17.   Is it Time to Dump the "7%-38%-55% Rule"?



On this page:

Mehrabian's 7%-38%-55% "rule"

"Dr" Myron L. Fox

Professor Ceci's Experiment

Rosenthal's "Thin Slices"

A DIY Experiment

The Eyes (and Ears) Have It

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:

http://www.cob.sjsu.edu/oestreich_h/Communic%20 Article.doc

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.
Who is Herb Oestreich?
This is just a brief clip from his resume on the San Jose State University website:

"Herbert Oestreich, Ph.D
Presently Professor Emeritus, College of Business, San Jose State University. More than 25 years experience teaching graduate and undergraduate courses in Human Resource Management, Conflict Management and Negotiation, Labor Relations, Labor Law, Compensation Management, Supervision, Fundamentals of Management and other topics."

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?
Well, yes and no.

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:

  • Resolution of Inconsistent Messages (p.75)
  • General Function of Inconsistent Messages (p.80)
  • Inconsistent Messages and Social Influence (p.83)
  • Inconsistent Messages and Psychological Disturbance (p.85)

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.
Anyway, Professor Oestreich doesn't stop there.  He goes on to comment on a passage in Silent Messages:

"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').."
page 79.

and this:

"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."
page 77.   Italics added.

In fact, Mehrabian does explain in his book that:

  • The "7%-38%-55%" findings only apply to communications where the messages communicated via the three channels (words/vocal signals/body language) are not consistent with each other
  • The research applies to communications about "intangible" subjects such as the speaker's feelings - not where the message is purely factual (for example, "I'm worried about missing my train" as compared with "There is a train for London at 10:30am")
  • If there is too much inconsistency between the messages then we tend to adopt a different weighting system

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.
With all due deference to Professor Oestreich, I believe he is basing his rejection of Mehrabian's findings on a very selective review of the literature.  And I'm referring here not only to Mehrabian's research, but also to related evidence in the work of Dr Robert "Pygmalion in the Classroom" Rosenthal, not to mention the fascinating case of Dr Myron Fox.

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.
According to the "happy sheets" filled in (anonymously) after each session, nearly 80% of the attendees rated Dr Fox "an outstanding psychiatrist", and agreed that "he used enough examples to clarify the material", that "the material was well organised", and that the lecture "stimulated their thinking".  Whilst the remaining delegates weren't quite as fulsome in their praise, no one actually criticised Dr Fox or his presentation, nor did anyone question his authenticity.

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:

  • Dr Donald H. Naftulin, associate professor and director of the Division of Continuing Education in Psychiatry, University of Southern California School of Medicine
  • John E. Ware, Jnr., assistant professor of medical education and health care planning, and Director of Research and Evaluation at the Southern Illinois University School of Medicine, and
  • Frank A. Donnelly, Instructor in psychiatry (psychology) in the Division of Continuing Education in Psychiatry at the University of Southern California

"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?"
Well, supposing I tell you that the lecture itself was concocted by stringing together bits and pieces from an article published in Scientific American, with non sequiters, neologisms, contradictory statements, jokes and meaningless references to unrelated topics.  In short, the bogus professor was armed only with some brief training in the relevant jargon and an essentially meaningless script bearing a nonsense title.  Does "Myron Fox's" lack of formal education still not matter?

It seems not!
"Myron Fox's" presentation skills (authoritative vocal and body language), backed up by an impressive but totally fictitious CV, were apparently enough to blind his audiences to the nonsensical verbal content of his lecture and his 'off the cuff' responses during the subsequent Q&A session.

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.
(The full text of the article can be found at http://www.er.uqam.ca/nobel/r30034/PSY4180/Pages/Naftulin.html, courtesy of Professer Jean Bélanger of the University of Quebec.)

It is worth pointing out that the Myron Fox experiment was certainly not a "one off" event.
In the following year, at the 13th Annual Conference on Research in Medical Education, in Chicago, Professor Ware and another researcher used the same actor to create a series of videotaped lectures on "The Biochemistry of Memory".  There were three versions of the lecture with high, medium and low value content, the low-content being little more than a set of descriptions of experiments but without the results, plus unrelated material, and circular arguments involving unimportant and/or meaningless thoughts.  Each version of the lecture was delivered once in a monotonous "unseductive" manner, and once in a "seductive" manner where the actor/presenter made use of expressive gestures and facial expressions, humour, enthusiasm, etc.  The attendees were then asked to rate the lecturer and carry out a short test of their subject knowledge.

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 the autumn (fall) term Ceci delivered the course in his normal style, giving little attention to his style of presentation.  Over the Christmas break he took a brief course in presentation skills from a professional media consultant, and made use of his new skills when presenting the same course in the spring term.  (Similarity of course content was achieved by recording the classes during the autumn term as a reference point during the spring term).

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.
And it worked.
(The other possible factor might be the weather and the onset of SAD conditions during the autumn term, which would tend to scale down as the spring term progressed.  The results, however, must be viewed in the context of numerous related experiments which have shown similar progress in circumstances which would not be influenced in this way.)

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%).
Even more remarkably, the students were almost as as accurate in their ratings when the length of the three video "slices" was reduced to just 2 seconds each.

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.
Once again, even on the basis of just a few seconds playback, students were able to predict an instructor's end of semester ratings with a high degree of accuracy.

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

  • Read the message out loud. seven times, each time putting the emphasis on a different word, thus
    I didn't say he stole her money
    I didn't say he stole her money
    I didn't say he stole her money
    I didn't say he stole her money
    I didn't say he stole her money
    I didn't say he stole her money
    I didn't say he stole her money
  • Notice how much difference there is in the meaning of the sentence as you change the emphasis on just one word.  (And does the emphasis you put on that word mean you have to change the way you say the whole sentence?)
  • Notice how you feel as you speak each message.


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.
And is this really so surprising?  After all, few words have a single, unambiguous meaning, and we so often say what we think we ought to say, or what we think the other person wants to hear, etc., rather than simply saying what we are really thinking.

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.
To borrow the catchphrase of a well-known Irish comedian, it really is "the way you tell 'em" that counts.