Transcript Psychology323withbtsr_000

J. P. Rosenfeld, Ph.D.
[email protected]
We should spend an equal
time on phenomenology and
MECHANISMS of deception….
…as we do on DETECTION of
deception. But there is a lot more
research-based (real) knowledge
about the latter, so most of the
time, that’s what we will cover.
Regarding detection; there are
two approaches:
1. Behavioral
(a) non-verbal
(b) Verbal
2. Physiological: Nervous
system activity.
….We start with Behavioral:
Are the following notions True?
1. People typically reveal their lies by fidgeting, acting
 nervous, avoiding eye contact, etc.
2. Therefore, we are rather good lie detectors (unless we are
very stupid).
3. This is especially true when we detect lies in those close to
us.
4. Criminals, con-men, professional crooks, and such,
however, are harder to spot for us lay people.
5. Fortunately, trained professionals (police, FBI) are superior
lie detectors, so they protect us against pros.
We wish we
had a
Pinocchio's
nose
indicator
But we don’t…
…NONE of those assertions
is true!
People think they are
great lie detectors.
But they miss many
lies. Why?
 (1a) If someone thinks
you look great, why
argue? (Vrij: Ostrich
effect)
(1b) I’ll ask no
questions……(and hope
you tell no lies!)
Bill to Hillary and to an
aide: “Ah did not have
sex with that woman…..”
(2) Lie detection is
tough!
 There is no behavioral or
physiological specific index of
deception, though things are not
as bad a Vrij suggests: P300, fMRI
Beware of internet & Media claims!
 Pavlidis’ thermal imaging not so
great…
 BEOS Brain Electrical Oscillations
Signature is Bogus!
 “Brain Fingerprinting?!” (See my
critique….)
How common is lying?
 A) once a year?
 B) once a month?
 C) once a week?
 D) More than daily?
Definition of lying:

OK, give one…
Intentional, without
warning, misinform or
mislead another.
Liar must believe
information is false.
Lie could fail.
(Types of Lies)
From Bad-est to least bad:
 (1) Outright Lie– (total B.S.)
 John Edwards: “I am not the
father of that child, no way, I’ll
happily take a DNA test….”
 He was stating “I didn’t do it”
while knowing he did.
(2)Exaggerations (overstatements)
or Minimizations(understatements)
 “I am the most eminently famous
researcher in the Psych.
Department.” (but almost…)
 “This is an important discovery of
mine not yet published” (which
was actually rejected by one
journal and now in review at
another.)
(3) Subtle Lies (Omit details)
 Clinton: “Ah did not have sex
with that woman, Miss
Lewinski…”
 (Not according to the usual
definition: intercourse.)
(4) Concealment…
 “How was your day?…mine
was as usual…”
 [Heaven forbid she asks me
about my day!]
Many reasons:
 (1) Material Gain
 (2) Avoid loss/punishment
 (3) Avoid embarrassment
 (4) Make good impression (&
get the job)
All these involve
gain for oneself.
The other kind of (Otherdirected) Lie:
Altruistic Lies:
“You made a great impression…”
Telling a gravely ill person (child)
that she will be fine..
Why is it hard to know for sure
how often people lie?
Self report fails
because (1) people
don’t want to recall &
(2) don’t remember.
But 2+ times a day is a
fair estimate.
Whom do people lie to?
Strangers more than
close contacts. (Why?)
(1) Gender:
 Men tell more self-oriented lies.
 Women tell more other oriented
lies
(2) Age
 What is definite minimum age for
lies in children? (2,4,6,8,10) See
Vrij, P. 27.
 What motivates youngest
children’s lies? (Gain of say
cookies? Avoid punishment?
(earliest lies). Make a good
impression?)
(3) Personality Type
 In romantic relations:
 (a) attachment style: avoidant
(lack of trust, keep people at
distance)…..these folks lie to keep
others at a distance.
Versus
 anxious attachments: lack of selfesteem. These people lie to look
good as they feel bad.
(b) Psychopathy
 The types have no empathy or
sympathy for others. They regard
others as pieces of themselves,
and objects of manipulation—like
their own limbs. These are big
time liars to everyone they might
wish to manipulate. Superficially
charming, they get away with it
for a while…
(c) Extraverts and introverts
 Outward/sociable vs. reserved.
 Which are the bigger liars?
(d) Self-consciousness:
 These are very concerned with
impression they make, so how do
they behave with respect to
deception?
In this connection, one speaks also
of social anxiety: they lack self
confidence, so they tell tales.
