“…Martilla and James (1977) suggested mean importance values should be plotted against mean performance values, and others have subsequently followed this approach (Crompton & Duray, 1985). Grand mean (mean of all mean scores) was the most frequently used technique (34%) of 42 IPA studies analyzed (Janes & Wisnom, 2003). Janes and Wisnom (2003) further found, however, that grid line placement was often determined in various ways.…”