Table 3. Classification of previous studies according to their unit of analysis.
| Authors | User profile | Content | |
|---|---|---|---|
| Textual | Behavioral | ||
| Li et al. (2014) | √ | – | – |
| Lin et al. (2014) | √ | – | – |
| Ramalingam & Chinnaiah (2018) | √ | – | – |
| Banerjee et al. (2015) | – | √ | – |
| Cardoso, Silva & Almeida (2018) | – | √ | – |
| Chang et al. (2015) | – | √ | – |
| Chen, Guo & Deng (2014) | – | √ | – |
| Deng & Chen (2014) | – | √ | – |
| Elmurngi & Gherbi (2017) | – | √ | – |
| Lappas, Sabnis & Valkanas (2016a) and Lappas, Sabnis & Valkanas (2016b) | – | √ | – |
| Munzel (2016) | – | √ | √ |
| Banerjee & Chua (2014) | – | – | √ |
| Li, Feng & Zhang (2016) | – | – | √ |
| Li et al. (2018) | – | – | √ |
| Luca & Zervas (2016) | – | – | √ |
| Zhang et al. (2016) | – | – | √ |
| Hunt (2015) | – | – | – |