ABSTRACT
This chapter focuses on selecting projections for data that are considered discrete and abrupt. It examines the implication of projection on proportional point and flow maps. The chapter discusses four important design considerations when choosing projections for proportional symbol maps. First, consideration should be given to the projection class. Second, the projection aspect determines where the geographic center of the map is and can influence the arrangement of the proportional symbols around that center. Third, projections display the poles as points or pole lines of various lengths, which can be an aesthetic concern. Fourth, projections can show interruptions that divide the oceans or landmasses into lobes. The projection class can have a significant effect on the overall appearance of the proportional symbol map. The projection aspect can be thought of as centering the projection over a particular location. Any projection can be centered, which aligns a particular geographic area of interest to the map’s center.
