Table 2.
Mean, standard deviation, and F values from one-way ANOVAs examining variation in the acoustic parameters describing screams given by 21 individuals to severe aggression as a function of audience composition
| High-ranking bystander present (n = 12) |
High-ranking bystander absent (n = 9) |
F value | P value | |||
|---|---|---|---|---|---|---|
| Mean | SD | Mean | SD | |||
| Rate | 1.28 | 0.25 | 1.65 | 0.56 | 4.234 | 0.054 |
| Bout length | 13.08 | 6.08 | 14.88 | 7.35 | 0.379 | 0.545 |
| Duration | 0.58 | 0.14 | 0.39 | 0.15 | 8.662 | 0.008 |
| Mean F0 | 702.02 | 44.38 | 646.88 | 101.29 | 2.864 | 0.107 |
| Peak time | 0.406 | 0.12 | 0.254 | 0.11 | 8.809 | 0.008 |
| Peak frequency | 1,491.29 | 130.76 | 1,351.11 | 186.64 | 4.114 | 0.057 |
| First formant | 1,390.21 | 92.81 | 1,289.78 | 142.06 | 3.847 | 0.065 |
| Transition onset | −179.04 | 112.20 | −147.67 | 114.87 | 0.394 | 0.538 |
| Transition offset | 200.29 | 93.03 | 101.39 | 96.38 | 5.639 | 0.028 |
Degrees of freedom: 1,20.