Trust me, I am Famous. A study on the effects of YouTube metrics and review valence on perceived source credibility and purchase intention.

The changes that Web 2.0 brought to people’s lives in the past years have also introduced a lot of changes in several industries. Especially social media have disrupted the ways of interaction within societies, interpersonal relations, as well as communication and advertising in numerous fields. Likewise, a new landscape has been created, that nowadays hosts the actions that in the past would have mainly taken place in the outside world or through traditional media. This thesis attempted to research the effects of technology product review videos on YouTube, the leading social medium when it comes to video hosting. Using YouTube’s environment, an online experimental survey was conducted. The goal was to understand the effect of YouTube’s popularity metrics that exist for every video and channel, together with those of review valence, on the perceived information credibility and purchase intention of the audience. The experimental part of the research helped in revealing cause-effect relationships, as well as joint effects from the manipulations on the dependent variables. The results from the data analysis were both expected and surprising. They partly confirmed past literature regarding the effects of social media metrics, that were found to positively affect both credibility and purchase intention. As long as review valence is concerned, the findings were in contrast with what has been demonstrated in past studies, showing no effect on either of the two dependent variables. Interestingly, the only joint effect that was found was from the combination of positive valence with low metrics on the trustworthiness of the source and the information as perceived by the participants. The findings are finally discussed through the scope of the Heuristic-Systematic model of information processing in order to provide a better understanding of the motives and reasons behind them.