Log in

The thinking behind a messy graph - Complexity research [entries|archive|friends|userinfo]
The science of complexity and related research

[ website | A science at 30 ]
[ userinfo | livejournal userinfo ]
[ archive | journal archive ]

The thinking behind a messy graph [Apr. 28th, 2010|03:22 pm]
The science of complexity and related research


A new york times article on the use and misuse of powerpoint has gotten some attention recently. The picture below was presented as a horrifying example of how bad powerpoint graphics could be.

As the NY Times put it: "A PowerPoint diagram meant to portray the complexity of American strategy in Afghanistan certainly succeeded in that aim."

While we can agree that something like this shouldn't be presented on a powerpoint slide, it's not a typical example of bad powerpoint. Nothing like the awful powerpoint that was partially to blame for the space shuttle columbia disaster. There's not even a bullet point here.
But if you click on the image and examine it in detail, notice what the arrows try to convey and especially the green boxes to the right.
You'll notice, this is actually a system dynamics diagram! This gives an interesting insight into the thinking of the US military.

Those of you familar with system dynamics will recognize feedback loops here, some of which seem straightforward. A high insurgent capacity and effectiveness increases their experience, training and leadership which in turn increases their capacity, but with a time delay. A longer loop imply that the more territory not under allied control, the bigger the power of the insurgents.

But as you examine each arrow "A -> B" you notice that every arrow implies "A increases B". So every feedback loop in this diagram is a positive feedback. In system dynamics, we know that most systems tend to have both positive feedbacks and negative, goal-seeking or self-limiting loops. This is strangely absent from this military analysis.

We know that if there are only positive feedback loops in a system, then it will tend to extremes. Either things grow into the sky or they end in catastrophy. Either the allies will score a decisive victory against the insurgents or the insurgents will overrun Afghanistan. Couldn't it be that the war will drag on? That there will be no victory or defeat but that the insurgents will continue to be a force to be reckoned with in Afghanistan for decades? No. In this diagram, a stalemate is impossible. That the war does not end, is literally unthinkable in this model.

So perhaps this diagram, while messy in display and badly lacking in system dynamics principles, still reveals something important about the thinking in the US military.

[User Picture]From: taziarm
2010-05-04 05:04 am (UTC)
I am very happy you posted this. While my friends were making fun of this graph, I was feeling the same way. It's not the complexity of the graph that's the trouble. It's that this graph is modeling poorly with very serious outcomes. My hope is that negative feedback loops, reinforcing and balancing were built into the model in reality and that this graphic that's going around was an earlier, or not fully specified, model. Indeed if this was modeled on a computer, clearly the outcomes it produced would be absurd. The solution however would be to refine the model, not abandon it as it has been suggested. Either way, thank you for posting.
(Reply) (Thread)