*1.6. Research Involving Questionnaires*

Before the explosion of online sentiment mining, researchers solely used qualitative data collection methods in the form of surveys and particularly questionnaires [52]. Online questionnaires have many advantages, including increased collection of data, decreased cost and time to collect data and readily exportable formats for analytical simplicity [53,54]. To establish trends, attitudes and patterns, questionnaires are usually incorporated into mixed-method research and often yield information that computer-based programs may not identify. For example, questionnaires can extract demographic information and include questions exploring the reasoning behind opinions [54].
