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Doing More with SAS/ASSIST Software |

In this section, you perform an analysis of variance on the VENEER table to show the relationship between the brand of veneer and the amount of veneer that was worn away during testing.

Additional Information |

For additional information on performing an analysis
of variance, refer to the GLM and ANOVA procedures in the
**SAS/STAT User's Guide**.

Instructions |

- To display the Analysis of Variance window, follow this
selection path:
Tasks Data Analysis Anova Analysis of Variance *Analysis of Variance Window*

- Use the
**Table**button to select the SASUSER.VENEER table. - Use the
**Dependent**button to select**WEAR**as the dependent column.The dependent column contains the measurements to be analyzed. The Select Table Variables window displays all the numeric columns in the VENEER table except any columns selected as BY or classification columns. If you have more than one dependent column, you can generate a separate ANOVA model for each dependent column or one multivariate model for the set of dependent columns.

- Use the
**Classification**button to select**BRAND**as the classification column.The classification columns identify analysis groups. The variation in the dependent column values is analyzed within and across the classification groups to determine whether or not the classification columns are significant sources of variation. The Select Table Variables window displays all the columns in the VENEER table except for any columns selected as BY or dependent columns.

Each classification column is treated as a main effect in the model. You can modify the ANOVA model to add interactions, nested effects, covariates, and random effects by using the

**Additional options**item in the Analysis of Variance window. - Follow this selection path:
Run Submit *Analysis of Variance Output*

- Use
the scroll bars or the FORWARD command or
function key to display the next page of the analysis.
*Analysis of Variance Output (continued)*

Refer to the GLM and ANOVA procedures in the

**SAS/STAT User's Guide**for information about interpreting the statistics in this report. - Return to SAS/ASSIST software from the Output window. See
Returning to SAS/ASSIST Windows from the Output Window
for more information.

Performing a Repeated Measures ANOVA |

This example uses the data from Example 7 in "The
GLM Procedure" chapter of
**SAS/STAT User's Guide**.

Entering the Data |

- Follow this selection
path:
Tasks Data Management Create data Interactively Enter data in tabular form - In the
**Table**field, type

. If desired, select**GLMEX7****Permanent**, select a library in which to store the table, and select**OK.**. Select**Goback**. The Define a New SAS Table window appears. - Define the columns in the new table by editing
this window so that it looks like the following display.
*Define a New SAS Table Window With Columns Defined*

You might need to resize the window to see all six rows.

- Follow this selection path:
File Close **Yes**to save the changes. The FSEDIT window appears. - Enter the following data into the table. Note
that the
**hist5**column has a missing value for row 6 (**drug=Morphine, depl=N**).*Data for Repeated Measures ANOVA Example***Row (Obs)****drug****depl****hist0****hist1****hist3****hist5**1 Morphine N 0.04 0.20 0.10 0.08 2 Morphine N 0.02 0.06 0.02 0.02 3 Morphine N 0.07 1.40 0.48 0.24 4 Morphine N 0.17 0.57 0.35 0.24 5 Morphine Y 0.10 0.09 0.13 0.14 6 Morphine Y 0.12 0.11 0.10 7 Morphine Y 0.07 0.07 0.06 0.07 8 Morphine Y 0.05 0.07 0.06 0.07 9 Trimethaphan N 0.03 0.62 0.31 0.22 10 Trimethaphan N 0.03 1.05 0.73 0.60 11 Trimethaphan N 0.07 0.83 1.07 0.80 12 Trimethaphan N 0.09 3.13 2.06 1.23 13 Trimethaphan Y 0.10 0.09 0.09 0.08 14 Trimethaphan Y 0.08 0.09 0.09 0.10 15 Trimethaphan Y 0.13 0.10 0.12 0.12 16 Trimethaphan Y 0.06 0.05 0.05 0.05 - Follow this selection path to exit the
FSEDIT window:
File Close **Yes**to save the changes. - In order to minimize correlation between the mean
and the variance of the data, the logarithm of the data needs to be calculated.
Follow this selection path:
Tasks Data management Subset/Copy - If the active table is not GLMEX7, use the
**Table**button to select it from the WORK library, or, if you chose to save the table permanently, the permanent library where you saved the table. - Use the
**Output Table**button. In the Output Table or View window, specify GLM7OUT as the name of the output table. Select**Temporary**or**Permanent**, as desired, before selecting**Goback**. - Select
**Define new columns**. The Define or Modify a Column window appears. - In the
**Column**field, type

.**LHIST0** - Select
**Initialize**. The Enter Numeric Expression window appears. Select**Function**, then**Mathematical Functions**. The Select Data window appears. - Select
**LOG(n)**. The**Specify Arguments to a Function**window appears. - In the
**Value for parameter**field, type

and select**HIST0****OK**, - Select
**OK**twice. The Define New Columns window appears. - Select
**Add new column**.Repeat steps 11 through 16 to create the LHIST1, LHIST3, and LHIST5 columns, using the HIST1, HIST3, and HIST5 columns, respectively, as parameters. When finished, select

**OK**(instead of**Add New Column**) from the Define New Column to return to the Subset or Copy a Table window. - Select
**Submit**from the**Run**menu. If desired, select**OK**, then**Goback**to view the table; otherwise, select**Cancel**, then**Goback**. - You are now ready to perform the repeated measures
ANOVA. Follow this selection path:
Tasks Data Analysis Anova Analysis of Variance - If the active table is not GLM7OUT, use the
**Table**button to select the GLM7OUT table. - Use the
**Dependent**button to select the LHIST0, LHIST1, LHIST3, and LHIST5 columns. - Use the
**Classification**button to select the DRUG and DEPL columns. - Follow this selection path:
Additional options Model effects Interactions - Select
**DRUG**, then*****, then**DEPL**to construct the**DRUG*DEPL**interaction. Select**OK**, then**Goback**. - Select
**Analysis type**, then**Repeated measures**, then**Factor names and levels**. The Repeated measures Factors window appears. - In this window, you specify the repeated factor
and the number of levels associated with that factor. In the first row, type

for**TIME****Factor Name**and

for**4****Number of Levels**. Select**OK**. - Select
**Factor Values**. The Repeated measures Factor Levels window appears. - In this window, you specify the intervals for
the repeated factor. In the four active spaces under
**Level Values**, type

,**0**

,**1**

, and**3**

. Select**5****OK**. - Select
**Factor Transformations**. The Repeated Measures Transformations window appears. In this window, you specify a single-degree-of-freedom contrast. For descriptions of each transformation, select**Help**. - Select
**Polynomial**, then**OK**. - Select
**Options**. The Repeated Measures Options window appears. - Select
**Test within-subject effects**to produce an analysis-of-variance table for each contrast defined by the within-subject factors. Select**OK**. - Select
**Goback**three times to return to the Analysis of Variance window. - Select
**Submit**from the**Run**menu. The results of the analysis appear in the Output window. - If desired, compare these results to those in
Example 7 in "The GLM Procedure" chapter of
**SAS/STAT User's Guide**.

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