Automation and the Map Label Placement Problem: A Comparison of Two GIS Implementations of Label Placement

Abstract

The placement of feature name labels on maps has challenged mapmakers throughout history. Before the development of mapping software, placing labels in manual map production could consume up to half or more of overall map production time. This paper explores the extent to which current GIS software can place labels legibly, without overlap, and with good visual association between features and labels. This evaluation takes place in the context of a densely featured municipal sewer utility map book. The primary research objective is to evaluate the ability of current GIS software to automate label placement; the research also identifies factors that make manual refinement of automated label placement necessary in order to complete the labeling process. The research compares map-labeling tools from ESRI TM ’s ArcMap TM 9.2: the Standard Labeling Engine and the Maplex TM labeling extension. Label placement success is assessed by both quantity and quality metrics, using a methodology developed and tailored specifically for evaluation of sewer map label placement. The research found that Maplex placed almost seven percent more labels overall than the Standard Labeling Engine. For the labels they did place, both products provided equally good quality label placement: About 93 percent of labels were placed with no overlap, and virtually 100 percent of labels were placed in their preferred position. After conversion to annotation, manual label position refinement eliminated all overlaps but at the cost of a nine percent decline in the preferred position metric.