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The KDE Procedure |

**PROC KDE***< options >***;**

**BWM=***numlist*-
specifies the bandwidth multipliers for the kernel density
estimate. You should specify one number for univariate smoothing and
two numbers separated by a comma for bivariate smoothing. The
default values equal 1. Larger multipliers produce a smoother
estimate, and smaller ones produce a rougher estimate.
**GRIDL=***numlist*-
specifies the lower grid limits for the kernel density estimate.
You should specify one number for univariate smoothing and
two numbers separated by a comma for bivariate smoothing. The
default values equal the minimum observed values of the variables.
**GRIDU=***numlist*-
specifies the upper grid limits for the kernel density estimate.
You should specify one number for univariate smoothing and
two numbers separated by a comma for bivariate smoothing. The
default values equal the maximum observed values of the variables.
**DATA=***SAS-data-set*-
specifies the input SAS data set to be used by PROC KDE. The
default is the most recently created data set.
**LEVELS=***numlist*-
lists percentages of data for which density contours are to
be computed. The default levels are 1, 5, 10, 50, 90, 95, 99, and
100.
**METHOD=SJPI****METHOD=SNR****METHOD=SROT****METHOD=OS**-
specifies the method used to compute the bandwidth. Available
methods are Sheather-Jones plug in (SJPI), simple normal reference
(SNR), Silverman's rule of thumb (SROT), and oversmoothed (OS).

Refer to Jones, Marron, and Sheather (1996) for a description of each of these methods. SJPI is the default for univariate smoothing, and SNR is the default and only available method for bivariate smoothing. **NGRID=***numlist***NG=***numlist*-
specifies the number of grid points associated with the variables
in the VAR statement. You should specify one number for univariate
smoothing and two numbers separated by a comma for bivariate
smoothing. The default values are 401 when there is a single VAR
variable and 60 when there are two VAR variables.
**OUT=***SAS-data-set*-
specifies the output SAS data set containing the kernel density
estimate. This output data set contains the following variables:
- variables you specify in the VAR statement, with values corresponding to grid coordinates
- density, with values equal to kernel density estimates at the associated grid point
- count, containing the number of original observations contained in the bin corresponding to a grid point

**PERCENTILES=***numlist*- lists percentiles to be computed for each VAR variable. The default
percentiles are 0.5, 1, 2.5, 5, 10, 25, 50, 75, 90, 95, 97.5, 99,
and 99.5.
**SJPIMAX=***number*- specifies the maximum grid value in determining the Sheather-Jones
plug in bandwidth. The default value is 2 times the oversmoothed
estimate.
**SJPIMIN=***number*- specifies the minimum grid value in determining the Sheather-Jones
plug in bandwidth. The default value is the maximum value divided
by 18.
**SJPINUM=***number*- specifies the number of grid values used in determining the Sheather-Jones
plug in bandwidth. The default is 21.
**SJPITOL=***number*- specifies the tolerance for termination of the bisection algorithm
used in computing the Sheather-Jones plug in bandwidth. The
default value is 1E-3.

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