Bachelor of Science, University Auckland, New Zealand, 1970. Master of Science, University Auckland, New Zealand, 1971. Doctor of Philosophy, Victoria University, Wellington, New Zealand, 1975.
Assistant lecturer University Auckland, 1976—1977. Associate professor National Chiao Tung University, Hsinchu, Taiwan, 1978. Lecturer Massey University, Palmerston North, New Zealand, 1979—1982, senior lecturer New Zealand, 1983—2000, professor New Zealand, since 2001.
Justice of peace Justices of Peace Association Inc., Palmerston North, 1999—2005. Eldership Church Palmerston North, 1979—2005. Member of New Zealand Statistical Association.
Married Ai Ing Ngu, December 29, 1972. Children: Joseph Chang Sheng, Eugene Chang Fu, Serena Siu Ling.