Fig. 2: Vocal size deception biases judgements of body size (Experiment 1).
From: Efficacy in deceptive vocal exaggeration of human body size
a Bias in height judgements shown as the mean difference (±SEM) between perceived and actual heights of vocalisers, in cm, for honest vocal signals (central blue bars) and deceptive vocal signals (attenuating size = grey bars, exaggerating size = red bars), where 0 indicates accurate height judgements, positive values indicate overestimation, and negative values indicate underestimation. Estimated marginal means and pairwise comparisons derive from linear mixed models, LMMs (see Supplementary Table 5), where all ***p < 0.001 following Šidák correction for multiple comparisons. Tests are two-tailed. Error bars represent standard errors of the mean, ±SEM. See also Supplementary Fig. 1 for dot plots illustrating the distribution of data. b Linear regressions showing relationships between perceived and actual heights of vocalisers, where each dot represents a vocaliser, and height judgements are averaged across listeners for each vocaliser and each size condition (exaggerating size = red circles, honest = blue squares, attenuating = grey triangles), where Cook’s Di < 0.20 (see Methods). 1 cm on the x-axis is equal to 1 cm on the y-axis. Spearman’s rho (rs) correlation coefficients are given for each regression line, where *p < 0.05, one-tailed (males exaggerating r = 0.48, p = 0.02, n = 18; honest r = 0.44, p = 0.03, n = 19; attenuating r = −0.17, p = 0.25, n = 18; females exaggerating r = 0.35, p = 0.06, n = 20; honest r = 0.54, p = 0.01; n = 18; attenuating r = 0.50, p = 0.02; n = 18). All data were derived from Experiment 1 based on 120 vocal stimuli produced by n = 40 vocalisers (20 males, 20 females) in each of three size conditions (honest, attenuating, exaggerating) and judged by n = 97 listeners, where each vocal stimulus was rated by an average of 50 listeners (see Methods). Source data are provided as a Source Data file.
