Normal probability plot
h = normplot(X)
h = normplot(X) displays
a normal probability plot of the data in
X, normplot displays a line for each column
h is a handle to the plotted
The plot has the sample data displayed with the plot symbol
Superimposed on the plot is a line joining the first and third quartiles
of each column of
X (a robust linear fit of the
sample order statistics.) This line is extrapolated out to the ends
of the sample to help evaluate the linearity of the data.
The purpose of a normal probability plot is to graphically assess
whether the data in
X could come from a normal
distribution. If the data are normal the plot will be linear. Other
distribution types will introduce curvature in the plot.
midpoint probability plotting positions. Use
the data included censored observations.
Generate random sample data from a normal distribution with
mu = 10 and
sigma = 1.
rng default; % For reproducibility x = normrnd(10,1,25,1);
Create a normal probability plot of the sample data.
The plot indicates that the data follows a normal distribution.