Generate Kernel Density Estimate plot using Gaussian kernels.
In statistics, kernel density estimation (KDE) is a non-parametric
way to estimate the probability density function (PDF) of a random
variable. This function uses Gaussian kernels and includes automatic
bandwidth determination.
Parameters:
bw_methodstr, scalar or callable, optional
The method used to calculate the estimator bandwidth. This can be
‘scott’, ‘silverman’, a scalar constant or a callable.
If None (default), ‘scott’ is used.
See scipy.stats.gaussian_kde for more information.
indNumPy array or int, optional
Evaluation points for the estimated PDF. If None (default),
1000 equally spaced points are used. If ind is a NumPy array, the
KDE is evaluated at the points passed. If ind is an integer,
ind number of equally spaced points are used.
weightsNumPy array, optional
Weights of datapoints. This must be the same shape as datapoints.
If None (default), the samples are assumed to be equally weighted.
**kwargs
Additional keyword arguments are documented in
DataFrame.plot().
Representation of a kernel-density estimate using Gaussian kernels. This is the function used internally to estimate the PDF.
Examples
Given a Series of points randomly sampled from an unknown
distribution, estimate its PDF using KDE with automatic
bandwidth determination and plot the results, evaluating them at
1000 equally spaced points (default):
A scalar bandwidth can be specified. Using a small bandwidth value can
lead to over-fitting, while using a large bandwidth value may result
in under-fitting:
>>> ax=s.plot.kde(bw_method=0.3)
../../_images/pandas-DataFrame-plot-kde-2.png
>>> ax=s.plot.kde(bw_method=3)
../../_images/pandas-DataFrame-plot-kde-3.png
Finally, the ind parameter determines the evaluation points for the
plot of the estimated PDF:
A scalar bandwidth can be specified. Using a small bandwidth value can
lead to over-fitting, while using a large bandwidth value may result
in under-fitting:
>>> ax=df.plot.kde(bw_method=0.3)
../../_images/pandas-DataFrame-plot-kde-6.png
>>> ax=df.plot.kde(bw_method=3)
../../_images/pandas-DataFrame-plot-kde-7.png
Finally, the ind parameter determines the evaluation points for the
plot of the estimated PDF: