Six hats for software testers - White

This tip comes from Julian Harty, and is based on the work of Edward de Bono. Julian uses the metaphor of six thinking hat to provide six different and distinct viewpoints for software testers. When you wear your white hat, you focus on the facts. What facts do you need? How can you get those facts?

White represents a sheet of paper, perhaps a computer printout. The white hat is about information. The information can range from hard facts and figures to things we believe but don’t yet know. The information may include stating second-hand facts e.g. “The CEO of our competition claims their product can sort widgets by color and texture”, or stating other people’s beliefs or feelings e.g. “Jack is angry with the project team and blames the testers for holding up the launch”. Sometimes the information may be contradictory, if so we record everything, and only decide later, if and when we need to make a choice.

The white hat is neutral, and reports on the world as we find it. With the white hats we ask questions such as:
• What information do we have?
• What information do we need?
• What information is missing and what questions do we need to ask to get the information we need?

We should question ‘facts’ because beliefs and opinions may masquerade as facts unless they are challenged and double-checked. Using the white hat we try to qualify facts to determine our degree of confidence in the information presented. For instance we may use a scale of: Certain, Fairly confident, 50/50, Uncertain, No chance! – pick a scale to suit your project and circumstances.

You can see Julian present the topic at STARWEST here.
HeuristicsMichael Kelly