ABSTRACT

This chapter presents approaches for modifying raw data for three main purposes: (1) standardization for the purpose of making comparisons between different contexts; (2) transformation for the purpose of “normalizing” one’s data; and (3) aggregation for the purpose of summarizing data belonging to different contexts for comparative analysis. The chapter outlines some considerations for the calculation of ratios and percentages, logarithmic and square root transformations, and summarizing data for the purposes of aggregation. It also discusses how these modifications of raw data relate to the assumptions of various statistical analyses.