Research Methods in Social Relations SELLTIZ, JAHODA, DEUTSCH,COOK In this book Research Methods in Social Relations, we have had two main goals: to bring the book up to date, and to organize it as a one volume text suitable for use in undergraduate courses as well as in introductory graduate courses in research methods in social psychology and sociology. In bringing out this book, we have taken account of new developments in both concepts and methods. For example, since the first edition was written, there have been new formulations of the concepts of validity and reliability of measuring instruments; the discussion of these concepts has taken account of these new formulations. At the same time, new measuring techniques have come into general use–for example, the semantic differential and the Q-sort– and brief explanations of these techniques have been added. In addition, we have, of course, included illustrations from research carried out since the earlier writing. One other feature of the revision should be mentioned: to the illustrations used in the first edition, which were taken largely from the area of intergroup relations and prejudice, we have added examples from research dealing with other social phenomena, in order to make more clear the applicability of the discussion to a whole range of problems of social relations.