Publishers succeeded in preventing Amazon from lowballing prices, but “unfortunately, it may be that consumers aren’t happy with the higher prices,” said Mike Shatzkin, chief executive of publishing consulting firm Idea Logical Co. Industrywide, for the first five months of 2015, publisher e-book revenue for adult, children’s and young adult titles fell 10.4% to $583 million compared with the same time in 2014, according to the Association of American Publishers’ monthly StatShot report, which collects sales data from 1,200 publishers in the U.S.