  We propose a design for schedule-based execution trading strategies based on
uncertainty bands. This formulation: 1) simplifies strategy specification and
implementation; 2) provides for flexible allocation among passive,
opportunistic, aggressive, and dark pool crossing execution tactics; 3) allows
for rapid enhancements as new optimization methods, scheduling techniques,
alpha models, and execution tactics are developed; and 4) yields information at
macroscopic (strategic) and microscopic (tactical) levels that is easily
published to trading databases and front-end applications.
