We get to know people by gaining knowledge about them, such as talking to them, talking to others about them, or observing how they react in certain situations. This is known as the uncertainty reduction process in interpersonal communication. In the contemporary media environment, what people publish about themselves on social network sites (SNSs) provides information seekers with plenty of knowledge about the person. Previous research, however, showed that the SNSs information did not help an information seeker reduce uncertainties or feel closer to a person as much as directly interacting with the person.

To explain this, previous research proposed a distinction between interpersonal and personal knowledge. Personal knowledge refers to how a target person feels, thinks, and behaves in certain situations. Interpersonal knowledge, on the other hand, refers to how a target reacts to an information seeker in a unique fashion different from how the target responds to others. It is argued that interpersonal knowledge can only be gained from direct interactions and it is the kind of knowledge that ultimately makes up the essence of affinity and intimacy.

To answer further inquiries about how the information one can find about a target online contributes to an information seeker’s personal and interpersonal certainties about the target, Dr Nancy DAI Yue, Assistant Professor of CityU’s Department of Media and Communication, led a research project to investigate how the information seeker’s interpersonal and personal certainties about a target person were influenced by (1) positive and negative information on SNSs about a target person, (2) the source of the information, and (3) an information seeker’s positivism bias in interpersonal interactions. It is the first empirical attempt to separate interpersonal and personal certainties in person perception.

The research team designed an experiment to verify if interpersonal and personal knowledge were indeed separate concepts in the impression formation process and how different types of information on one’s SNS influenced both. The experiment was carried out by showing participants different versions of a fictitious target’s social media profile that varied in 1) whether it gave positive or negative descriptions about the target person and 2) whether the information was written by the target person or a third party.

Dai and her research partner discovered the following findings. First, reading SNS information about a person increased personal certainty more than interpersonal certainty, regardless of whether the information posted by the target person or a third party. Second, reading negative information about the target increased the information seeker’s interpersonal knowledge about the target more than positive information, but this did not occur for people who had a higher confidence in being liked by others in social interactions. In other words, people with a lower general confidence in being liked by others were more influenced by negative information on a target’s SNS information when it came to predicting whether they would be treated nicely by the target in direct interactions.