Binned Scatterplot
This example shows how to make a binned scatterplot.
import altair as alt
from vega_datasets import data
source = data.movies.url
alt.Chart(source).mark_circle().encode(
alt.X('IMDB_Rating:Q', bin=True),
alt.Y('Rotten_Tomatoes_Rating:Q', bin=True),
size='count()'
)