(Are we all on same page? What
are these?)
We wish we
had a
Pinocchio's
nose
indicator
DiPaolo’s group emphasizes 3
theoretical perspectives:
 During deception, 3 phenomena
occur that may yield “tells”:
 1) emotional reactions: guilt, fear---and delight. (delight?)
 Guilt  low eye contact
 Fear  stuttering, blinks, squeals.
 Delight (of duper) excitement,
inappropriate laughter. (Ekman)
What else does liar experience?
 2) mental (task) demand, also
called cognitive load. Liars will
also tend to look away, so as to
concentrate on made up details.
Except when they monitor you to
see if you believe.
 3) Attempted self control of
behavior to avoid tells. Not easy.
Voices break, facial expressions
occur: Ekman’s micro-expressions.
These are theories of what
should happen. Moreover…
…these effects are affected by
certain other factors, e.g.,
 GUILT—The degree of guilt felt
depends on personality. Consider
Psychopathy. & Consider Stakes.
& Consider sense of righteousness
or duty felt by CIA agent.
 FEAR– Experienced liars of
whatever breed have less fear.
 EXCITEMENT– helped by type of
audience. Also, if it’s a big
conquest, or else, no.
More…
 COGNITIVE LOAD--- also depends on
verbal skill-intelligence and experience.
(Vrij is wrong about Psychopaths
feeling less load.) Degree of rehearsal
also makes a difference (practice
makes perfect!). No transparency
illusion. So more monitoring of other.
 SELF CONTROL depends on
Psychopathy.
Vrij is a pain, but best we
have..(E.g.Box 3.1 p. 47)….
 …and his best statement is on the
top of p. 49. “ …the relationship
between lying and non-verbal
behavior is complex.” The
implications of this statement
regarding development of nonverbal “tells” is what?! (Life is not
Poker.)
Field Studies.(Define.)
 We want to compare liars vs.
truth-tellers, but…
Difficulties:
1)Getting videos: (Are cameras
always running?)
2) Establishing “Ground Truth.”
3) Controls: only possible in lab to
have unconfounded conditions—so
not many field studies re:
nonverbal cues are out there…
What’s a Confound ?
Consider our deception
feedback study:
OK, how about lab studies?
 Pluses: Ground truth easy to get
by design. Likewise, unconfounded control conditions.
 Minuses: Lies are instructed. So
what happens to guilt? fear? What
happens regarding stakes? You
can offer lots of money, but not
punishment (as in real life).
 DECEPTION HARD TO STUDY!
Bottom Line:
 Vrij’s Appendix 3.1(p. 90) makes
very clear that there is NO reliable
non-verbal sign of deception.
There may be trends and even
significant group effects (explain),
which support theoretical views
noted above…..
**But in D of D, the key statistic is
INDIVIDUAL HIT RATE (as utilized
in d’ or AUC from SDT).
Dramatically:
 Is there such a thing as “lyin’
eyes?” Are gaze or eye contact
helpful? (p. 60) Vrij says no, but
there is new research: N. Cohen,
Frank.
*Are liars more emotional than
truth tellers? Why or why not? (p.
61) [HINT: Is it only liars who feel
emotion?]
Table 3.1 (p. 57) in Vrij is about
effect size.
 J. Cohen's d = M1 - M2 / spooled
where spooled = �[(s 1�+ s 2�) / 2]
 In Table 3.1, only 3/18 d values are
> .30 (moderate) in the big meta
analysis of 100 behaviors.
 Remember, d is a GROUP
measure!
Vrij’s “Group Differences”
(p.67)….
Very suspect!
 As is rest of chapter about
Clinton, Saddam Hussein, Huntley.
 Amazing that he says (p.89) look
for the cluster of c(l)ues to
deception, not single c(l)ues.
Which cluster? “There is no
straightforward answer….”
That is….speech signs…
We wish we
had a
Pinocchio's
nose
indicator
Vrij description of possible
verbal signs (“cues”)…
 ….as in his box 4.1 list (p. 101) is
mostly pathetic, i.e., wrong (imho).
 On the other hand, sometimes one
has to say, “duhhh!” as when he
states that direct statements are
more credible than evasive ones.
 Obviously plausibility helps! As
does consistency (lack of
contradiction).
But Vrij best statement is…
 “As I will demonstrate, a verbal
cue uniquely related to deception,
akin to Pinocchio's growing nose,
does not exist.” (p. 103)
 Again, an appendix (4.1 yuk!) shows
some trends & group effects as
supporting some views in Box 4.1.
