OUTSIDE AND INSIDE THE REGRESSION BLACK-BOX FROM EXPLORATORY TO INTERIOR DATA-ANALYSIS

Good data analysis consists of three phases: (1) preliminary analysis, (2) confirmatory analysis (model testing), and (3) interior analysis (model checking). Social scientists doing quantitative research usuall y concentrate on only one of the three: confirmatory analysis. I argue that there is much to be learned from careful preliminary and interio r analyses. I present an extensive example of data analysis for each o f the three phases using the same data set in each phase. Rather than surveying all the possible tools available in each phase of data analy sis, I concentrate on Exploratory Data Analysis techniques (stem-and-l eaf plot, letter-value display, box plot, and power transformations) f or the preliminary phase, on OLS for the confirmatory phase, and on re siduals, leverage and single-case influence measures for interior anal ysis.