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Powerful Statistics with SYSTAT
SYSTAT should have a familiar feel for most users. It imports data from a wide array of sources, including open SYSTAT 9.0 database connectivity sources and text, Excel, and dBASE SPSS, Inc. files. Statistical functions are performed by using pull233 S. Wacker Dr. down menus and toolbars; typing commands in the comEleventh Floor, Ste. 1100 mand pane; or executing saved scripts. When additional Chicago, IL 60606 input is needed, dialog boxes with meaningful default val800-521-1337 or 312-651-3434 ues prompt the user. The output is displayed and organhttp://www.spss.com ized in a Windows Explorer-style window, making it easy $1299 list; $299 upgrade; inquire about other pricing to copy and paste presentation-quality tables and graphs to Requires: Windows 95, 98, or NT other locations or applications. An organizer pane shows the folders, tables, and graphs, and an output pane disSYSTAT 9.0 is a large statistical package that is very well plays tables and graphs. suited for exploratory data analysis and the discovery of In addition, SYSTAT has a spreadsheet-style window, relationships in multivariate data sets. Years ago, SYSTAT which allows data to be easily viewed and edited. Within was developed as a DOS program and was one of the first the spreadsheet window, individual cases (rows) are dyto offer both high-resolution graphics and statistics. Over namically linked to plots. Tools such as lassos can be used the years, it has evolved into a stable, high-quality, Winto select points on the plots, and selected cases are then dows-based application with a substantial array of statistimarked in the data window. Subsequent statistical and cal methods and graph types. graphics commands use only the selected cases. This Experts in statistics will be approach has become standard in pleased to find that the statistical most modern statistical software methods include analysis of variance packages, but it is not as straightforand other descriptive statistics; ward in SYSTAT as in other softhypothesis tests; design of experiware packages. ments; factor, discriminant, cluster, SYSTAT also has several other and time-series analyses; mapping; rough spots. Compared with dedistandard and nonlinear regression; cated graphing programs, it lacks and multidimensional scaling. In some flexibility for formatting addition, the graph types include graphs. In particular, most formatbar, line, box, scatter, and density ting must be set before the graph is plots; histograms; maps; and probagenerated and cannot be changed bility and quality control charts. later. However, one way around this Even chemists with a moderate Sample output using SYSTAT. The organizer limitation is to produce copies with pane and various graph types are shown. background in statistics will find the modified format settings, which is program immediately useful. All of very easy to do. Another drawback the major statistical methods have is that the organization of options dialog boxes with default settings that can be used to and items in dialog boxes is sometimes confusing and obtain useful results in a very short amount of time. In makes some statistical and graphing tasks difficult. For addition, extensive programming and scripting features example, to add a regression line and confidence intervals make it possible to automate routine analysis tasks. to a scatter plot, options must be set under the “smoothThe program’s substantial online help system gives ing” command in the scatter-plot dialog box. However, users instant access to definitions, tutorials, and examples these problems are fairly minor. Of more concern to for all methods. This help system is one of the program’s chemists is the absence of a partial least squares tool, greatest strengths. With it, motivated users who possess a which is frequently used for multivariate spectroscopic basic understanding of statistics can use SYSTAT as a selfcalibration. paced learning tool. The Design of Experiments wizard Nevertheless, SYSTAT reflects a long history of careful provides an outstanding example of its tutorial capabilities. programming and user-interface design. It is a powerful Suppose the user selects a Placket–Burman design. To tool that provides a large selection of statistical and graphiguide the user, the wizard presents a series of questions cal tools for scientists and statisticians, and the extensive about the numbers of factors and levels to be used. By online help, tutorials, and examples make the program pressing the help buttons at any stage during the process, accessible to most users. the user can get definitions of these terms and contextually relevant tutorials and examples. Reviewed by Paul J. Gemperline, East Carolina University
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