CHAPTER 1: WHAT IS STATISTICS?
1.1 AN OVERVIEW OF STATISTICS
is the science of learning from data. This means that
is a method of
extracting information from data. It involves rules and procedures for collecting (by
statistical surveys), classifying, summarizing, presenting (in tabular or graphical form; or
by summary statistics), analyzing and interpreting
to assist in
making prompt and more effective decisions when faced with uncertainty.
The work of the statistician is no longer confined to gathering and tabulating data, but is
chiefly a process of interpreting the information and making predictions. In making
uses the companion subject of
. The development of the
theory of probability increased the scope of statistical applications. Many data can be
approximated accurately by certain probability distributions, and the results of probability
distributions can be used in analyzing statistical data. Probability can be used to test the
reliability of statistical inferences and to indicate the kind and amount of data required for
a particular problem.
has become an important tool in the work of many academic disciplines
, just to
name a few. Statistics is also important in many aspects of society such as
. Because of the increasing use of statistics in so many areas of
our lives, it has become very desirable to understand and practice statistical thinking.
This is important even if you do not use statistical methods directly.
1.2 EXPERIMENTAL UNIT and TYPES OF VARIABLE
) is an object or individual (
transaction, event, activity, or person, or some unified group or institution) upon which
we collect data either in an
or in an
, respectively. When
) deals with
) are called
Dr. LOHAKA – QBA 2302 Chapter 1:
WHAT IS STATISTICS?