The New York Times bestseller list not only measures book sales, it also sells books; millions of readers make selections based on what they find there. Starting early next year, the New York Times Company will try to bring that clout to bear on the electronic books market. The company announced yesterday that it will combine information from booksellers like Amazon with data compiled by a company called RoyaltyShare, which offers content producers tools for tracking market performance and for managing payment systems. RoyaltyShare’s data, the Times avers, will provide a check on the sales figures provided by booksellers like Amazon.com, which is famous for trumpeting sales increases while keeping the actual numbers vague. In this way, Amazon is like the Times, whose methodology for compiling its bestseller lists is a trade secret.