Displayed Output

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The SURVEYREG Procedure

Displayed Output

The SURVEYREG procedure produces the following output.

Data Summary

By default, PROC SURVEYREG displays the following information in the "Data Summary" table:

Number of Observations, which is the total number of observations used in the analysis, excluding observations with missing values
Sum of Weights, if you specify a WEIGHT statement
Mean of the dependent variable in the MODEL statement, or Weighted Mean if you specify a WEIGHT statement
Sum of the dependent variable in the MODEL statement, or Weighted Sum if you specify a WEIGHT statement

Design Summary

When you specify a CLUSTER statement or a STRATA statement, the procedure displays a "Design Summary" table, which provides the following sample design information.

Number of Strata, if you specify a STRATA statement
Number of Strata Collapsed, if the procedure collapses strata
Number of Clusters, if you specify a CLUSTER statement
Overall Sampling Rate used to calculate the design effect, if you specify the DEFF option in the MODEL statement

Fit Summary

By default, PROC SURVEYREG displays the following regression statistics in the "Fit Summary" table.

R-square for the regression
Root MSE, which is the square root of the mean square error
Denominator DF, which is the denominator degrees of freedom for the F tests and also the degrees of freedom for the t tests produced by the procedure

Stratum Information

When you specify the LIST option in the STRATA statement, PROC SURVEYREG displays a "Stratum Information" table, which provides the following information for each stratum.

Stratum Index, which is a sequential stratum identification number
STRATA variable(s), which lists the levels of STRATA variables for the stratum
Population Total, if you specify the TOTAL= option
Sampling Rate, if you specify the TOTAL= option or the RATE= option. If you specify the TOTAL= option, the sampling rate is based on the number of nonmissing observations in the stratum.
N Obs, which is the number of observations
number of Clusters, if you specify a CLUSTER statement
Collapsed, which has the value 'Yes' if the stratum is collapsed with another stratum before analysis

If PROC SURVEYREG collapses strata, the "Stratum Information" table also displays stratum information for the new, collapsed stratum. The new stratum has a Stratum Index of 0 and is labeled `Pooled'.

Class Level Information

If you use a CLASS statement to name classification variables, PROC SURVEYREG displays a "Class Level Information" table. This table contains the following information for each classification variable:

Class Variable, which lists each CLASS variable name
Levels, which is the number of values or levels of the classification variable
Values, which lists the values of the classification variable. The values are separated by a white space character; therefore, to avoid confusion, you should not include a white space character within a classification variable value.

X'X Matrix

If you specify the XPX option in the MODEL statement, PROC SURVEYREG displays the X'X matrix, or the X'WX matrix when there is a WEIGHT variable. This option also displays the crossproducts vector X'y or X'Wy, where y is the response vector (dependent variable).

Inverse Matrix of X'X

If you specify the INV option in the MODEL statement, PROC SURVEYREG displays the inverse or the generalized inverse of the X'X matrix. When there is a WEIGHT variable, the procedure displays the inverse or the generalized inverse of the X'WX matrix.

ANOVA for Dependent Variable

By default, PROC SURVEYREG displays an analysis of variance table for the dependent variable. This table is identical to the ANOVA table displayed by the GLM procedure.

Tests of Model Effects

By default, PROC SURVEYREG displays a "Tests of Model Effects" table, which provides Wald's F test for each effect in the model. The table contains the following information for each effect:

Effect, which is the effect name
Num DF, which is the numerator degrees of freedom for Wald's F test
F Value, which is Wald's F statistic
Pr > F, which is the significance probability corresponding to the F Value

A footnote displays the denominator degrees of freedom, which is the same for all effects.

Estimated Regression Coefficients

PROC SURVEYREG displays the "Estimated Regression Coefficients" table by default when there is no CLASS statement. Also, the procedure displays this table when you specify a CLASS statement and also specify the SOLUTIONS option in the MODEL statement. This table contains the following information for each regression parameter:

Parameter, which identifies the effect or regressor variable
Estimate, which is the estimate of the regression coefficient
Standard Error, which is the standard error of the estimate
t Value, which is the t statistic for testing H₀: Parameter = 0
Pr > | t |, which is the two-sided significance probability corresponding to the t Value

Covariance of Estimated Regression Coefficients

When you specify the COVB option in the MODEL statement, PROC SURVEYREG displays the "Covariance of Estimated Regression Coefficients" matrix.

Coefficients of Contrast

When you specify the E option in a CONTRAST statement, PROC SURVEYREG displays a "Coefficients of Contrast" table for the contrast. You can use this table to check the coefficients you specified in the CONTRAST statement. Also, this table gives a note for a nonestimable contrast.

Analysis of Contrasts

If you specify a CONTRAST statement, PROC SURVEYREG produces an "Analysis of Contrasts" table, which displays Wald's F test for the contrast. If you use more than one CONTRAST statement, the procedure displays all results in the same table. The "Analysis of Contrasts" table contains the following information for each contrast:

Contrast, which is the label of the contrast
Num DF, which is the numerator degrees of freedom for Wald's F test
F Value, which is Wald's F statistic for testing H₀: Contrast = 0
Pr > F, which is the significance probability corresponding to the F Value

Coefficients of Estimate

When you specify the E option in an ESTIMATE statement, PROC SURVEYREG displays a "Coefficients of Estimate" table for the linear function of the regression parameters in the ESTIMATE statement. You can use this table to check the coefficients you specified in the ESTIMATE statement. Also, this table gives a note for a nonestimable function.

Analysis of Estimable Functions

If you specify an ESTIMATE statement, PROC SURVEYREG checks the function for estimability. If the function is estimable, PROC SURVEYREG produces an "Analysis of Estimable Functions" table, which displays the estimate and the corresponding t test. If you use more than one ESTIMATE statement, the procedure displays all results in the same table. The table contains the following information for each estimable function:

Parameter, which is the label of the function
Estimate, which is the estimate of the estimable liner function
Standard Error, which is the standard error of the estimate
t Value, which is the t statistic for testing H₀: Estimable Function = 0
Pr > | t |, which is the two-sided significance probability corresponding to the t Value

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