As for supply chain management, Japanese retailers have refined their supply chain operations and developed close marketing ties to their customers, according to, Wharton operations and information management professor. He points to Seven Eleven, the Japanese company that owns 7-Eleven stores in the United States and in Japan. Fisher says the company is highly regarded as an innovative retailer in Japan where, for example, 7-Eleven has focused on improving its tuna supply chain to appeal to Japan's discriminating sushi buyers. The chain, among other things, carefully analyzes consumer preferences in tuna, such as color and freshness. "They have really made a science of it. They have figured out how to slow down the rate the tuna changes color to slow down the aging process of the tuna — at least as it is perceived by the customer."