Observational Data:

Seth Godin’s post offer’s this little nugget:

DATA is observational. What do people actually do? Wal-Mart uses data to decide if an end cap is working. Google Adwords advertisers use data to decide which copy delivers clicks and sales. The library can use data to decide which books to buy (and not to buy). Paco Underhill uses data to turbo charge retail. Data is powerful, overlooked and sometimes mistaken for boring. You don't have to understand the why, you merely need to know the what.

Too often we ignore the wealth of data in the restaurant. Chefs and entrepreneurs are so focused on what they think will work that they ignore what the menu sales data is telling them. Never start a P& L review until you have reviewed what the product sales mix tells you customers are buying. P & L information means nothing until you understand what is selling.