The test statistic in an ANOVA test follows the F-distribution. The F-distribution graph is not symmetric, and its shape depends on two parameters dfn and dfd.

dfn = degrees of freedom while calculating the estimate of the variance of the numerator and
dfd = degrees of freedom while calculating the estimate of the variance of the denominator

In a one-way ANOVA test,

dfn = (total number of groups – 1)
And dfd = (total number of observations – total number of groups)

We can use the following Python code to generate the F-distribution graph for dfn = 10 and dfd = 50.

from scipy.stats import f
import numpy
from matplotlib import pyplot
 
X = numpy.linspace(0, 5, 200)
dfn = 10
dfd = 50
Y = f.pdf(X, dfn, dfd)
pyplot.plot(X, Y)
pyplot.savefig("f-dist.png")
pyplot.close()

Here, we are using the numpy.linspace() function to generate 200 equally spaced points on the x-axis within the range 0 to 5. After that, we are using the f.pdf() function from the scipy.stats module to generate the corresponding points on the y-axis.

The output graph of the above program will look like the following: …