This text highlights statistical methods useful for the behavioural sciences from a practitioner's perspective. The format and presentation of statistics should encourage students to research and analyze data. Students are exposed to the power and time-saving features of computer software with examples of output from Minitab, SPSS, BMDP, SAS, and others. Examples and exercises use real data to motivate students and show them the importance of statistical techniques in behavioural research. The edition has been improved by increasing computer coverage and integration, including graphical representations of computer output. Sections on probability, chi-square and multiple regression have been revised for greater clarity.