In negotiation, being emotionally inconsistent can force concessions from the opponent and give you the upper hand. But, start nice.

In October 1969 the White House signaled to the Soviet Union that “the madman was loose,” as the U.S. military ostentatiously flew bombers packed with thermonuclear weapons near the Soviet border for three consecutive days.

It was part of President Richard M. Nixon’s “Madman” strategy, designed to make the leaders of other countries, particularly the Soviet Union, think that the American President was emotionally unstable and dangerous. Senior U.S. officials portrayed the President as irrational and volatile in conversations with their Soviet counterparts, leasing them to think of Nixon as totally unpredictable. A sudden decision to bring the bombers home reinforced the “madman’s” unpredictable nature and baffled the Soviets. It was a dangerous tactic, designed to manipulate the Soviets. Nonetheless history — or at least the memoirs of Henry A. Kissinger, then Nixon’s national security adviser – suggests that it worked. Kissinger reports that Nixon was convinced that the “madman” strategy had opened the door to the U.S.-Soviet arms-control deals of the early 1970s.

Although many historians have theorised that such inconsistency gives politicians and heads of state the upper hand in dealing with other leaders, whether it would work in the cooler, more analytical world of business has been unclear. Until now.

In “The Advantages of Being Unpredictable: How Emotional Inconsistency Extracts Concessions in Negotiation,” a paper by Marwan Sinaceur, an assistant professor of organizational behavior at the international business school Insead, the pluses and minuses of being unpredictable or emotionally inconsistent in business negotiations are tested. The article was published recently in The Journal of Experimental Social Psychology.

“We found, through three different methods, that, when you alternate between anger and another emotion over time, you are more likely to extract concessions from the recipient than when you express anger consistently,” Sinaceur says.

In other words, blowing hot and cold is an effective negotiation strategy.

“This is a novel finding,” Sinaceur says, “because most of the research on emotional tactics in negotiations had found that, when you expressed anger, you were likely to get ahead or likely to extract concessions from the other because you are perceived as tougher and more likely to walk away. So the counter-intuition of this finding is that, to some extent, by your expressing less anger overall ... you can get more from your recipient than if you were to express anger consistently.

“Importantly, you also are perceived as a nicer person.”

Sinaceur’s findings arose from three different experiments, ranging from face-to-face negotiations to computer-simulated negotiations and scenarios. In every context those who received alternating emotions from negotiating partners – such as their going from positive to negative, then back to positive again – felt less control over the outcome. “This means that, if you express emotional inconsistency to me, I’m going to perceive you as more unpredictable,” Sinaceur says. “As a result I’ll feel less control and uncertain about your next move. By me feeling less control, I’m going to think, ‘Look, I’d better make further concessions, because the counterpart seems to be very unpredictable and, if I want to increase the likelihood of getting the deal and resolve this uncertainty, I have an excuse to give in.' “Usually people don’t like uncertainty, so, when the recipients see that you are behaving in an unpredictable way, they feel that they’re not in control of what is happening in the negotiation.”

Being emotionally inconsistent can force concessions from your opponent and give you the upper hand. However, Sinaceur advises against starting negotiations with an expression of anger.

“There is a difference between expressing anger, then happiness, then anger, then happiness, versus expressing happiness then anger, then happiness, then anger,” he says. “We found that the latter strategy is more effective in making others comply. Overall it is better to start expressing happiness earlier in the negotiation so that you create positive impressions first. Then, but only then, you can express dissatisfaction when the discussion about the issues gets real and tough. Do not shoot too early. Do not start with anger.

“Clearly,” Sinaceur adds, “if you express happiness and positiveness at the beginning of a negotiation, people are going to feel less threatened and, eventually, they’ll disclose more information to you. Start nice, make people trust you first. Make people talk and confide in you before you get tougher. That’s critical.

“Express anger only later in the negotiation,” he advises, “in fact only at the very end of the negotiations. And do so parsimoniously. The less anger you express, the more impactful it will be. If you express anger late and with parsimony, people are more likely to infer that you’re expressing anger because there is a specific issue at hand and you’re not happy about this or that. It’s not because you are a jerk or you are chronically moody, as may be inferred if you were to get angry from the beginning of the negotiation.

“Finally, even when you express anger at the very end, you can do so in a non-aggressive way by not directly accusing or blaming your counterpart,” Sinaceur concludes. “Express your dissatisfaction with the issue at hand, rather than getting angry and humiliating the other person.

“You can even express dissatisfaction with a positive spin.”

Chris Howells is deputy editor of INSEAD Knowledge.

© The New York Times 2013