Full document / COSOC-W-86-002 - the National Sea Grant Library

Table 2.—Selected SAS Data Management Tools.
Data Input
Data Set Transfer - Among Different Machines
Sorting - Multlplo Sort Fields
Character String Manipulation
Appending of Two or More Data Sets
Merging of Two or Hore Data Sets
Interleaving of Two or More Data Sets
Data Set Subsettlng Based on Logical Testing
Deletion of Variables or Observations
Variable Renaming
General Data Transformations
Maoroa - For Storing Frequently Used Sections of Code
Matrix Processing
Multiple Simultaneous Pile Processing - Input and Output
PROC TABULATE calculates descriptive statistics and displays them
In tables. The tables are suitable for most reports. This procedure
con also calculate frequency counts and percentages. PROC TABULATE
allows users a great deal of flexibility in the format of their
tables. The physioal layout of the tables and the arrangement of
variables and values in the table are controlled by the user.
Estuarine Data Quality Aaauranoo Using SAS
Many analyses supporting quality assurance aotivltles can be
carried out using SAS graphical procedures. For example, PROC GPLOT
and PRX GCRART produce scatter plots (with overlaid means and standard
deviations, if desired), bar charts, line graphs, and other types of
graphical displays. These help the estuarine researcher to identify,
e.g., keypunch and other data processing errors, and discrepancies In
measurement units. In the National Estuaries Program, data ohooking Is
an Interactive prooess. SAS print-outs are returned to the data
submitter or researcher for verification. After oorrootion, tho data
are displayed a seoond time using SAS graphical procedures to double
check the correction process.
Another Important aspect of estuarine data quality assurance is
documentation. The National Estuaries Program Data Base Includes many
different types of data oolleotod under a variety of sampling
programs. Field and analytioal procedures mist bo accurately and
oonclsely oommunioated to future Data Base users. Data associated with
unusual circumstances oust be noted. Suoh procedures and notes ore
stored in the Data Base through the use of SAS variable labels plus
supplemental, accompanying variables. For example, each physical and
chemical variable con be associated with a two byte character variable
In which remark codes are stored suoh as "less than deteotion limit.*
Another variable is used to store numeric oodos representing various
analytioal procedures. Examples of SAS variable labels are shown In
Table 1.
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