SAS System SAS contains an excellent graphics package for producing graphics and visuals to enhance the display and reporting of statistical information. The focus of this study is to examine the graphics uses of the SAS system and to provide a description for each use of graphics with the SAS system and then to compare the SAS system with other graphics packages available in today's market. Toward this end, this work will conduct a review of literature in this area of study.

(1) What are the various types of graphics that can be performed using the SAS system?

(2) What are the applications of SAS graphics?

(3) How does SAS graphics differ from other graphics packages?

The work of Phil Spector reports that the SAS system was developed in the early 1970s decade at North Caroline State University and was intended originally for use by management and analysis of agricultural field experiments. (paraphrased) SAS is reported as the most widely used statistical software. SAS stands for 'Statistical Analysis System'. SAS products are reported by Spector ( ) to include those stated as follows:

(1) Base SAS -- data management and basic procedures;

(2) SAS/STAT -- statistical analysis;

(3) SAS/GRAPH -- presentation quality graphics;

(4) SAS/OR -- operations research;

(5) SAS/ETS -- Econometrics and Time Series Analysis;

(6) SAS/IML -- Interaction matrix language;

(7) SAS/AF -- applications facility (menus and interfaces); and (8) SAS/QC -- quality control. (Spector, nd, p.2)

Spector reports that there are other "specialized products for spreadsheets, access to databases, connectivity between different machines running SAS" as well as others. (nd, p.2) Most SAS programs have two primary components: (1) the data step(s); and (2) the procedure step(s). (Spector, nd, p.3) The data step "reads data from external sources, manipulates, and combines it with other data set and print reports. The data step is used to prepare the data for use by one of the procedures." (Spector, nd, p.6)

SAS is reported as being "very lenient about the format of its input -- statements can be broken up across lines, multiple statements can appear on a single line and blank spaces and lines can be added to make the program more readable." (Spector, nd, p.6) The procedure steps are such that "perform analysis on the data, and produce outputs" often in large amounts. (Spector, nd, p.6) The most effective learning strategy for SAS is concentration on the "details of the data step and learn the details of each procedure" as there is a need for them. (Spector, nd, p.6)

It is reported by UCLA Academic Technology Services that SAS graphics include:

(1) Graph-N-Go

(2) SAS/INSIGHT;

(3) SAS/ANALYST; and (4) SAS/PROCS. (UCLA Academic Technology Services, 2012, p.1)

I. Graph-N-Go

Graph-N-Go is reported as being primarily for reporting and to have the strong point of "flexibility to save a plot in various formats, including graphic format and html format. Its weak point is that it only supports a few graph types." (UCLA Academic Technology Services, 2012, p.1) The Graph-N-Go reporting creates a graphic that appears in the following illustration labeled Figure 1.

Figure 1 - Graph-N-Go

Source: UCLA Academic Technology Services (2012)

II. SAS/Insight

SAS/Insight is reported as a package that can be used in the exploration of variable and relationships among variables. The strong point is that this package offers a great amount of detailed information concerning variables including "such as univariate statistics." (UCLA Academic Technology Services, 2012, p.1) In addition, all of the graph files can be saved to .gif files or other graphic files. The limitation is that it is difficult to modify the color of style of the graphs. However, its strong feature is its interaction feature, which enables exploration of data "both graphically and analytically." (UCLA Academic Technology Services, 2012, p.1) The following illustration shows the SAS/Insight graphics example:

Figure 2 SAS/Insight Graphic (Rotating Plot, YZX)

Source: UCLA Academic Technology Services (2012)

III. SAS/Analyst

SAS Analyst attempt to explore and report and is described as an excellent place to begin since many types of graphs can be creating and the SAS code for creating the plots is created as well and the settings can be changed and code modified if it is needed. This is true for graphics and statistical analysis. The following illustration shows an SAS/Analyst graph.

Figure 3 SAS/Analyst Graph

Source: UCLA Academic Technology Services (2012)

The options used to generate this...

