{"version":"1.0","type":"rich","title":"EdX Viewership 2013: Adding Dropdowns","description":"This example maps the geographic distribution of video views in HarvardX/MITx online courses from 2013. Circles sized by view count are projected onto a world map using `d3.geoMercator` and `d3.geoPath`, with graticules and country interiors drawn from World Atlas TopoJSON. The visualization includes dropdown menus to filter data by course and institution, though filtering logic and tooltips are not yet implemented. Data comes from a CSV file loaded via `d3.csv`, and the React component structure uses hooks like `useState` and `useEffect` alongside d3 scales for sizing.","provider_name":"VizHub AI Studio","provider_url":"https://vizhub.com","html":"<iframe src=\"https://vizhub.com/viz/48c4dced41d0435da3efe7d0f3f0337f?mode=embed\" width=\"960\" height=\"500\" scrolling=\"no\" frameborder=\"0\"></iframe>","width":960,"height":500,"cache_age":3600}