3.2. Measurement
Five constructs were measured in the current study: purchase decision, product usefulness evaluation, source credibility,
argument quality, and tie strength. All the items of scale used the five-point Likert scales anchored between ‘‘strongly disagree’’
and ‘‘strongly agree’’.
Purchase decision pertains to the extent of a consumer has a clear answer of the probability of purchasing a special product
by communicating with other consumers. Measurement for purchase decision was adapted from the scale of Dodds
et al. (1991). This portion included three items.
Product usefulness evaluation refers to the extent of a consumer has a clear answer of whether purchasing a special product
would be beneficial to his/her life by communicating with other consumers. Measurement for product usefulness evaluation
was adapted from the scale of Moldovan et al. (2011). This portion included four items