This bubble chart visualizes the relationship between researchers’ citation counts, ages, and paper publication numbers, with bubble size encoding publication count and color distinguishing individual researchers. The chart uses D3.js v7 to load CSV data, render SVG circles, and implement interactive tooltips that display full details on hover. Axes, labels, and a custom legend are built using D3 scales like `scaleLinear` and `scaleOrdinal`, with mouse event handlers controlling tooltip visibility and position.