35 This point was made during the course of the Expert Group Meeting by the particl-· pant from the United States. so model building; little progress has been made owing to the lack of statis­ tical contents of social indicators and of established theories relating eco-. nomic and social factors. The available series of _social statistics are not only extremely -limited, but· also lack universally applicable definitions and data. Despite data limitations, pioneering works in this area were attempted independently ·by Fredrick Harbison and others 36 ·and by · Irma Adelman and Cynthia T. Morris.37 In their studies, the authors seem to have struggled a great deal in search of appropriate quantitative · techniques for their analysis .. Harbison and others applied the.so-called taxonomic method while Adelman and Morris relied on factor analysis. Both · of these pioneering studies succeeeded in distinguishing socio­ politico-economic factors significant and insignificant for development. Although these attempts did not succeed in showing the causative rela- . tionships of sod-economic factors and in advancing explanatory models for development, they opened a new area of academic exploration and possibility for the future. 52. More recently, an attempt has been made by the national plan­ ning agency of Japan to relate socio-economic variables in a systems · dynamic modeI.38 The results of this attempt were not formally pub­ lished, but it represented a healthy effort to check if development poli­ cies were consistent with changes in the quality of life and well-being. There are also efforts to expand a traditional macro-economic model py introducing a number of structural equations using social indicators.39 The results of this effort are still a prototype experimentation requiring further tests · and verifications for practical application. Nevertheless, the study is an important beginning in the application of social indicators to development planning. · , E. CONCLUSIONS 