computer for summary data

Using a Computer to Calculate Summary Numbers A personal computer, either a PC or a Mac, is very frequently used with a spreadsheet to calculate the summary numbers we have been discussing. One of the spreadsheets used most frequently by engineers is Microsoft® Excel, which includes a good number of statistical functions. Excel will be used in the computer methods dis-cussed in this book. Using a computer can certainly reduce the labor of characterizing a large set of data. In this section we will illustrate using a computer to calculate useful summary numbers from sets of data which might come from engineering experiments or measurements. The instructions will assume the reader is already reasonably familiar with Microsoft Excel; if not, he or she should refer to a reference book on Excel; a number are available at most bookstores. Some of the main techniques useful in statistical calculations and recommended for use during the learning process are discussed briefly in Appendix B. Calculations involving formulas, functions, sorting, and summing are among the computer techniques most useful during both the learning process and subsequent applications, so they and simple techniques for producing graphs are discussed in that appendix. Furthermore, in Appendix C there is a brief listing of methods which are useful in practice for Excel once the concepts are thoroughly understood, but they should not be used during the learning process. The Help feature on Excel is very useful and convenient. Access to it can be obtained in various ways, depending on the version of Excel which is being used. There is usually a Help menu, and sometimes there is a Help tool (marked by an arrow and a question mark, or just a question mark). Further discussion and examples of the use of computers in statistical calcula-tions will be found in section 4.5, Chapter 4. Some probability functions which can be evaluated using Excel will be discussed in later chapters. Example 3.4 The numbers given at the beginning of section 3.2 were as follows: Group A: Group B: Group C: 2, 3, 4, 81, 2, 4, 100, 1, 5, 11