PROPORTIONAL SYMBOL
The map shows up the spatial distribution of rodent incidents in Buffalo. The transparent polygons with black boundaries represent different council districts and their centroids are marked by the red dots. The larger size of the dot means that there is more rodent incident happening here. To obtain the map, I used Mapbox to edit my attribute table, design the map style, prove the layout of the map, and used QGIS to process raw data and get centroid points in each area In the end, I used JSFiddle to edit my HTML page and updated my map in the webpage.
When I set up the radius of the centroid dot, I set thresholds for different rodent incident:5 px to represent the minimum rodent incident number(1566) and 10px to represent the maximum rodent incident number(2344). Mapbox, QGIS, JSFiddle, and Bracket are important software in establishing the online map. We use QGIS to modify the data attributes, calculate data results and update them to Mapbox and transferred them into tileset which is a collection of raster and vector data broken up into a uniform grid of square tiles, making the map visible on mobile devices and web browsers. In addition, we use JSFiddle to set up the layout of Mapbox, such as style, center, and zoom in HTML files. Last but not least, we used Bracket to edit all the HTML files and CSS files and combined them together to establish a complete web page.
From the map, it's easy for us to find out that the red dots in the south region are larger than the north area on average, which means most rodent incidents have happened in the south area. The influence factors might be related to the natural environment, urban development, citizen population and etc.