A Domain Knowledge typically is how you want to analyze your data. Essentially, this is Jane's view point of how to understand Consumer complains against her company. While Signals can generate all the Buzzwords around these complains, it also encourage you to input your own Domain Knowledge through creating Analysis Tabs.
Your practice and domain knowledge is, therefore, represented in a series of Tabs and Visualization Widgets within each tab. To augment your decision making process, the system will follow your interactions to slice and dice your analytics results.