{"version":"1.0","type":"rich","title":"Circles on a Map","description":"This visualization shows global population estimates for 2018 as colored circles positioned at the geographic centroid of each country on a natural Earth projection. A size legend encodes population magnitudes, while a color legend maps a categorical scale, with countries lacking data highlighted in a different shade. The code uses d3.geoPath and d3.geoCentroid for map rendering, d3.scaleSqrt for circle sizing, and d3.scaleOrdinal with a spectral scheme for colors. Population data comes from a UN CSV dataset, joined to country geometries from a TopoJSON world atlas. Users can pan and zoom via d3.zoom, with hover tooltips showing region names and formatted population counts.","provider_name":"VizHub AI Studio","provider_url":"https://vizhub.com","html":"<iframe src=\"https://vizhub.com/viz/d9f00b50877544d89f1898e7024d5955?mode=embed\" width=\"960\" height=\"500\" scrolling=\"no\" frameborder=\"0\"></iframe>","width":960,"height":500,"cache_age":3600}