This choropleth map displays global economic classifications by country, with a linked color legend that filters the map when a legend item is clicked. Hovering over a legend entry dims all other legend items and corresponding map regions to 0.1 opacity, while clicking toggles the filter on or off. The visualization uses d3.geoNaturalEarth1 and d3.geoPath to project world boundaries from TopoJSON data, with d3.scaleOrdinal and schemeSpectral encoding the categorical values. D3 zoom enables panning and zooming, and the legend’s interactive filtering is handled via click events on SVG groups.