The accuracy of perceived trustworthiness
Recall from Study 1 that a deception index was calculated for each dater. The judges’
trustworthiness ratings were not correlated with this deception index (r = −0.02,
ns), suggesting that their perceptions of the daters’ trustworthiness were not accurate.
To calculate the more traditional accuracy rate used in deception detection
research, the data were prepared for a 2 (high vs. low trustworthiness) ×2 (perceived
high vs. perceived low trustworthiness) classification. The deception index was used
to classify online daters into high and low trustworthiness categories using a median
split (Mdn = −0.16). Then, the judges’ ratings were used to categorize daters into
low and high perceived trustworthiness by dichotomizing the 7-point Likert scale
used. The midpoint of the scale (i.e., 4) or higher was classified as high perceived
trustworthiness and a score below 4 was classified as low. The midpoint rather than
the median of the perceived trustworthiness scale was used to assess truth bias (i.e.,
more daters being perceived as trustworthy than untrustworthy).
Judges’ accuracy rate in categorizing daters as high or low in trustworthiness
was 48.7%, not different from chance, suggesting that the judges were unable to
classify daters on trustworthiness from their textual self-descriptions. Consistent
with previous research on deception detection, an important reason for the low
detection rate was the operation of the truth bias: Judges only classified 14 of the 78
daters (18%) as not trustworthy (see Table 3).