Download The whiskers extend to a maximum of 1.5(IQR) beyond the box

2. DESCRIPTIVE STATISTICS
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The whiskers extend to a maximum of 1.5(IQR) beyond the box. Values
1.5(IQR) to 3(IQR) are labeled with and are termed outliers. Values beyond
3(IQR) are labeled with ⇤ and are termed extremes.
Kurtosis – a measure of the degree to which a distribution is “peaked” or flat
in comparison to a normal distribution whose graph is characterized by a bellshaped distribution. The names of 3 basic types of curves are given below.
n
X
n
(xi
Kurtosis = ✓ ni=1
X
(xi
i=1
Summary
x)4
x)2
◆2
3=
n
X
n
(xi
x)4
i=1
(n
1)2s4
3.
In describing the center and dispersion of a data distribution, one usually either
provides the mean and standard deviation or the five-number summary, the
choice depending on the shape of the distribution – mean and standard deviation
for symmetric data and the five-number summary for non-symmetric data.
Maple. See centdist.mw and centdist.pdf.