This example visualizes the relationship between fuel efficiency (miles per gallon) and horsepower across automobile models, with color mapping to the country of origin and point size encoding vehicle weight, and includes tooltips displaying model names. It uses the Vega-Lite API (vl) to declaratively define the scatter plot specification, with data loaded from the UCI Machine Learning Repository’s Auto MPG dataset via d3.csv. The visualization is rendered through Vega’s and Vega-Lite’s JavaScript libraries, integrating the Vega Tooltip for interactive hover details, and applies a custom configuration for axis and label styling.