On this page:
Mehrabian's 7%-38%-55% "rule"
Someone recently (at the time of writing) posted the following URL to an online discussion group I belong to:
It is an article, originally published in Transitions, Vol. 7, No. 2, November 1999. pp.11-14, called Let's Dump the 55%, 38%, 7% Rule, written by one Herb Oestreich.
"Herbert Oestreich, Ph.D
So if someone with a set of qualifications like this behind him sees fit to attack this cherished statistic then shouldn't we sit up and take notice?
Professor Oestreich does us a favour by raising the question, but his accusations don't actually hold very much water For example, according to Oestreich (referring to Professor Albert Mehrabian):
"After careful reading of his books and articles, I find that he does not caution the reader adequately of the limited application of his study results. He does not properly emphasize that the disproportionate influence of tone of voice and body language enters the situation only when there is ambiguity in the communication, when the words are inconsistent with the tone of voice or body language of the speaker."
Which might be fair comment except that the title of Mehrabian's first article says precisely what Oestreich is complaining it doesn't say.. The full reference for the article being- and this is taken directly from the References section at the back of Oestreich's own article:
Mehrabian, Albert, and Wiener, Morton. "Decoding of Inconsistent Communications," Journal of Personality and Social Psychology, Vol. 6, No. 1, May 1967, pp. 109-114
Likewise Chapter 5 of Mehrabian's book Silent Messages, where the "7%-38%-55% Rule" is introduced, has the following sub headings:
If there's a way of stating more clearly that the research relates specifically to inconsistent communications I must confess I can't imagine what it might be.
"Mehrabian comments as follows: 'Generalizing, we can say that a person's nonverbal behavior has more bearing than his words on communicating feelings or attitudes to others.' In my opinion, that is an overstatement. It does not contain a much needed qualification of that conclusion."
What Oestreich fails to mention are Mehrabian's qualifications in other parts of the text, such as:
"Incidentally, we should be careful to note that these assertions about the disproportionate contribution of implicit, relative to verbal, cues is limited to feelings (pleasure, arousal, dominance) and like-dislike. Obviously implicit expressions are not always more important than words. In fact implicit cues are ineffective for communicating most referents denoted by words (for example, 'I'll see you tomorrow afternoon at 2:00 p.m.,', 'I was wearing my new velour suit yesterday,' or 'x + y = z').."
"In a comprehensive study of inconsistent messages of pleasure-displeasure and dominance-submissiveness in vocal and visual (face and/or body) cues, it was established that visual cues were more powerful than vocal cues in determining the overall effect inferred from moderately inconsistent messages. This effect was greater when the visual cues involved the face. However, in the case of extreme inconsistency, visual cues were weighted less than vocal cues. The latter reversal was interpreted by noting that subjects are less likely to believe and rely upon visual cues (which are easier to control) when visual and vocal cues are extremely discrepant, thus implying deception."
In fact, Mehrabian does explain in his book that:
In short, whatever we may think of Mehrabian's experimental design, it seems at odds with the evidence to claim that he did not adequately qualify his conclusions.
Educational Seduction, or "The Dr Fox Effect"
Dr Myron L. Fox was a truly remarkable man, not least because he managed to pack so much into such a short life.
In 1973, Dr Myron L. Fox (a psychiatrist) delivered his lecture on Mathematical Game Theory as Applied to Physical Education to three separate audiences (55 people in all) composed of educators, school administrators, psychiatrists, psychologists and social workers. Each one hour lecture was followed by a 30 minute question and answer session.
Which is quite interesting, when you think about it, because "Dr Myron Fox" never studied psychiatry in his life, and he certainly didn't have a doctorate in the subject. On the contrary, he was an actor, trained for the task by the three men who wrote the lecture and set up the presentations:
"And so what?" you might ask. "If the script was written by well-qualified experts in the field, is it really important who delivers it?"
It seems not!
For full details see: Naftulin, D. H., Ware J.E., Jr. and Donnelly, F.A. "The Doctor Fox Lecture: A paradigm of educational seduction," Journal of Medical Education, 1973, No. 48. pp.630-35.
It is worth pointing out that the Myron Fox experiment was certainly not a "one off" event.
Although the proportion of valid content did play a part in determining the test scores, in all three cases, the students who were shown the "seductive" version of a lecture gave it a noticeably higher average score than that awarded by students who viewed the "unseductive" version of the same lecture.
The 7%-38%-55% Rule in a "Real Life" Scenario
In a later, but less formal, variation of the Fox experiment (this time using meaningful content), Professor Ceci, an established teacher of Developmental Psychology at Cornell University, delivered two versions of the same course over two consecutive terms (semesters).
In Professor Ceci's view, the only significant difference between the two courses was that, in the spring term, he made deliberate use of voice tone and gestures to make his presentations more varied and interesting.
Although there was no significant difference between the two groups, although they used the same textbook, and although their test scores were compatible, the students who attended the spring course rated everything about the course more highly, even the textbook. In relation to how much they believed they had learnt, for example, out of maximum of 5.0 points, the autumn students gave an average of 2.93, which jumped to 4.05 in the spring term.
In the US, where collecting student rating of their teachers has become a widespread practice, to get these higher ratings is a worthwhile result in its own right. And even where that is not a consideration, surely it is desireable that students actually appreciate their courses rather than simply seeing them as barriers to be overcome?
Just A Moment!
The last piece of research relevant to the validity, or otherwise, of Mehrabian's "7%-38%-55% Rule" is provided by Professor Robert Rosenthal, a professor of social psychology at Harvard University and co-author of the famous study of the effect of teachers' expectations: Pygmalion in the Classroom (1968).
Rosenthal has run numerous tests of how accurately we can assess each other's basic attitudes on the basis of minimal evidence. In particular, Rosenthal has compared students' ratings of instructors on the basis of three "thin slices" with the ratings given to those same instructors by their students after a complete term/semester.
After viewing three "thin slice" (very short) video clips - from the beginning, middle and end of a class - of just 10 seconds duration each, students gave the instructors grades that closely matched the average ratings the instructors got from their own students at the end of the semester on qualities such as confidence, energy and warmth (the match was as high as 80%).
In a related set of experiments Rosenthal had audio tapes of lectures electronically "doctored" so that it was possible to hear the speaker's vocal characteristics - tone, tempo, etc. - but not the actual words they were saying.
A DIY Vocal Characteristics Experiment
For a live demonstration of how powerful emphasis alone can be in a verbal message, you might like to try this simple experiment:
Here is a simple seven word message:
I didn't say he stole the money
The Eyes (and Ears) Have It
So, what can we conclude from all of this evidence?
Clearly there are variations in intent and design between the various experiments. Nevertheless, there does seem to be a consistent message throughout which, contrary to Professor Oestreich's claim, suggests that Mehrabian actually understated his case when he said that we tend to attach more weight to vocal qualities and body language associated with a message than we do to the straightforward "meaning" of the words themselves.
So maybe we do need to re-examine the way we sometimes treat the "7% - 38% - 55% Rule" as though it were set in concrete. And we certainly need to stop assuming that it applies to every message, regardless of context. And what we equally need to retain is our awareness that the meaning of our messages resides both in the words, and in every facet of the manner in which we deliver those words.