William F. Kerby, 81, a career newspaperman who held every major position on the news staff of the Wall Street Journal before becoming an executive officer at the Journal’s publisher, Dow Jones & Co. Kerby joined the Journal’s Washington staff in 1933. He was managing editor and then executive editor from 1942 to 1951, helping to develop the front-page news features and other innovations that shaped the modern Wall Street Journal and its growth into a national paper. Kerby was named executive vice president of Dow Jones in 1961, president in 1966 and chairman of the board in 1972. He retired in 1978 but continued to serve on the Board of Directors until Nov. 19, 1980. As president of Dow Jones and as its chairman from 1966 to 1978, he presided over the company’s diversification into community newspapers, overseas publishing, electronic information services and other ventures. In Bethlehem, Pa., on Sunday of cancer.