Media and Communication Ph.D. Dissertations


How Do Credibility of For-profit and Non-profit Source and Sharer, Emotion Valence, Message Elaboration, and Issue Controversiality Influence Message Sharing to Imagined Audience on Facebook?

Date of Award


Document Type


Degree Name

Doctor of Philosophy (Ph.D.)


Media and Communication

First Advisor

Louisa Ha (Advisor)

Second Advisor

Frederick Busselle (Committee Member)

Third Advisor

Yanqin Lu (Committee Member)

Fourth Advisor

Sean Leatherbury (Other)


Sharing, a term that is associated with “going viral,” is something all strategic communicators strive for in their communication campaigns. The current study explored sharing as message diffusion. The nature of information sharing is perceived as a form of word-of-mouth (WOM)—a voluntary act by the consumers to tell others their experience of a product or consumption of certain information. Sharing is an important social and economic phenomenon to study, because it maximizes the visibility of a company, a brand, a nonprofit, a policy, a product, and a service.

This study aimed to create a comprehensive model explaining the process of individuals’ decisions in the sharing of messages to their imagined audience on social media through considering the primary and secondary sources of the messages, their perceived credibility, emotion valence, and elaboration of the messages, while controlling audience variables such as issue involvement, personalities, past sharing experience, and demographics.

The researcher conducted a two-wave experiment with a two by two factorial design. The study adopted Facebook as the subject of study. According to the results, when the original source is a for-profit organization, the post from the two-layered source is more likely to be shared than original source only. However, when the original source is a non-profit organization, the post from the direct source was more likely to be shared than a two-layered source. In addition, sharer credibility moderates the effects of the credibility of original sources on sharing Facebook posts. Message elaboration mediates the effects of both positive and negative emotion arousal on sharing non-controversial issues, but not in controversial issues. Furthermore, positive emotions were directly and indirectly associated with sharing non-controversial issues through a mediator of message elaboration that is conditioned by sharer credibility.

This study advances and contributes ELM, the Two-Step Flow Theory, and demonstrates the merit of multi-stimuli experimental design. It also provides practical implications for strategic communicators on how messages can be diffused and spread to a wider audience based on their organization credibility and general source cue as for-profit or non-profit organizations.