Spreadsheet Models for Managers

Session 4
Temporal Response

he focus of this session is the use of arrays to model temporal response of systems. We'll show how to do this using both a high-level method, called convolution, and a more "nitty-gritty" approach using arrays.

Since we use arrays so often, we need to be skillful in manipulating them, including extracting pieces from arrays. In this session, we'll survey Excel's facilities for extracting subarrays from arrays, using worksheet functions and reference operators.

With knowledge of arrays in hand, we're prepared to examine an approach to computing temporal responses of systems to changing inputs. Our approach is based on a method that is routine in physics, statistical analysis, and communications theory — convolution. Convolution is a powerful approach, one that — once learned — enables you to solve complex modeling problems with a single form. Models that use convolution instead of less powerful alternate methods are more easily understood, more reliable, and cheaper to maintain.

Below is a summary of the materials for Session 4.

• Readings
  • Convolution
  • Reference Operators
• Class notes
  • As PowerPoint: 2000-4 or 2007+
  • As Web pages
• Demonstration
  • Narrative
  • Excel Example: 2000-4 or 2007+
• Homework assignment
• Solution to Problem Set 3
  • Narrative
  • Excel Solution: 2000-4 or 2007+