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UDO UNDEUTSCH*
The actual use of investigative
physiopsychological examinations
in Germany
EUROPEAN
POLYGRAPH
Volume13•2019•Number2(48)
TuvyaT.Amsel*
TelAviv
Israel
AnUrbanLegendCalled:
“The7/38/55RatioRule”
Городская легенда: “The 7/38/55 Ratio Rule”
Key words: nonverbal communication, spoken word, tone of voice, body language
We have all experienced, consciously or subconsciously, that the spoken words are but
one element of the conveyed message. Along with the words we notice the intonation
of the voice, the rhythm and speed, the speaker’s expressions and body language. Many
times, the non-verbal cues and signs carry agreater in uence on the listener than the
spoken word.
e impact of each channel (spoken word, tone of voice and body language) on the
listener is what UCLA psychology professor Albert Mehrabian researched. In 1967
Mehrabian published his experiments results in two papers. [1] Mehrabian determine
the weight listeners place on each of these elements: 7% on verbal, 38% on vocal and
55% on facial. Shortly a er publication, Mehrabian conclusions caught the eyes of the
public, in where it was popularly coined as the 7/38/55 ratio.
DOI: 10.2478/ep-2019-0007
© year of fi rst publica on Author(s). This is an open access ar cle distributed under
the Crea ve Commons A ribu on-NonCommercial-NoDerivs license h p://crea vecommons.Org/licenses/by-nc-nd/3.0/
* ta@amsel.co.il
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TUVYAT.AMSEL96
Apparently, what caught the public eyes were the gures, the numbers, the percentage.
Psychology does not consider to be an exact science, and not surprisingly so. A er all
psychology’s forth father was philosophy. Psychology seems to research the empirical
approach to questions raised by philosophy, and as such its’ conclusions considered to
be abit ambiguous and vague. Yet, here comes apsychology paper that de nes its’ con-
clusions in exact gures. And numbers and percentage carry the image and façade of
mathematics i.e. exact and accurate and in return reliable. So, no wonder that in no time
consultants, experts and alike, in various elds which involve inter -personal commu-
nication started to quote Mehrabian’s formula. is, in spite the fact that Mehrabian’s
formula was misrepresented by them!
Yet, as Mark Twain’s famous phrase goes “alie can get halfway around the world before
the truth can get its boots on”, Mehrabian’s 7/38/55 formula became arule. Arule that
shortly was referred to as an axiom.
Eventually, investigators too adopted the formula for credibility assessment of crimi-
nal suspects’ statements. Take as an example the o en-quoted Christopher Voss who
served for 24 years in the FBI as “… lead international kidnapping negotiator … lead
Crisis Negotiator for the New York City Division of the FBI… New York City Joint
Terrorist Task Force for 14 years”. [2] In his June 2016 blog titled “3 Insider Keys to
“How to Spot ALiar”, Voss shares with readers his expertise: “…the second thing Igo
into is the 7:38:55 ratio. e hypothesis here is that amessage is carried at arelative
weight of 7% content, 38% delivery, and 55% body language. Regardless of what you
think of this speci c ratio – body language is agreat source of information about your
counterpart’s veracity”.[3]
If we will follow Voss’s 7/38/55 ratio advise we may face the following scenario: Asus-
pect in ahomicide case is being questioned by the police. e suspect is anormative
law obedience citizen, who in aspore of amoment in amiddle of aheated argument,
lost his temper and killed his neighbor. Terri ed of what he just did he ed the scene of
crime. When rst questioned by the police he denied any knowledge let alone involve-
ment in the crime. Weeks later a er an in-depth police investigation he was called in
again for an interview. By now he is full of remorse, self-blaming and sorrow of what he
did. A er aprolonged interrogation he is willing to confess. e investigator asks him
again for the hundredth time: “Have you killed Joe?” While getting ready to admit,
the suspect experience an inner dilemma, in one hand he is ready to confess while on
the other hand he fears the consequences that will follow: the trail, the publicity that
will a ect and shame him and his family, the punishment. And so, when he answers to
the question by saying: “Yes, Idid”, his voice is hesitant and his inner con ict is being
re ected in his body language: he moves on his seat uncomfortably, avoid the investiga-
tor eye contact, cover his face, etc. e trained investigator picks up all these signs and
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ANURBANLEGENDCALLED:“THE7/38/55RATIORULE” 97
cues. Being agreat believer in the 7/38/55 rule he reaches the conclusion that he has
just received afalse confession. A er all the spoken words (7%) contradicted the vocal
tone (38%) and the suspect’s body language (55%). Bottom line 93% of the conveyed
message contradict the spoken word which point in the direction that the suspect is
lying thus, his confession is false.
