There are problems that still exist in online learning including limited-reach networks, inadequate facilities and infrastructure, and others. This study discussed the analysis of sentiment which used the Na ve Bayes Classifier (NBC) method with XGBoost feature selection as a performance improvement that took data from news portals. The results of this study showed that graph data on the application of online learning forms in Indonesia had a "Negative" opinion. Performance testing of the NBC method based on XGBoost feature selection was conducted four times. The first experiment resulted in an accuracy value of 60.18% with 50/50 split data. The next experiment had an accuracy value of 56.92% with 70/30 split data. After that, the third experiment resulted in an accuracy value of 65.90% with 80/20 split data. The result of the last experiment was an accuracy value of 63.63% with 90/10 split data. After using XGBoost feature selection, it produced an accuracy of 60.18%, 67.69%, 70.45%, and 77.27%. The study also produced the highest average score at 10-Fold Cross-Validation in the second trial with a score of 65.62%.

Futsal is a soccer game played indoors, this game itself is played by two teams, each team consisting of five people. At this time futsal is very much in demand from various groups ranging from children to adults, so there are many futsal field rental places, especially in the city of Pekanbaru. However, the problem that occurs is that it is still difficult for tenants to find out where there is a futsal field and the nearest futsal field from where the tenant is located, including price information and field facilities. Therefore, we need a system that can make it easier for tenants to find out where there is a futsal field and the nearest futsal field from the tenant's location. This system is made based on Android so that it can make it easier for users to use this system. The method used in making this system is the Haversine method. The results obtained are a marketplace system that can make it easier for users to find out where there is a futsal field, find the nearest field and it is also easy to find out all information related to the field and can make it easier to rent a futsal field through the marketplace system.