Weapon of Math Deduction: A Statistical Formula for Conflict Evaluation

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IT’S NOT THE SIZE OF THE ARMY; it’s how you use it. That’s the conclusion of a recent study by Patricia Sullivan, a professor at the University of Georgia, who has devised a simple yet effective statistical formula that correctly predicts the outcome of 78% of the conflicts plugged into it.

Pr = probability that an intervening nation will achieve its goals
Limited goals mean better odds. Sullivan calculates the U.S.’s chances of success in Vietnam were 22%. The 1991 Gulf War had a 93% chance of succeeding. The invasion to overthrow Saddam had a 68% chance of working; as for routing insurgents and installing democracy, chances of success are 1 in 5.

x, y = variables
ß = magnitude and direction of variables’ effects
Sullivan’s formula has several variables, including war aims, troop levels, alliances, and length of conflict. She found that as troop levels increase, the probability of successfully achieving political aims through force decreases.


Pr(yi=1|xi) = 1/(1 + exp(-xi ß))


i = intervention in question
Sullivan tracked 122 military interventions involving the U.S., Russia, China, France, and the U.K. between 1945 and 2003. Overthrowing governments is easy, but using military intervention to get nations to do what you want has only a 17% chance of success. Propping up foreign regimes works just 40% of the time.


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SIX TRUTHS

Reclaiming power from those who abuse it often starts with telling the truth. And in "This Is How Authoritarians Get Defeated," MoJo's Monika Bauerlein unpacks six truths to remember during the homestretch of an election where democracy, truth, and decency are on the line.

Truth #1: The chaos is the point.

Truth #2: Team Reality is bigger than it seems.

Truth #3: Facebook owns this.

Truth #4: When we go to work, we're in the fight.

Truth #5: It's about minority rule.

Truth #6: The only thing that can save us is…us.

Please take a moment to see how all these truths add up, because what happens in the weeks and months ahead will reverberate for at least a generation and we better be prepared.

And if you think journalism like Mother Jones'—that calls it like it is, that will never acquiesce to power, that looks where others don't—can help guide us through this historic, high-stakes moment, and you're able to right now, please help us reach our $350,000 goal by October 31 with a donation today. It's all hands on deck for democracy.

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