Chapter 46: The STANDARD Procedure | Base SAS 9.1 Procedures Guide, Volumes 1, 2, 3 and 4

Overview: STANDARD Procedure

What Does the STANDARD Procedure Do?

The STANDARD procedure standardizes variables in a SAS data set to a given mean and standard deviation, and it creates a new SAS data set containing the standardized values.

Standardizing Data

Output 46.1 shows a simple standardization where the output data set contains standardized student exam scores. The statements that produce the output follow:

 proc standard data=score mean=75 std=5                out=stndtest;  run;  proc print data=stndtest;  run;

Output 46.1: Standardized Test Scores Using PROC STANDARD

 The SAS System                       1   Obs    Student       Test1     1    Capalleti    80.5388     2    Dubose       64.3918     3    Engles       80.9143     4    Grant        68.8980     5    Krupski      75.2816     6    Lundsford    79.7877     7    McBane       73.4041     8    Mullen       78.6612     9    Nguyen       74.9061    10    Patel        71.9020    11    Si           73.4041    12    Tanaka       77.9102

Output 46.2 shows a more complex example that uses BY- group processing. PROC STANDARD computes Z scores separately for two BY groups by standardizing life-expectancy data to a mean of 0 and a standard deviation of 1. The data are 1950 and 1993 life expectancies at birth for 16 countries . The birth rates for each country, classified as stable or rapid, form the two BY groups. The statements that produce the analysis also

print statistics for each variable to standardize
replace missing values with the given mean
calculate standardized values using a given mean and standard deviation
print the data set with the standardized values.

For an explanation of the program that produces this output, see Example 2 on page 1187.

Output 46.2: Z Scores for Each BY Group Using PROC STANDARD

 Life Expectancies by Birth Rate               2  -------------------- PopulationRate=Stable --------------------                      The STANDARD Procedure                                     Standard       Name              Mean       Deviation              N       Label       Life50       67.400000        1.854724              5       1950 life expectancy       Life93       74.500000        4.888763              6       1993 life expectancy  --------------------- PopulationRate=Rapid --------------------                                    Standard       Name              Mean       Deviation              N       Label       Life50       42.000000        5.033223              8       1950 life expectancy       Life93       59.100000        8.225300             10       1993 life expectancy

 Standardized Life Expectancies at Birth               3                by a Countrys Birth Rate  Population     Rate        Country           Life50     Life93    Stable       France           -0.21567    0.51138    Stable       Germany           0.32350    0.10228    Stable       Japan            -1.83316    0.92048    Stable       Russia            0.00000   -1.94323    Stable       United Kingdom    0.86266    0.30683    Stable       United States     0.86266    0.10228    Rapid        Bangladesh        0.00000   -0.74161    Rapid        Brazil            1.78812    0.96045    Rapid        China            -0.19868    1.32518    Rapid        Egypt             0.00000    0.10942    Rapid        Ethiopia         -1.78812   -1.59265    Rapid        India            -0.59604   -0.01216    Rapid        Indonesia        -0.79472   -0.01216    Rapid        Mozambique        0.00000   -1.47107    Rapid        Philippines       1.19208    0.59572    Rapid        Turkey            0.39736    0.83888