Robust economic growth--3.3% or better, over multiple years--sustains a positive feedback loop.

FORBES: What Grows An Economy?

Traders use multiple markets at once and create a feedback loop.

FORBES: The Truth About the Flash Crash

The foundation and others have estimated that it could cost between 1.5% and 2% of the overall budget for teacher compensation and benefits to implement a feedback and evaluation system based on multiple measures of teaching performance.

CNN: Bill Gates: Invest in better teaching

In his notebook, the Scout must demonstrate an initial concept, multiple design iterations based on initial testing, and feedback from blind testing.

ENGADGET: blogger-avatar

This year, analyst feedback prompted us to apply a revenue multiple of 3.5, in between that of FactSet, the highly profitable financial data firm (approx 5 x sales), and slightly sluggish Thomson Reuters, a direct competitor (just under 2 x sales).

FORBES: How World's Richest Politician Michael Bloomberg Got $5 Billion Richer This Year