Respectable research studies may be the In concluding this discussion it is important to realize that research may be car- simple descriptive fact - finding variety that lead to useful generalizations .Every 10 years an enumeration of the population is conducted , with data classified by nationality , citizenship , age , gender , race , marital status , educational level , regional and community residence , employment , economic status , births , deaths , and other characteristics .For example , descrip- tive studies of the intellectually gifted , carried on since the early 1920s by the late Lewis M. Terman and his associates , have provided useful generalizations about the characteristics of this segment of the school population .Although these studies did not explain the factors underlying giftedness , they did provide many hypotheses investigated later by more sophisticated experimental methods .Actually , many of the early studies in the behavioral sciences were useful in providing needed generalizations about the behavior or characteristics of individuals and groups .Each of them employs the process of disciplined inquiry through the gathering and analysis of empirical data , and each attempts to develop knowledge .The National Assessment of