RICHARD R. BATSELL "We first survey the plot, then draw the model, rr Shakespeare, King Henry IV, Part II, Act I, Sc.3 The visual presentation of a set of data facilitates its under- standing and explanation. This paper describes how hidden surface routines can be used to construct two-dimensional portrayals of three-dimensional data. Data from a study on consumer preferences is used to illustrate the process. ON THE USE OF HIDDEN SURFACE ROUTINES IN THE ANALYSIS OF MARKETING DATA W ITHOUT question, the visual presentation of a set of data facilitates its interpretation. Whether the phenomenon under study is represent- ed as the location of points in N-space, or the functional relationship between a set of independent variables and a dependent variable, visual inspection of the data or the model can lead to considerable insight. This is as true for the market researcher seeking to build a model, as it is for the marketing manager seeking to understand the preference structure of a segment of consumers. However, with the exception of some studies of the geographicaldistribution of demand and other phenomena (Harvard Library of Computer Mapping 1979; Tektronix 1974), visual presentation of mar- keting data has been constrained to two dimensions. Richard R. Batsell is Assistant Professor of Administrative Science, The Jones School, Rice University, Houston. The author would like to thank Toni Patti of the Wharton Computation Center for help in the implementation of the computer routines described, and Joshua Greenberg for help in the collection of the data used to illustrate the routines. 102 / Journal of Marketing, Summer 1980 In some cases, eventhe presentation of geographical data which are naturally three-dimensional has been reduced to two-dimensions through the use of isarithmic maps (Applebaum 1966; Huff 1962, 1964; MacKay 1973). There seem to be two reasons for reliance on two-dimensional portrayals of three-dimensional data: lack of availability of computer software, and lack of appreciation of the insights that can be derived from a three-dimensional presentation. The purpose of this brief paper, therefore, is to offer a set of routines that use transformations and perspective to portray a three-dimensional surface (or set of points) on a two-dimensional surface. Insights that can be gained from visual inspection of these surfaces are demonstrated using data from a study on consumer preferences for notebook paper. The Application of Hidden Surface Routines to the Analysis of Marketing Data-One Example In an attempt to apply a methodology for the modeling of choice, the author had 16 actual Journal of Marketing Vol. 44 (Summer 1980), 102-106.