Table 5 Results of statistical analyses (Mann-Whitney rank sum test for the pitcher 1, 0 vs. 4 weeks; t-test for all other comparisons) of the wax coverage height measurements on the mechanically manipulated pitcher surface. The normality and equal variance tests passed for all data sets except pitcher 1, comparison 0 vs. 4 weeks (normality test failed, P < 0.050). d. f., degrees of freedom; No, no significant difference; P, probability value; t, t-test statistics; T, Mann-Whitney rank sum test statistics; Yes, significantly different
Comparison | Pitcher 1 | Pitcher 2 | Pitcher 3 | Pitcher 4 | Pitcher 5 |
|---|---|---|---|---|---|
0 vs. 4 weeks | T = 232.000 P = 1.000 No | t = 1.521 d. f. = 28 P = 0.139 No | t = 0.782 d. f. = 28 P = 0.441 No | t = 0.492 d. f. = 28 P = 0.626 No | t = −0.004 d. f. = 28 P = 0.844 No |
4 vs. 8 weeks | t = −2.388 d. f. = 28 P = 0.024 Yes | t = −0.912 d. f. = 28 P = 0.370 No | t = −0.438 d. f. = 28 P = 0.665 No | t = −1.430 d. f. = 28 P = 0.164 No | t = 0.134 d. f. = 28 P = 0.894 No |
