## 6 Conclusions
### Limitations and Future Research  
This paper has many limitations. The sample represented only urban hotels in Thessaloniki. The hotel features defined in online reviews clearly reflect location-related features of the hotels. Consumer experience in these hotels is not similar to the experience in hotels in less populated, rural areas, or Greek islands. Nevertheless, possible restrictions on the generalizability of the results do not decrease the data's internal validity. They, therefore, do not prevent the goal of presenting the significance of big data in the tourism sector. Furthermore, only one source of data was used in this paper. While booking.com includes adequate hotel guest reviews, the outcomes of this paper may be limited and should be explained carefully. Future researchers may consider applying different methods to multiple data sources to create a complete understanding of customer satisfaction using big data. Further research can be implemented to explore the factors of consumer satisfaction and dissatisfaction using various data sources, such as consumer comments cards, surveys, interviews with consumers, hotel booking websites, different social media websites, and so on. These sources may provide more details about consumer perception, such as consumer familiarity and consumer loyalty; consumer willingness to pay can also be analyzed through UGC.  
Future researchers can compare consumer satisfaction and dissatisfaction factors regarding different types of hotels that provide various services. By analyzing hotel types and the significance in customer ranking of consumer satisfaction and dissatisfaction regarding different types of hotels, future researchers will be able to examine the benefits and disadvantages of each type of hotel's performance based on their consumers' attitudes. Hotel managers can formulate market segmentation strategies to define various consumers' needs with various travel purposes and demographics. Therefore, service quality can be increased. Hotel managers may implement the market segmentation process to fulfill the specific demands of consumers for each hotel type. Thus, further research is necessary in order to examine whether demographics such as consumers' gender, age, or travel purpose (leisure vs. business) can impact on guest satisfaction and dissatisfaction.  
Future researchers can examine if positive reviews significantly influence hotels' online transaction volumes and if negative reviews impact on staffs' personal and professional outcomes as well as on hotels' outcomes. These dimensions negatively affect online hotel bookings. Therefore, defining the dimensions of hotel guest satisfaction and dissatisfaction using UGC and offering specific improvement actions are significant actions for hoteliers to take in order to improve their reputation, relationships with customers, and hotel performance.  
Conceptualization, F.K. and M.K.; methodology, P.K.; formal analysis, E.G.; investigation, F.K. and P.K.; data curation, F.K.; writing--original draft preparation, P.K. and M.K.; writing--review and editing, F.K., P.K., E.G. and M.K.; supervision, F.K. and E.G. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.