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The ANOVA Procedure |

**PROC ANOVA***< options >***;**

The PROC ANOVA statement starts the ANOVA procedure.

You can specify the following options in the PROC ANOVA statement:

**DATA=***SAS-data-set*-
names the SAS data set used by the ANOVA procedure.
By default, PROC ANOVA uses the most recently created SAS data set.
**MANOVA**-
requests the multivariate mode of eliminating
observations with missing values.
If any of the dependent variables have missing values,
the procedure eliminates that observation from the analysis.
The MANOVA option is useful if you use PROC ANOVA in interactive
mode and plan to perform a multivariate analysis.
**MULTIPASS**-
requests that PROC ANOVA reread the input data set,
when necessary, instead of writing the values of
dependent variables to a utility file.
This option decreases disk space usage at the expense of
increased execution times and is useful only in rare situations
where disk space is at an absolute premium.
**NAMELEN=***n*-
specifies the length of effect names to be
*n*characters long, where*n*is a value between 20 and 200 characters. The default length is 20 characters. **NOPRINT**-
suppresses the normal display of results.
The NOPRINT option is useful when you want to create
only the output data set with the procedure.
Note that this option
temporarily disables the Output Delivery System

(ODS); see Chapter 15, "Using the Output Delivery System," for more information. **ORDER=DATA | FORMATTED | FREQ | INTERNAL**-
specifies the sorting order for the levels of the
classification variables (specified in the CLASS statement).
This ordering determines which parameters in the model
correspond to each level in the data.
Note that the ORDER= option applies to the levels for all
classification variables.
The exception is ORDER=FORMATTED (the default) for numeric variables
for which you have supplied no explicit format
(that is, for which there is no corresponding FORMAT statement in the
current PROC ANOVA run or in the DATA step that created the data set).
In this case, the
levels are ordered by their internal (numeric) value. Note that this
represents a change from previous releases for how class levels are
ordered. In releases previous to Version 8, numeric class levels with
no explicit format were ordered by their BEST12. formatted values, and
in order to revert to the previous ordering you can specify this
format explicitly for the affected classification variables. The
change was implemented because the former default behavior for
ORDER=FORMATTED often resulted in levels not being ordered
numerically and usually required the user to intervene with an
explicit format or ORDER=INTERNAL to get the more natural ordering.
The following table shows how PROC ANOVA interprets values
of the ORDER= option.
**Value of ORDER=****Levels Sorted By**DATA order of appearance in the input data set FORMATTED external formatted value, except for numeric variables with no explicit format, which are sorted by their unformatted (internal) value FREQ descending frequency count; levels with the most observations come first in the order INTERNAL unformatted value **OUTSTAT=***SAS-data-set*-
names an output data set that contains sums of
squares, degrees of freedom,
*F*statistics, and probability levels for each effect in the model. If you use the CANONICAL option in the MANOVA statement and do not use an M= specification in the MANOVA statement, the data set also contains results of the canonical analysis. See the "Output Data Set" section for more information.

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