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Complete listing of June 1996 reviews
by Joel T. Patz
Sometimes "lies, damned lies and statistics" are generated by error, not design. But Statgraphics Plus 2.0 offers explanations like "This analysis compares horsepower to price," which might keep you on track when you're not sure where your numbers are heading.
The program's StatAdvisor warns you if data violates critical assumptions and suggests other statistical procedures. It's far from perfect; it didn't help me spot a field 5,000 times higher than the rest. But its advice could be helpful for statistical novices.
You can add StatAdvisor's judgments to a word processor document. You'll have to copy its interpretations manually, however, since the program's OLE 2.0 support doesn't work well in Microsoft Word.
The statistical heart of Statgraphics Plus is rich in statistical tests, with over 150 statistical procedures, from simple, multiple and polynomial regression to 22 different varieties of probability distributions.
Statgraphics Plus can import data from Excel, Lotus 1-2-3, dBASE, ASCII and DIF files. You can perform some 100 data transformations, from treating a date as a number to accumulating data into distinct ranges. The program's add-on modules perform quality control, experimental design, time-series and advanced multivariate analysis.
Once you've chosen variables and selected statistical tests, Statgraphics Plus performs the analysis and explains the results. It comments on possible errors and pitfalls, and selects the graphing options suitable for your analysis.
Unfortunately, Statgraphics' very basic graphing tools aren't equal to a spreadsheet's. I expected to be able to manipulate labels, grids and colors, but I couldn't control individual elements. Given Statgraphics' heavy statistical power and price, this is a serious limitation.
The program presents your test results on a single screen; the interactive interface helps you drill down to actual numbers. Clicking on a data point within the graph automatically reveals its source in the table
You can save your graphics and results as StatFolios, a convenient way to bookmark data for repeated analyses. I was able to change several variables in a StatFolio, looking for variances in the outcome, and was pleased with the speeds of subsequent runs. You can choose to print any part of your work or the entire StatFolio, another convenience.
The program's documentation not only tells you how to perform an analysis, but gives real-world examples of when, why and how you'd use tests. Each possible graphing option, and type of graph, is described in detail. Wonder what a Box-and-Whisker plot tells you? The documentation explains it all. The program uses colorful icons and bubble help, with good online help, but not much is customizable.
Statgraphics Plus is a good choice for the less experienced statistician, with enough analytical power to keep more demanding users happy. If Manugistics adds modern graphing techniques, Statgraphics could move to the head of its class.
Info File
Statgraphics Plus 2.0
Price: Base system, $649; each module, $399; complete
system, $1,599
Pros: Documentation; ease of use; speed
Cons: Graphing
Platforms: Windows 95, 3.1x, NT
Disk Space: 8MB
RAM: 8MB (16MB recommended)
Manugistics
800-592-0050, 301-984-5000
WinMag Box Score 3.0
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