weak ties walter Values and Technology values turkle Trust Telephone Technological determinism Tacit Knowledge tacit Social Network social media SCOT ryan Reputation quantitative methods quantitative Qualitative methods qualitative Online Reputation Systems online identity online games One laptop per child OLPC Notification Norms notification Nissenbaum networks music motivation L28 L27 L25 L24 L23 L21 L19 L15 L13 L11 L10 L8 L5 L3 intrinsic motivation internet Identity homophily Heilbroner Frey Fischer facebook extrinsic motivation Ethnography Diffusion design crowdsourcing credibility badges ANT