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CHAPTER 11: Data Analysis and Interpretation: Part I. Describing Data, Confidence Intervals, Correlation 349butler (not the cook) might have done it. Abelson (1995) makes a similar pointregarding a research argument:High-quality evidence, embodying sizeable, well-articulated and general effects,is necessary for a statistical argument to have maximal persuasive impact, but itis not sufficient. Also vital are the attributes of the research story embodying theargument. (p. 13)Consequently, when data analysis is completed, we must construct a coherentnarrative that explains our findings, counters opposing interpretations, andjustifies our conclusions. In Chapters 12 and 13 we’ll return to the analysis storywhen we introduce guidelines to help you develop an appropriate narrative foryour research study.COMPUTER-ASSISTED DATA ANALYSIS• Researchers typically use computers to carry out the statistical analysisof data.• Carrying out statistical analyses using computer software requires that theresearcher must have a good knowledge of research design and statistics.Most researchers have ready access to computers that include appropriatesoftware to carry out the statistical analysis of data sets. The ability to set upand carry out an analysis using a statistical software package and the abilityto interpret the output are essential skills that must be learned by researchers.Some of the more popular software packages are known by ab breviations likeBMDP, SAS, SPSS, and STATA. You likely have access to one or more of theseprograms on the computers in your psychology department or at your campuscomputer center, or perhaps even on your laptop.Carrying out statistical analyses using computer software requires that theresearcher have a good knowledge of research design and statistics. In Chap -ters 6, 7, and 8 we introduced various experimental designs. This knowledgeis essential if you wish to use computer-assisted analysis. A computer is notable to determine what research design you used or the rationale behind theuse of that design (although some of the user-friendly programs provideprompts to guide your thinking). To carry out computer-assisted data analysis,you must enter information such as the type of design that was used (e.g.,random groups or repeated measures); the number of independent variables(e.g., single factor or multifactor); the number of levels of each independentvariable; and the number of dependent variables and the level of measurementemployed for each. You must also be able to articulate your research hypothesesand to plan appropriate statistical tests of your research hypotheses. Acomputer will quickly and efficiently perform the computations necessary forobtaining descriptive and inferential statistics. To use the computer effectivelyas a research tool, however, you must give it specific directions regardingwhich statistical test you want it to perform and which data are to be used incomputing the test. Finally, when the computer has carried out the computations,you must be able to interpret correctly the output showing the results ofthe analysis.