Alex Pentland - Honest Signals

How They Shape Our World

ALEX (SANDY) PENTLAND
with
TRACY HEIBECK

A Bradford Book
The MIT Press
Cambridge, Massachusetts
London, England

2008 Massachusetts Institute of Technology

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Library of Congress Cataloging-in-Publication Data

Pentland, Alex (Sandy).

Honest signals : how they shape our world / Alex (Sandy) Pentland.

p. cm.

Includes bibliographical references and index.

ISBN 978-0-262-16256-2 (hardcover : alk. paper)

1. Social perception. 2. Organizational behavior. 3. Business networks.

4. Social interaction. I. Title.

HM1041.P464 2008

302.12dc22

2008013832

10 9 8 7 6 5 4 3 2 1

d_r0

The group of rising-star business executives gathered at MIT for an important task: each executive would present a business plan to the group, and then the group would choose the best ideas to recommend to a team of venture finance experts. It was a great opportunity. The skills they each requiredthe ability to clearly formulate ideas, effectively communicate to a group of peers, and then persuade others to pursue those ideasare indispensable in business as well as everyday life. These executives had each spent more than a decade building their strengths.

Not only the other group members were watching and evaluating the business plan pitches, however. A sensitive, specially designed digital device was also monitoring each presentation. This devicewell call it a sociometerwasnt recording what each person said in their presentation but rather how they said it.physically? How many back-and-forth gestures such as smiles and head nods occurred between the presenter and the listeners? This device was measuring another channel of communication that works without spoken language: our social sense.

At the end of the meeting, the group selected the ideas that they agreed would sell the best. At least that is what they thought. When the venture finance experts were given the plans to evaluatethis time on paper, rather than via a live presentationthere was little similarity between the two groups judgments. Each group had a different opinion of which business plans were most likely to succeed. Why?

Our up-and-coming executives didnt pick different business plans simply because they werent as seasoned as the venture finance experts. Remember our other observer in the roomthe sociometer? As it turns out, the sociometer was able to predict which business plans the executives would choose with nearly perfect accuracy. Both the sociometer and our executives (even though they didnt know it at the time) were busy measuring the social content of the presentations, quite apart from the spoken, informational part. And which channel of communicationsocial or spokeninformed more of their final decision? Yes, the social channel.

The executives thought they were evaluating the plans based on rational measures, such as: How original is this idea? How does it fit the current market? How well developed is this plan? While listening to the pitches, though, another part of their brain was registering other crucial information, such as: How much does this person believe in this idea? How confident are they when speaking? How determined are they to make this work? And the second set of informationinformation that the business executives didnt even know they were assessingis what influenced their choice of business plans to the greatest degree.

When the venture finance experts saw the business plans, however, this social channel of communication was purposely removed. They saw the plans written on paper onlywith no live presentation. With the social sense disconnected from the decision, the venture finance experts had to evaluate the plans based on rational measures alone. Unfortunately for them, research has shown that investments made without that personal connection are far more likely to fail. This is why venture capital firms normally only invest in companies they can visit regularly in person, and why many investors pay more attention to the face-to-face interaction among the companys founders than they do to the business plan itself.

This study, along with many others, leads us to a surprising yet illuminating conclusion: people have a second channel of communication that revolves not around words but around social relations. This social channel profoundly influences major decisions in our lives even though we are largely unaware of it. This idea lies at the heart of this book. My goal is to show you how powerful and pervasive this form of communication is in our daily lives, how it changes the way we think of ourselves and our organizations, and how you can make use of this information to better manage your life.

Honest Signals comes from a new and emerging science, called network science, that tries to understand people in the context of their

For the first time, we can precisely map the behavior of large numbers of people as they go about their normal lives. By using cell phones and electronic badges with integrated sensors, my students and I have observed hundreds of participants for periods of up to a year. In the process we amassed hundreds of thousands of hours of detailed, quantitative data about natural, day-to-day human behaviorfar more data of these kind than have ever been available before.

A new measurement tool such as this often brings with it a new understanding of what you are measuring. What we have found is that many types of human behavior can be reliably predicted from biologically based honest signaling behaviors. These ancient primate signaling mechanisms, such as the amount of synchrony, mimicry, activity, and emphasis, form an unconscious channel of communication between peoplea channel almost unexplored except in other apes.

These social signals are not just a back channel or complement to our conscious language; they form a separate communication network that powerfully influences our behavior. In fact, these

We have shown that peoples behavior is much more a function of their social network than anyone has previously imagined. Humans are truly social animals, where individuals are best likened to musicians in a jazz quartet, forming a web of unconscious reactions tuned to exactly complement the others in the group. What the sociometer data demonstrate is that this immersion of self in the surrounding social network is the typical human condition, rather than being isolated examples found in exceptional circumstances.

Why does this ancient communication channel exist? What does it do? Data from biology show that honest signals evolved to co-ordinate behavior between competing groups of individuals.

For instance, honest signals form a communication channel that helps to create family groups and hunting teams. The social circuits formed by the back-and-forth pattern of signaling between people shapes much of our behavior, as our ancient reflexes for unconscious, social coordination work to fuse us together into a co-ordinated (but often contentious) whole.