A Visual Treatment of the N-Puzzle

Informed search strategies rely on information or heuristics to find the shortest path to the goal. Understanding the intricacies of these search strategies and the heuristics they employ is of great importance to AI research. Visualizations of a search space may provide some insight. However, visualizing large hierarchical data can be challenging. Traditional graph visualizations such as top-down or left-right tree layouts would yield massive images that are difficult to navigate or distill any useful information at a glance. In this paper we evaluate an interactive visualization for large tree structures. We use these visualizations to explore the search spaces of the 8-Puzzle. We show how this interactive visualization can be used to compare two common heuristics for the 8-Puzzle.