studies have sampled only a limited range of forensi-
cally relevant variables and, indeed, a limited array of
levels on each of those variables, they have at least
used several different sets of stimulus materials and
events (including both central and peripheral targets)
that have given rise to different rates of correct and
false identifications, different retention intervals
between encoding and test (with the longest being
1 week); varied the similarity of lineup targets and
foils; and varied the lineup instructions.
Studies with adult participants have presented cali-
bration curves, for positive identification responses (or
choosers), that roughly parallel the ideal calibration
curve. In other words, as confidence increases so too
does accuracy in a systematic manner, a pattern not
suggested by the typically modest CA correlations
reported in these same studies. Generally, however, the
curves indicate some degree of overconfidence, with
accuracy rates at the high end of the confidence scale
(i.e., 90% to 100% confident) typically around the
75% to 90% level. In contrast, no such systematic pat-
terns have been detected for participants who rejected
the lineup (i.e., nonchoosers). Three other findings are
also noteworthy. First, in association with confidence
estimates of 90% to 100%, diagnosticity ratios—
indicating the ratio of hits to false alarms—were sub-
stantially higher than for lower confidence estimates.
Second, participants whose identification responses
were very fast were better calibrated than those whose
identifications were slow. The latter finding is to be
expected given that participants with an exceptionally
strong memory for the culprit should not only identify
the culprit when present in the lineup, and be appropri-
ately confident, but should also be less likely to falsely
identify an innocent suspect, thereby reducing the like-
lihood of confident, incorrect responses. Third, there is
some evidence that interventions designed to improve
adults’ scaling of confidence judgments (by causing
them to reflect carefully on the encoding and identifi-
cation test conditions or the possibility that their iden-
tification decision could be mistaken) can reduce
overconfidence and improve CA calibration.
It is encouraging that similar patterns of CA cali-
bration findings have also been reported in a number
of studies using various forms of a face recognition
paradigm, the basic requirement of which is to judge
whether or not faces presented at test had been among
an array of faces that had previously been presented in
a study phase. Specifically, these studies have demon-
strated robust CA calibration for positive (but not
negative) decisions in both absolute and relativejudgment versions of the face recognition paradigm,
but with overconfidence more pronounced as task dif-
ficulty increased (e.g., shorter stimulus exposure dura-
tions at either study or test).
One feature of the calibration studies that must
be highlighted is that the confidence judgments from
participant witnesses were obtained immediately
after the identification response, thereby ensuring
that they were not affected by any postidentification
influences (e.g., from the lineup administrator or
other witnesses) that are known to exert a profound
influence on confidence judgments quite independent
of the accuracy of the identification response. Thus,
while the calibration studies illustrate meaningful CA
relations, eyewitness researchers are in strong agree-
ment that confidence assessments provided after
some delay (e.g., in the courtroom) are potentially
highly misleading about the likely accuracy of an
identification.
Not all the evidence on the CA relation obtained
with the calibration approach is positive about the CA
relation. For example, research done with samples of
children aged 10 to 13 years highlights poor CA cali-
bration and extreme overconfidence, illustrated by
accuracy rates sometimes as low as 30% in associa-
tion with confidence judgments of 90% to 100%.
Furthermore, children’s overconfidence in their iden-
tifications has, thus far, proven resistant to interven-
tions designed to reduce it.Applied Implications
While there is still much to be done in terms of testing
the generality of findings obtained via the calibration
approach across a variety of forensically relevant con-
ditions, the present findings are, nevertheless, impor-
tant from an applied perspective. As indicated earlier,
while the CA correlation addresses the group-level
variance in accuracy explained by confidence, the cal-
ibration approach provides the additional insight into
the likely accuracy of particular identifications made
with some specific level of confidence. The available
data strongly suggest that police investigators should
pay close attention to witnesses’ confidence estimates
solicited at the time of the identification and, hence,
not subject to any social influence. Specifically,
extremely confident (and rapid) identifications of the
suspect in the lineup, while by no means guaranteed to
be accurate, should signal to police investigators that
there is a very real chance that the suspect is the culprit
and, thus, stimulate a closer search for supportive140 ———Confidence in IdentificationsC-Cutler (Encyc)-45463.qxd 11/18/2007 12:41 PM Page 140