Manufacturing
companies are most concerned with variation and its effect on product
quality.
The field of knowledge that deals with counting and
measuring is known as "statistics". The art of organizing numerical
information is often called descriptive statistics. Examples of
descriptive statistics can be found in all branches of business
and not only manufacturing. More and more they are being referred
to as information systems and are being stored and calculated on
computers. The purpose of these systems is to define and monitor
an on-going activity to provide a guide for action.
Statistical concepts most needed to understand
variation include:
Statistical measures (mean,
variance, standard deviation, etc.) Distributions and Probability
Comparing samples
Confidence Intervals
Regression & Correlation
Analysis of Variance