plotnine.geom_smooth

geom_smooth(mapping=None, data=None, **kwargs)

A smoothed conditional mean

{usage}

Parameters

legend_fill_ratio : float = 0.5

How much (vertically) of the legend box should be filled by the color that indicates the confidence intervals. Should be in the range [0, 1].

See Also

stat_smooth

The default stat for this geom.

Examples


from plotnine import ggplot, aes, geom_point, geom_smooth, labs, theme_matplotlib, theme_set
from plotnine.data import mpg

theme_set(theme_matplotlib())

Smoothed conditional means

Aids the eye in seeing patterns in the presence of overplotting.

mpg.head()
manufacturer model displ year cyl trans drv cty hwy fl class
0 audi a4 1.8 1999 4 auto(l5) f 18 29 p compact
1 audi a4 1.8 1999 4 manual(m5) f 21 29 p compact
2 audi a4 2.0 2008 4 manual(m6) f 20 31 p compact
3 audi a4 2.0 2008 4 auto(av) f 21 30 p compact
4 audi a4 2.8 1999 6 auto(l5) f 16 26 p compact 
(
    ggplot(mpg, aes(x="displ", y="hwy"))
    + geom_point()
    + geom_smooth()
    + labs(x="displacement", y="horsepower")
)

Use span to control the “wiggliness” of the default loess smoother. The span is the fraction of points used to fit each local regression: small numbers make a wigglier curve, larger numbers make a smoother curve.

(
    ggplot(mpg, aes(x="displ", y="hwy"))
    + geom_point()
    + geom_smooth(span=0.3)
    + labs(x="displacement", y="horsepower")
)

You can remove confidence interval around smooth with se=False:

(
    ggplot(mpg, aes(x="displ", y="hwy"))
    + geom_point()
    + geom_smooth(span=0.3, se=False)
    + labs(x="displacement", y="horsepower")
)

Instead of a loess smooth, you can use any other modelling function:

(
    ggplot(mpg, aes(x="displ", y="hwy"))
    + geom_point()
    + geom_smooth(method="lm")
    + labs(x="displacement", y="horsepower")
)

Points & Linear Models

# Gallery, points

(
    ggplot(mpg, aes(x="displ", y="hwy", color="factor(drv)"))
    + geom_point()
    + geom_smooth(method="lm")
    + labs(x="displacement", y="horsepower")
)

Source: Smoothed conditional means