Social Presence

In the article, Gunawardena concludes by saying that instructors need to learn to adapt to telecommunications media by developing interaction skills that create a sense of social presence. What are these interaction skills that can impact students' perception of interaction and social presence?

How can instructors increase social presence to positively impact students' learning in online environments?

Reputation and Trust

In Six degrees of reputation David and Pinch mention both advantages and disadvantages of online review and recommendation systems. My questions is: How can we trust the authenticity of a reviews on any review system? How can the reliability of reputation systems be improved?