assigns the calculated result to the secondary (right)
vertical axis.
Required Argument
response-variable
specifies the variable
for the x axis. The variable must be numeric.
Optional Arguments
FREQ= numeric-variable
specifies how many times observations are repeated
for computational purposes.Each observation is
repeated n times for computational
purposes, where n is the value
of the numeric variable. If n is
not an integer, then it is truncated to an integer. If n is
less than 1 or missing, then it is excluded from the analysis.
LEGENDLABEL= "text-string"
specifies a label that identifies the density plot
in the legend. By default, the label
identifies the type of density curve. If you specify TYPE=NORMAL,
then the default label is “Normal.“ If you specify TYPE=KERNEL,
then the default label is “Kernel.“
Note:User-specified parameters from the TYPE= option are included
in the label by default.
LINEATTRS= style-element<(options)> |
(options)
specifies the appearance of the density line.You can specify the
appearance by using a style element or by using suboptions. If you
specify a style element, you can also specify suboptions to override
specific appearance attributes.
options can
be one or more of the following:
COLOR= color
specifies
the color of the line. You
can specify colors using the same color schemes that are supported
by SAS/GRAPH software. For more information, see Color-Naming Schemes in SAS/GRAPH: Reference.
Default:The default color is specified by the ContrastColor
attribute of the GraphFit style element in the current style.
PATTERN= line-pattern
specifies
the line pattern for the line. You can reference SAS patterns by number or by name. For a list of line patterns,
see Line Patterns.
Default:The default line pattern is specified by the LineStyle
attribute of the GraphFit style element in the current style.
THICKNESS= n<units>
specifies
the thickness of the line. You can also specify the unit of measure.
The default unit is pixels. For
a list of measurement units that are supported, see Units of Measurement.
Default:The default line thickness is specified by the LineThickness
attribute of the GraphFit style element in the current style.
NAME= “text-string”
specifies a name for the plot.You can use the name
to refer to this plot in other statements.
Note:The name is case-sensitive. When you refer to the specified
name in other statements, you must use the same exact capitalization.
SCALE= scaling-type
specifies the scaling that is used for the response
axis.Specify one of the
following values:
COUNT
the axis displays the
frequency count.
DENSITY
the axis displays the
density estimate values.
PERCENT
the axis displays values
as a percentage of the total.
PROPORTION
the axis displays values
in proportion to the total.
Default:DENSITY
Note:The PROPORTION scale can be used only when you combine
a density plot and a histogram together.
TRANSPARENCY= numeric-value
specifies the degree of transparency for the density
curve.Specify a value from
0.0 (completely opaque) to 1.0 (completely transparent).
Default:0.0
TYPE = NORMAL < (normal-opts)>|
KERNEL < (kernel-opts)>
specifies the type of distribution curve that is
used for the density plot.Specify one of the
following keywords:
NORMAL < (normal-opts)>
specifies a normal
density estimate, with a mean and a standard deviation.
normal-opts can
be one or more of the following values:
MU= numeric-value
specifies the mean
value that is used in the density function equation. By default, the
mean value is calculated from the data.
SIGMA= numeric-value
specifies the standard
deviation value that is used in the density function equation. The
value that you specify for the SIGMA= suboption must be a positive
number. By default, the standard deviation value is calculated from
the data.
KERNEL < (kernel-opts)>
specifies a nonparametric
kernel density estimate.
kernel-opts can
be:
C= numeric-value
specifies the standardized
bandwidth for a number that is greater than 0 and less than or equal
to 100.
The value that you
specify for the C= suboption affects the value of λ as shown
in the following equation:
In this equation c is
the standardized bandwidth, Q is
the interquartile range, and n is
the sample size.
WEIGHT= NORMAL | QUADRATIC | TRIANGULAR
specifies the weight
function. You can specify either normal, quadratic, or triangular
weight function.
Default:NORMAL
Default:NORMAL
X2AXIS
assigns the X variable to the secondary (top) horizontal
axis.
Y2AXIS
assigns the calculated result to the secondary (right)
vertical axis.
Details
Normal Density Function
When the type of the
density curve is NORMAL, the fitted density function equation is as
follows.
In the equation, μ
is the mean, and σ is the standard deviation. You can specify
μ by using the MU= suboption and σ by using the SIGMA=
suboption.
Kernel Density Function
When the TYPE of the
density curve is KERNEL, the general form of the kernel density estimator
is as follows.
In the equation, is the weight function, λ is the bandwidth, n is
the sample size, and is the ith
observation. You can use the C= suboption to specify the bandwidth
and the WEIGHT= suboption to specify the weight function .
Kernel Density Weight Functions
The formulas for the
weight functions are as follows.