How Amex could own both local and travel

Getting enough data to make local recommendations has proved tough. A restaurant reviewer writing for a local newspaper might write a hundred or so reviews a year. Zagat might cover several thousand in its printed books. Yelp provides near universal coverage in the United States, but it still doesn’t have enough information to provide useful recommendations.

But American Express is sitting on top of some of the best data in the world with which to make recommendations: transaction histories of millions of cardholders. I’ve been an American Express cardmember since 1993. In theory, AmEx has 18 years of data on me. (AmEx spokeswoman Charlotte Fuller declined to comment on how far back AmEx keeps transaction data.)