NEW YORK (AP) - Twitter has named Marjorie Scardino as a director, adding a woman to the all-white male board for which it's been sharply criticized. Scardino, 66, was the CEO of Pearson PLC, a publishing and education company, from 1997 to 2012, Twitter Inc. said in a regulatory filing on Thursday. Before that, she worked at The Economist Group, publisher of The Economist and CQ Roll Call. Her roles at the company included CEO. Twitter tweeted the news of Scardino's appointment from its official account. Twitter, like Facebook before its own IPO, was criticized for not having women or minorities on its board of directors. Facebook named its chief operating officer, Sheryl Sandberg, to its board after it went public in May 2012. Unlike Facebook, though, Twitter still doesn't have any high-ranking female executives. Scardino joins CEO Dick Costolo, Chairman Jack Dorsey, along with co-founder Evan Williams and venture capitalists such as Peter Fenton, a general partner at Benchmark Capital, on Twitter's board. Faced with criticism about its lack of board diversity - three of Twitter's directors are named Peter - Costolo tweeted earlier this year that diversifying the board "has to be about more than checking a box." As head of Pearson, Scardino was the first woman to become CEO of a FTSE 100 company 16 years ago. The index of leading British stocks is similar to the S&P 500 in the U.S. In her words, not much has changed in that time when it comes to gender imbalance. Last year, she told the U.K. 's Telegraph that she "thought in 1997 that by the time I left Pearson things would be different in terms of how many women there were as chief executives or chairmen or board members. It's not too different and for that I'm sorry.