 Again, clusters> singles. But which
cluster? No one knows.
Vrij indulges himself with
many “I think..” type ideas.
 That’s fine. Be sure you do not
confuse these hypotheses for
facts!
 Note: people & researchers
always start out with what
appears obvious, like twitches &
speech signs. These all are
ultimately controllable, unlike
physiology (looking ahead).
Henceforth….
 We will be looking at more
specialized and developed
approaches to detecting
deception. Vrij still likes “more
immediate” (non-physiological)
tools, because they are allegedly
quick, easy, & cheap. Imho, he
stretches things by emphasizing
how laborious some methods are...
OK,
 fMRI requires a $1M+ machine and an
annual budget of >$1M…
 But when Vrij states (p. 189) that
EEG/ERP recording usually requires 10
or more scalp electrodes, he
exaggerates: 2 (actually 1) will do, and
it takes only 5 minutes to hook up.
 But Vrij & we will go on with SVA, RM &
possibly SCAN, imho, unphysiological
extensions of what we just did…
Reality Monitoring, Statement Validity
Assessment, & Scientific Content
Analysis.
For SVA, go to power point on
323 web site called…..
 “Statement Validity Analysis”
and read Vrij chapter 8. I will
not lecture on it. But I will
lecture on the Implicit
Association Test. Go to this
web site and take a demo test:
 https://implicit.harvard.edu/im
plicit/demo/
Reality Monitoring…
 RM started not as a DoD method,
but rather as a discipline in
Cognitive Psychology to study on a
theoretical basis, the differences
between perceived versus
imagined experience; as with false
(but honestly believed) memories.
What are the characteristics of
Real versus False Memories…..
 …with regard to:
 Sensory Information?
 Contextual Information?
 Affective information?
 Think of dimensions of clarity
versus vagueness?
 Give examples of what you might
actually remember about an event.
This Q & A system of M.
Johnson sorta works, but…
What happens as time
passes?
So what do you remember
better, last week or when
you were 3?
Actually…
 Actually, it turns out that
Physiology (ERPs) come to the
rescue again regarding false
memories… which is good
because RM tool isn’t so great..(p.
265)
 …as we will see later.
If RM is not a perfect false
memory detector, then why..
…would we think this strategy
would be a good deception
detector?
Are there differences between
false memories and deceptions?
HINT: What do subjects believe
about veracity of f.m. and lies?
RM Criteria (Sporer ‘97) some overlap with
CBCA: based on interviews:nonstandardized
 From Vrij Table 9.1. The first 7 should
be there in true statements.
1. Clarity—clear sharp, vivid statements
2. Perceptual info.—details of smell,
sound, etc.
3. Spatial info.—details of location,
seating arrangement, object location.
4. Temporal Info– When things happened,
and in what order.
(continued…)
Four more…
5. Affect detail—How subject felt:” I was
disgusted when I saw the body…”
6. Reconstructability of the testimony in
detail.
7. Realism: Is the story plausible,
realistic, logical?
8. Cognitive operations. Should be less
in true story: It shouldn’t be necessary
to make inferences: “He appeared
nervous.”
The RM method usually
involves 2+ raters scoring tape.
 Inter-rater reliability should be and
is found by research to be high.
Good as CBCA, anyway.
 Vrij thinks it’s easier to learn and
teach, because…
 There are fewer criteria which are
more concrete and thus less
subject to interpretation.
Vrij’s review of RM research in
Appendix 9.1 has limitations:
 Not all reviewed studies are peer-
reviewed publications.
 Not all studies are given!
 Scoring not standardized.
 Some listings lack inter-rater data.
 Only recent events are studied.
 RM is problematic in children.
 Etc, etc. maybe not important ….
...because:
 Appendix 9.1 shows a mostly
mixed pattern.
 Average accuracy is 68.8 %
overall, which mean many false
alarms (about 29% in truth
tellers) and misses (about 34% in
liars). I.e., group but not individual
results.Yes, RM beats flipping a
coin, but not by much. More work
is needed. (Physiology wins.)
End of RM
“SCAN”
Israeli tool:
Vrij: Widely used, though
Not much researched, nor
endorsed by researchers.
Basic assumption:
 A memory based on actual
experience will differ in content
and “quality” (?) from an invented
or fantasized memory. (Duhhhh!)
 Also problematic: Not all lies are
invented out of whole cloth. Some
are substituted actual memory, as
in most alibis.
Proceedure:
 Suspect writes in handwriting a
statement of events in absence of
investigator (to avoid
contamination).
