Applies a moving n-term median (middle number) to an input data set. Each term in the list is replaced by a trailing median of n terms, and the first terms (the n-1 terms) are copies of the input data. @MOVMED modifies a data set for smoothing purposes.
@MOVMED (mbrName [, n [, XrangeList]])
mbrName | Any valid single member name or member combination, or a function that returns a single member or member combination. |
n | Optional. A positive integer value that represents the number of values that are used to calculate the moving median. The default is 3. |
XrangeList | Optional. A valid member name, a comma-delimited list of member names, cross dimension members, or a member set function or range function (including @XRANGE) that returns a list of members from the same dimension. If XrangeList is not specified, Analytic Services uses the level 0 members from the dimension tagged as time. |
#MISSING
values. For example, if one value out of four is
#MISSING
, @MOVMED calculates the median of the remaining
three values.Trailing Median Centered Median 1 2 3 1 2 3 2 2
The following example is based on the Sample Basic database. Assume that the Measures dimension contains an additional member, Mov Med.
"Mov Med" = @MOVMED(Sales,3,Jan:Jun);
In this example, the @MOVMED function smooths sales data for the first six months of the year (Jan through Jun). The results of @MOVMED could be used with the @TREND function to forecast sales data for a holiday season (for example, October - December).
This example produces the following report:
Colas New York Actual Sales Mov Med ===== ======= Jan 678 678 Feb 645 645 Mar 675 675 Apr 712 675 May 756 712 Jun 890 756
In this example, Analytic Services uses three values at a time to calculate the moving median. The first two values (Jan,Feb) for Mov Med are the same as the first two values for Sales. The value for Mar represents the trailing median of Jan, Feb, and Mar. The value for Apr represents the trailing median of Feb, Mar, and Apr. The remaining values represent the trailing median of each group of three values.
@MOVAVG
@MOVMAX
@MOVMIN
@MOVSUM
@MOVSUMX
@TREND
©2004 Hyperion Solutions Corporation. All Rights Reserved. http://www.hyperion.com |