ABSTRACT

Usually, correspondence analysis is motivated in graphical language. It is often said, in this context, that “A picture is worth a thousand numbers.” Complicated multivariate data are made more accessible by displaying the main regularities of the data in scatterplots. This graphical approach is outlined in considerable detail in the books mentioned above. We merely give a brief introduction, which differs in some important aspects from earlier ones because it emphasizes the graph plot and the star plots (defined below). This type of introduction, which discusses the data analysis tech­ nique as a graph-layout method, was first dicussed in the review articles by Hoffman and de Leeuw (1992) and Michailidis and de Leeuw (1998). We

think it nicely captures the essential geometric characteristics of the tech­ nique.