00305nam a2200109 a 450000500170000002000150001708200130003210000210004524500750006626000340014130000200017520251203091611.0  a0745601723  a58868b_  aMarsh, Catherine  aExploring data: an introduction to data analysis for Social scientists  aCambridge: Polity Pressc1988  axx, 385p.c23cm