Point set labeling with sliding labels

This paper discusses algorithms for labeling sets of points in the plane, where labels are not restricted to some finite number of positions. We show that continuously sliding labels allows more points to be labeled both in theory and in practice, WC define six different models of labeling, and analyze how much better-more points get a label-ne model can be than another. Maximizing the number of labeled points is N&hard, but we show that all models have a polynomiallimo approximation scheme, and all models have a simple and eflicient factor-4 approximation algorithm. Finally, we give experimental results based on the factor-i approximation algorithm to compare the models in practice.

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