 Statement is then scored on
several criteria:
The Criteria (+ = seen in truth
tellers. V means vs. CBCA)
1. Direct denials +
2. Specific identifications +
3. Cross-outs(against instructs.) – V
4. Vague memories – V
5. 20-50-30 structure +
6. Emotions +
7. Subj/obj time correspondence +
More….
8. Events in chronological order +
9. Missing info: :”A bit later..” 10. 1st person, present tense +
11. Pronouns “I” Ownership. +
12. Change in language(???):
Change from “conversation” to
“Discussion.” - if not justified. Too
subjective (imho)
Research results with SCAN:
1. Field study: .77 TTs, .88 Liars at
best with Denial criterion.
….But, as with almost all field
studies, no ground truth!!!!! So,
fuggedaboudid!
2. Lab Study(So no ground truth
issue): Three crirteria utterly
failed to discriminate liars and
truth tellers!! So, fuggedaboudid!
Final field study…
 Again no ground truth!!
 Though they claim75% TT
accuracy, 80% liar accuracy.
 Great lack of consistency among
SCAN users: So, fuggedaboudid!
 Bottom SCAN line: Little empirical
support, little standardization.
 Thus the widespread use is stupid.
Based for openers
on Polygraph.
Polygraph:
 Does not mean “lie detector.”
 Means a machine with many
(poly) channels of visually
presented (graphical) information;
in inked paper or laptop display
format.
 A Polygraph machine can be and
is used in many fields of
Psychophysiology
2 Major Protocols currently
used :
 Comparison (“Control”) Question Test
(CQT)-- beloved by enforcers, ‘cuz it’s
easy to use (“Didja do it?”) and tends to
elicit confessions—but hated by
academics who prefer the
 Guilty Knowledge Test (GKT better
known as the Concealed Information
Test (CIT), since knowledge can’t be
guilty (just perps.)
 Both utilize autonomic arousal.
Why do us professors frown on
CQT?
 Pre-test interview cannot be
standardized.
 It compares arousal responses to
relevants. & “controls.”There can
never be true comparison control
questions in the scientific sense
of control.(Yet there could be
better versions.)
 High false positive rate (which CIA
et al. don’t care about….)
Why do we love CIT?
 It compares arousal (?) responses to critical
(probe) and non-critical (irrelevant) stimuli.
 There are usually 6 or more multiple choice
questions with 1 + 5 choices per question.
(Throw away 1st.) Thus for each item, the
P(chance hit) = 1/5=.2
 For 6 INDEPENDENT items, probability of
subject hitting on all 6 by chance =P = .2^6 =
.2 x .2 x .2 x .2 x .2 x .2. Use Bernoulli for
chance hits on < 6. Thus you can reduce the
false positive P as low as you like by adding
independent items (not always so easy).
……and bootstrapping
…..from 4 sites on the scalp:
the class to the
movie…called, “ERP
Averaging”
Since averages are so much
cleaner than single sweeps,
…and show the true stimulus-evoked
event that is time-locked to the
eliciting event, and are more noise free,
….it obviously makes sense to compare
averages rather than single sweeps,
that is, to do analysis, like t-tests on
averages.
People did that in comparing group
ERPs or grand averages.
For example,
 The schizophrenic group average
versus the normal average
 or the well-trained group average
P300 vs. that of the untrained
group.
 Remember, in a group, each
subject has an average ERP.
 ….but within a single subject,
there are only single sweeps to
compare
In Bootsrapping…
 …..the original set of single
sweeps is repeatedly randomly
sampled –but with replacement—
…yielding multiple averages in a
single subject.
 Let’s say there are 6 repetitions of
sampling of 18 single sweeps:
….that look like real average of
original set but with variations
Correlation Example
Let's assume that we want to look at the relationship between two variables
Person
Height
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
68
71
62
75
58
60
67
68
71
69
68
67
63
62
60
63
65
67
63
Self
Esteem
4.1
4.6
3.8
4.4
3.2
3.1
3.8
4.1
4.3
3.7
3.5
3.2
3.7
3.3
3.4
4.0
4.1
3.8
3.4
Now we're ready to compute the correlation value. The formula for the correlation is:
Remember 3ST protocol:
 Probe (P) is the guilty item (stolen item)
 Irrelevants (Ir) are non-stolen items
 Target (T)is a IR with unique response
How P300 amplitude is
supposed to catch Liars:
1)P>I (‘BAD’)
2)P-TR corr
>P-I corr(‘BC-AD’)
1)P=I
2)P-I corr
>P-TR corr