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Statistics There were two widely divergent influences on the early developmentof statistical methods. Statistics had a mother who was dedicated to keepingorderly records of governmental units and a gentlemanly gambling father who relied onmathematics to increase his skill at playing the odds in games of chance. The influence of the mother on the offspring, statistics, isrepresented by counting, measuring, describing, tabulating, ordering, and the taking of censuses -- all of which led to modern descriptive statistics. From the influence of the father came modern inferential statistics, which is based squarelyon theories of probability. Descriptive statistics involves tabulating, depictingand describing collections of data. These data may be quantitative such asmeasures of height, intelligence or grade level -- variables that arecharacterized by an underlying continuum -- or the data may representqualitative variables, such as sex, college major or personality type.Large masses of data must generally undergo a process of summarization orreduction before they are comprehensible. Descriptive statistics is atool for describing or summarizing or reducing to comprehensible form the properties of an otherwise unwieldy mass ofdata. Inferential statistics is a formalized body ofmethods for solving another class of problems that present great difficulties for the unaided human mind. This general class of problemscharacteristically involve attempts to make predictions using a sample of observations. For example, a school superintendent wishes to determine the proportion ofchildren in a large school system who come to school without breakfast, havebeen vaccinated for flu, or whatever. Having a little knowledge of statistics, the superintendent would know that it is unnecessary andinefficient to question each child: the proportion for the entire district couldbe estimated fairly accurately | 
