## 2 Exploratory Data Analysis
### Information Analisis  
To interpret the results correctly, it is important to bear in mind that actual harassment events and the number of reports are not strongly correlated. There are numerous social and cultural factors, such as awareness of the Hollaback! platform, which may favor more or less reporting depending on the conditions. Some of the factors thought to be affected are geographic location, time of occurrence, language of reporting or type of harassment. First, we located the origin of the complaints. Thanks to the free tool called Carto [18], different data layers can be represented on a dynamic map. In this case, a representation of the reports was made on a world map using the latitude and longitude provided. In this way, it was possible to observe the general distribution of the reports, which reflects, to a large extent, the global scope of the Hollaback! movement. In this picture, it can be seen that the complaints are mainly concentrated in Europe and the United States. In these places, the Hollaback! movement is strongest, and this is due to several factors. One of the most important is because they are the first places where the platform was launched and therefore the origin of the movement, namely, in New York. This image (Figure 2), also reflects the areas of the world where the movement has not yet reached, such as Africa, or is just beginning to gain momentum, such as India, Southeast Asia and South America. Figure 2: Worldwide distribution of complaints. Another interesting datum is the distribution of the number of complaints over the years, showing how the success and scope of Hollaback! has varied since its creation. It can be observed that since it started in 2005, the number of users grew until 2014 where it had its highest point; since then, the number of complaints has been decreasing over the years. One might think that the drop is due to a decrease in the number of harassment situations; however, it is unlikely that the decrease is so large, especially when compared to general statistics. Therefore, it is more likely that the decrease is caused by the emergence of new similar platforms [19], such as StoPit Solutions [20], the #notme app [21], Spot [22] and some other similar apps that have caused this decrement in the distribution of users, as Figure 3 shows. Subsequently, the distribution of complaints was studied according to four time intervals: early morning (1 a.m. to 6 a.m.), morning (7 a.m. to 12 a.m.), afternoon (1 p.m. to 6 p.m.) and evening (7 p.m. to 12 p.m.). The objective was to see in which intervals it is more frequent to suffer a harassment experience and also to see how these experiences are distributed in a city. In this case, the city of Madrid was chosen in order to better understand the results. We chose Madrid because there were many complaints collected in this city during a limited amount of time. Additionally, the city is very well divided into mostly residential neighborhoods, and other regions with nightlife activity where more harassment events are expected. Despite there being other cities, we chose Madrid as an example used to show the information that could be obtained from the database and that would allow for a better understanding of the dynamics of the city. In Figure 4, it is clear that the lowest number of incidents occurred in the early morning, but that they are more concentrated in the center. In the rest of the time intervals, the concentration of complaints continues to be in the most central sector; however, in the mornings, it tends to be displaced to the north, and in the afternoons, to the southeast. The majority concentration in the center is due to Hollaback! being better known among foreigners who move mainly in that area. This can be verified by looking at the language of the descriptions, with English almost always in the center and Spanish on the outskirts. Therefore, it cannot be deduced that there is more harassment in one area or another, only that it is more reported.