Neville at the warehouse calls Sophie at the factory to tell her that surging demand has almost depleted the company's stock of microchips. Alarmed, Sophie orders piles of raw materials to build more chips. Three months later the warehouse is restocked, but now Neville says demand has fallen off. Sophie immediately stops ordering materials-only to see demand rebound, resulting in a new chip shortage.

Unintentional feedback loops like this are rife in business, and they're hard for managers to tame without knowing which loops cause the most damage and therefore should be tackled first. They're also costly; word of supply chain glitches typically degrades a firm's stock price by 20 percent, according to researchers at the Georgia Institute of Technology. While computer simulations of supply chain fluctuations help, they're hard to interpret or operate collaboratively. Now, with the aid of a tabletop computer interface invented at the MIT Media Laboratory and funding from Intel, researchers at MIT's Sloan School of Management are giving managers a hands-on feeling-literally-for the factors that can mend or upend their supply chains.