If the investigator’s decision to overlook the confession seems irrational and illogical,
note that actually the originator of the 7/38/55 ratio rule, prof. Mehrabian himself will
object and disagree with the investigator’s conclusion, or in his own words: “… My nd-
ings … have received considerable attention in the literature and in the popular media…
Please note that this and other equations regarding relative importance of verbal and
nonverbal messages were derived from experiments dealing with communications of
feelings and attitudes (i.e., like-dislike). Unless acommunicator is talking about their
feelings or attitudes, these equations are not applicable.“[4]
But at this time, regardless of Mehrabian explanations the formula gained so much
popularity that Mehrabian warning and clari cations passed unnoticed.
MehrabianStudies
e studies focused on decoding the relative impact of facial expressions, vocal tone
and spoken words. Both studies dealt with the manner individuals communicate emo-
tions (negative or positive) as being expressed and displayed in asingle emotional bear-
ing word.
In the rst study Mehrabian and Wiener [5] investigated which of these two factors:
spoken word and the intonation and the tone of that spoken word has agreater impact
on the listener when that spoken word is inconsistent with the tone of voice. 30 partici-
pants, divided to 3 groups (@10), were asked to listen to the recordings of two women
who read nine di erent words (three positive “dear”, ”thanks”, and “honey”, three neu-
tral “maybe”, “oh”, and “really “and three negative “brute”, “don’t”, and “terrible”). e
women spoke in three di erent tones (positive, neutral and negative). e participants
were instructed to rate the degree of positive attitude of the women, subject to the fol-
lowing instructions: paying attention only the content, only the tone of voice and to all
the available information. e experiment results were that the participants were better
in detecting emotions in the tone than in the spoken word.
Mehrabian second study carried out with Ferris,[6] investigated which of these two
factors: tone of voice and facial expression has a greater impact on the listener. e
participants were listening to arecording of three women repeating the single word
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TUVYAT.AMSEL98
“maybe” in three di erent expressing tones: like, neutral, and dislike. Later the partici-
pants were presented with female face photos expressing the same three emotions. e
participants were asked to guess the emotions in the recorded voices, in the photos and
both in combination. e experiment results were that the participants were better in
detecting the emotions in the photo than in the recording.
Abirthofaformula
Based on the results of the studies and in spite the fact that the two studies were di er-
ent, the rst compared spoken word to tone and the second tone to facial expression
(spoken word was not part of the second study), Mehrabian integrated the results of
the two into one, suggesting that the combined e ect of each channel is the weighted
sum of their independent e ect with the coe cients of .07 (word), .38 (tone) and .55
(facial expression). It should be noted that in spite of deriving the gures from research,
the formula ratio gures were arbitrary without being supported by astudy i.e. they
were not proven.
In addition to the unsupported formula, the studies received alot of critiques such as:
the situation was arti cial, the participants were aware of the experiment scope, the
experiments structure, the limited amount of talking and much more. But, Mehrabian’s
studies highlighted the focal points of inter-personal communicating feelings and at-
titudes as well as understanding that inconsistency between these channels when com-
muting feelings and attitudes should call for further inquiry by the listener.
Epilogue
e popularity that the formula gained in spite of Mehrabian’s statement that the for-
mula is being misused and misinterpreted, is avaluable lesson about people: If some-
thing serves them right, they won’t be confused by the facts.
e 7/38/55 ratio rule that swamp the inter-personal communication eld and gained
much popularity, turned out to be amisquoted, misused and unsupported analysis
method, shortly an urban legend and myth that should be forgotten and taken out of
circulation. Game Over.
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ANURBANLEGENDCALLED:“THE7/38/55RATIORULE” 99
References
[1] Mehrabian, A., Wiener, M. (1967). Decoding of Inconsistent Communications.
Journal of Personality and Social Psychology. 6 (1), 109–114. Mehrabian, A., Ferris, S.R.
(1967), Inference of Attitudes from Nonverbal Communication in Two Channels.
Journal of Consulting Psychology. 31 (3): 248–252.
[2] https://blackswanltd.com/our-team/chris-voss.
[3] https://blog.blackswanltd.com/the-edge/3-insider-keys-to-how-to-spot-a-liar.
[4] http://www.kaaj.com/psych/smorder.html.
[5] Ibid, Mehrabian, A., Wiener, M. (1967).
[6] Ibid, Mehrabian, A., Ferris, S.R. (1967).
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