Complexity of choice offered to users. Interactivity is conceived of of as the range, or complexity, of content topics and content-interaction devices that Web journalists offer their audiences. The assumption is that consumers will experience greater interactivity when more choice is provided.
2. Responsiveness to the user. Online journalism offers interpersonal interactivity when Web journalists engage individual audience members through the Internet’s technology. This kind of communication would be asynchronous, or delayed, as is the case with the e-mail.
3. Facilitation of interpersonal communication. Interactivity, for this dimension, could be thought of as asynchronous, or in real time, conversation. Online journalists would facilitate this by allowing their Web sites to be used as conduits through which two audience members could engage each other interpersonally.
4. Ease of adding information to the system. Another way to conceive of Web journalism’s interactivity is whether content consumers are permitted to add their own messages to the news site. In this way, they become content producers as well as consumers of it. The interaction would be asynchronous and from one member of an audience to the many members.
These four dimensions were derived from the conceptual model of interactivity developed earlier by Heeter (1989). The model, in its original form, has six dimensions but those four mentioned above, according to Gunter, were regarded as directly relevant to the analysis of online news.
Aside from these four dimensions, Gunter also writes about a fifth one – immediacy – added by Massey and Levy (1998), who define it as “the extent to which Web news sites provide consumers with the most immediately available information.”