SAS/Procs: Univariate, Boxplot, Gplot, Gchart, G3d
The SAS/Procs: Univariate, Boxplot, Gplot, Gchart, G3d is reported useful in the creation of more customized types of graphs. Types of graphs created with SAS/Procs include those in the following figures:

Figure 4 -- Histogram

Source: UCLA Academic Technology Services (2012 )

Figure 5 - The same histogram improved due to the ability to modify settings and make changes.

Source: UCLA Academic Technology Services (2012)

The difference between the SAS System and other graphics packages is reported in the work of Schabenberger to include that while the "core of the SAS System contains several procedures for simple line printer graphics, such as PROC PLOT and PROC Chart, the output of these procedures are not publication quality." (UCLA Academic Technology Services, 2012, p.1) The SAS/GRAPH module contains procedures for creating high quality graphics. While it is easy to use procedures such as GPLOT, GCHART, G3D, etc. And produce some nice looking graph on screen, it is yet another story to format these graphics for a specific output device, so that they can be printed, copied to a word processor, exported as GIFs, etc." (UCLA Academic Technology Services, 2012, p.1) The study of the SAS/GRAPH includes a manual two volumes in length, which is required to learn the "ins and outs of this process." (UCLA Academic Technology Services, 2012, p.1)

V. Comparison to Other Graphics Packages

There are other graphics packages including SigmaPlot, PlotIt, Axum and others "where graphs are produced from spreadsheet like data. Annotations are placed on the graph in an interactive fashion. The graph type is chosen through a graphical user interface, and so forth. In SAS/GRAPH graphics are produced usually by programming statements in the PROGRAM EDITOR and executing them (there are other ways to create graphs in SAS, e.g. SAS/INSIGHT and SAS/SPECTRAVIEW). The definition of axes, annotations, notes on the graph, the data to be used, the size and type of symbols and lines are all part of the program." (UCLA Academic Technology Services, 2012, p.1) Novice users find this challenging however, it is a powerful feature enabling the user to gain "complete control over the appearance of a graph, it results in a storable program that can be executed at a later time for a different data set, producing essentially the same graph with new data. One can create multiple graphs from a data set with annotations that are placed identically, can change their values depending on the contents of a data set without user intervention. Rather than storing a huge graphics file" the individual can choose to save a small SAS program that creates the desired graphic upon execution. (UCLA Academic Technology Services, 2012, p.1)

Goptions are reported to be the graphics options that give definition to the output device in terms of the formatting of the graphics and whether there is a screen preview display, or the data is written to a file, or in regards to the graph size or orientation, the setting of options enables the individual to trim down the procedural statements, code in axis and legend definitions. (UCLA Academic Technology Services, 2012, paraphrased)

The work of Friendly (nd ) reports that statistical graphics has as its goal gaining insight into the data and states that SAS/GRAPH procedures alone "often do not go far enough in providing the tools for the most effective visual displays and reports on some useful graphic displays that cannot be produced by the basic SAS/GRAPH procedures and shows how they can be constructed by general macro programs applicable to any dataset." (p.1) Friendly (nd) states that the basic SAS/GRAPH procedures make provision of "a wide range of methods for graphic display of data -- including charts (pie charts, bar charts, 3-D block charts) scatterplots (with points, needles, bubbles, regression lines, etc.), 3D plots (scatter, surface or contour) as well as facilities to display geographical data on a variety of maps." (Friendly, nd, p.2) Friendly writes that making the provision for the basic construction of custom graphic displays are "Annotate, PROC GREPLAY and SAS/IML." (nd, p.2) Each of these are explained as follows:

(1) SAS/IML -- a full-featured language for statistical computation and graphics on its own. Especially useful in applications that require computation on a data seta as a whole, such as finding row and column means or which are naturally expressed in matrix operations, such as calculating a data elliprse for a bivariate scatterplot." (Friendly, nd, p.2) SAS/IML is reported to contain a "powerful and relatively complete set of high-level graphics functions that can be used in the implementation of "customized graphic displays." (Friendly, nd,…