=+4.34 ● The article “Compression of Single-Wall Corrugated Shipping Containers Using Fixed and Floating Test Platens” (Journal of Testing and Evaluation [1992]: 318–

320) described an experiment in which several different types of boxes were compared with respect to compressive strength. Consider the following observations on four different types of boxes (these data are consistent with summary quantities given in the paper):

Type of Box Compression Strength (lb)

1 655.5 788.3 734.3 721.4 679.1 699.4 2 789.2 772.5 786.9 686.1 732.1 774.8 3 737.1 639.0 696.3 671.7 717.2 727.1 4 535.1 628.7 542.4 559.0 586.9 520.0