This study is to analyse and interpret the educational data of the 1990 census of population and housing in Taiwan. Data were used to test various theories in the field of educational sociology. Major findings are: (a) The opportunity theory of crime is supported: the more prosperous a society is, the higher the crime rate will be this is due to the fact that in a prosperous society, more objectives of crime are available. Therefore the hypothesis: "crime is a byproduct of freedom and prosperity" can be supported. (b) Delinquency behavior can be reduced through education. Because by comparing the percentage of different educational attainment between the offenders and the civilian population aged 15 years and over it is found that, those offender, whose educational level higher than junior high school is, have lower percentage relative to the civilian population. It is possible that education will reduced the offense motivation. (c) Taiwanese society is undergoing structural mobility. Checking the four census carried out in the past time in Taiwan, a upward trend of the degree of vertical labor division in education as well as in occupation has been found. (d) Education has a positive effect on occupation: the his her a person's educational attainment is, the higher his opportunity of reaching high occupation will be, and this rule is also valid for his salary. This phenomenon can interpret why so many young ones pursuing advanced studies. But in a knowledge-intensive society, professional knowledges become harder to be learned without the instructions in the educational institutions. The pursuit of advanced studies should be regarded as to acquire a chance to learn professional knowledges. (e) If the percentage of different academic field of unemployed is compared with that of labor force, it is easy to finger out which academic field has higher risk of unemployment. In this study, a formula is suggested to calculate the unemployment index. This index would be a valuable information for those, who want to choose academic field for their advanced study. It would also be helpful for the government to screen the applications for the establishments of new departments of higher educations. (f) An aptitude differentiation between both sexes by the choice of academic field has been found in the vocational high school and in higher education. Male students tend to choose hard science and female students are more likely to choose soft science as the subject of their studies.