Table 1
Truth ratings (scale 1–6) for new and repeated statements. Standard deviations in parentheses. Truth effects are calculated as the difference between repeated and new statements ratings. Accent effects are calculated as the difference between native-accent and foreign-accent ratings.
| ILLUSORY TRUTH | NEW | REPEATED | TRUTH EFFECT |
|---|---|---|---|
| Native accent | 3.58 (1.26) | 4.17 (1.38) | .59 |
| Foreign accent | 3.50 (1.40) | 4.15 (1.53) | .65 |
| Accent effect | .08 | .02 | –.06 |
Figure 1
Plot effects of the interaction model on truth ratings. An illusory truth effect of the same amount was observed in both Foreign and Native-accented groups.
Table 2
Results from the 109 evaluators who rated 11 social traits, intelligibility, and perceived accent of the voices used in the main experiment. The asterisk (*) indicates the ratings on intelligibility and perceived accent of the participants who completed the main experiment.
| NATIVE | FOREIGN | STATISTICS (COMPARISON) | |
|---|---|---|---|
| Brilliant | 4.82 (1.24) | 4.45 (.99) | Estimate = .80; S.E. = .19; z = 4.11 |
| Educate | 5.62 (1.14) | 5.74 (1.04) | Estimate = –.30; S.E. = .19; z = –1.57 |
| Smart | 4.63 (1.03) | 4.45 (.88) | Estimate = .52; S.E. = .21; z = 2.43 |
| Competent | 5.2 (1.47) | 4.69 (1.53) | Estimate = 1.62; S.E. = .24; z = 6.61 |
| Successful | 4.5 (1.38) | 3.86 (1.08) | Estimate = 1.16; S.E. = .19; z = 6.06 |
| Friendly | 4.68 (1.62) | 4.55 (1.42) | Estimate = .24; S.E. = .19; z = 1.28 |
| Funny | 4.38 (1.17) | 4.09 (1.31) | Estimate = .39; S.E. = .18; z = –2.13 |
| Pleasant | 5.16 (1.23) | 4.89 (1.22) | Estimate = .52; S.E. = .18; z = 2.89 |
| Honest | 4.72 (1.74) | 4.14 (1.77) | Estimate = .73; S.E. = .18; z = 3.96 |
| Sociable | 4.39 (1.22) | 4.37 (1.11) | Estimate = .13; S.E. = .18; z = .69 |
| Trustworthy | 5.54 (1.18) | 5.39 (.99) | Estimate = .49; S.E. = .20; z = 2.42 |
| Intelligibility | 6.34 (.97) | 5.68 (1.25) | Estimate = 1.93; S.E. = .07; z = 26.84 |
| Perceived accent | 1.64 (1.38) | 5.96 (1.54) | Estimate = –4.66; S.E. = .09; z = –48.48 |
| Intelligibility* | 5.30 (1.02) | 5.07 (1.19) | Estimate = .62; S.E. = .36; z = 1.73 |
| Perceived accent* | 4.16 (1.72) | 1.59 (1.04) | Estimate = –3.74; S.E. = .32; z = –11.8 |
Appendix A
Statistics of model selection for illusory truth effect analysis. The model which best explained the data is m4, which included the interaction Repetition × Accent × Order as fixed effects.
| MODEL | EFFECTS | DF | AIC | BIC | p-VALUE |
|---|---|---|---|---|---|
| m0 | ~1 + R.E. | 15374 | 15418.94 | ||
| m1 | Repetition + R.E. | 1 | 15092 | 15143.37 | <.001 |
| m2 | Repetition + Accent + R.E. | 1 | 15094 | 15151.75 | .79 |
| m3 | Repetition + Accent + Order + R.E. | 1 | 15183 | 15247.29 | 1.00 |
| m4 | Repetition * Accent * Order + R.E. | 4 | 15091 | 15181.39 | <.001 |
[i] Note. R.E. refers to Participant and Item, which were added as random effects in the model. DF = Degrees of Freedom. AIC = Akaike information criterion; BIC = Bayesian information criterion.
Appendix B
Reported statistics speaker’s traits influence to the model of interest (see main text for details).
| TRAIT | STATISTIC |
|---|---|
| Brilliant | Estimate = –.001; S.E. = .06; z = .61; p = .98 |
| Smart | Estimate = .03; S.E. = .11; z = .30; p = .76 |
| Competent | Estimate = .08; S.E. = .10; z = .79; p = .43 |
| Success | Estimate = .003; S.E. = .07; z = .04; p = .96 |
| Funny | Estimate = .001; S.E. = .06; z = .02; p = .98 |
| Pleasant | Estimate = .04; S.E. = .07; z = .61; p = .53 |
| Honest | Estimate = .11; S.E. = .09; z = 1.22; p = .22 |
| Trustworthy | Estimate = .007; S.E. = .09; z = .07; p = .94 |
| Perceived accent | Estimate = –.02; S.E. = .07; z = –.24; p = .80 |
| Intelligibility | Estimate = .23; S.E. = .15; z = 1.52; p = .12 |
| Perceived accent* | Estimate = –.009; S.E. = .04; z = –.20; p = .83 |
[i] Note. *Indicates rate on perceived accent of the participants who completed the main experiment.