Altair — Scatter Plot

Bubble scatter where size encodes component popularity, colour groups by category, and every point carries a four-field tooltip on hover.

Notes

• encoding.size with a custom scale.range gives a clear visual gradient between smallest and largest bubble.
• Layered circle + text marks share the same dataset and x/y encodings — that’s how labels track their points without duplicating data.
• Tooltips are declarative: name the fields, give them friendlier titles, and Vega-Lite renders the panel on hover with no custom DOM.