This bubble chart visualizes Spotify’s new collection, plotting each artist as a circle based on their average valence (x-axis) and average popularity (y-axis), with circle size representing the number of tracks. Hovering over a circle reveals a tooltip with the artist’s name and track count. The chart uses d3.scaleLinear for axes and bubble size, d3.scaleOrdinal with d3.schemeSet2 for color, and SVG circles with CSS hover strokes. Data is aggregated from a CSV file via d3.csv, and the visualization is rendered with d3.v4 and an animated tooltip.