FRAME 20. (Continued)
One of the tools available to the manager is STATISTICS. Increasing numbers of executives
desire the guidance of statistical analysis in making decisions. This growing use of statistical
methods in business has been paralleled by a new emphasis on statistics by Government
agencies. Government and business generate, manipulate, store and print incredible quantities
of raw data. Statistics is a science that concerns itself with the measurable properties of a "pile
of data" or group of objectives and thus can be helpful in bringing some order to the chaos.
We might separate statistics into closely related categories of quantitative techniques. These
two categories are commonly called DESCRIPTIVE and INFERENTIAL statistics.
We use DESCRIPTIVE statistics to marshall and put data into some organized structure that
has meaning to the manager or decision maker. We attempt to identify those measurable
properties mentioned earlier, and to attach a number or value to them. We also try to identify a
"shape" or form for the data, and relate that shape to some known shape that has thoroughly
understood and documented characteristics.
We use INFERENTIAL statistical techniques to analyze the data and draw a conclusion or
conclusions from the results of the analysis. In doing so, we, as analysts, go beyond the data
collected, and predict, with some measure of accuracy, quantities to be realized.
There are terms in statistics that we will need to know.
The POPULATION is a set of data which consists of all possible observations of a certain
event. Another definition might be the totality of persons, items, time periods, equipment, and so
forth, with a common characteristic. Perhaps the simplest definition would be to call the
population the WHOLE, whatever we define it to be.
Examples would include such disparate populations as all the people in the world who are US
citizens, all the automobiles produced by General Motors last year, all the tanks currently in the
Army inventory, all the members of a specified platoon, or all the people in your family.
Should we decide to look at each item in a population, we would be performing a CENSUS.
Usually we can not perform a census. Some reasons which may deter us from doing a census
include lack of time, prohibitive expense, destructive nature of the census, and changing
characteristics of the population. In these situations, we examine a SAMPLE drawn from the
population in question.
The SAMPLE is a set of data containing only a part of all the observations found in the
population. It is a part or a subset of the population. More simply, a sample is just a part of the
whole. We sample quite frequently. For example, when