Computers are now available to students at most colleges and universities. Spreadsheets, such as Microsoft Excel, and statistical software packages, such as MINITAB, are available in most computer labs. The Microsoft Excel package is bundled with many home computers. In this text we use both Excel and MINITAB for the applications. We also use an Excel add-in called MegaStat. This add-in gives Excel the capability to produce additional statistical reports.

The following example shows the application of computers in statistical analysis. In Chapters 2, 3, and 4 we illustrate methods for summarizing and describing data. An example used in those chapters refers to the price reported in thousands of dollars of 80 vehicles sold last month at Whitner Autoplex. The following Excel output reveals, among other things, that (1) 80 vehicles were sold last month, (2) the mean (average) selling price was $23,218, and (3) the selling prices ranged from a minimum of $15,546 to a maximum of $35,925.

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The following output is from the MINITAB system. It contains much of the same information.

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Had we used a calculator to arrive at these measures and others needed to fully analyze the selling prices, hours of calculation would have been required. The likelihood of an error in arithmetic is high when a large number of values are concerned. On the other hand, statistical software packages and spreadsheets can provide accurate information in seconds.

At the option of your instructor, and depending on the software system available, we urge you to apply a computer package to the exercises in the Data Set Exercises section in each chapter. It will relieve you of the tedious calculations and allow you to concentrate on data analysis.