Definition: - Statistics is a group of methods used to collect, analyze, present, and interpret data and to make decisions.
Every day we make decisions that may be personal, business related, or of some other kind. Usually these decisions are made under conditions of uncertainty. Many times, the situations or problems we face in the real world have no precise or definite solution. Statistical methods help us make scientific and intelligent decisions in such situations.
Example: - Opening a large store with or without assessing the need for it may affect its success.
Other example: - We may want to find the starting salary of a typical college graduate. To do so, we may select 2000 recent college graduates, find their starting salaries, and make decision based in this information.
Types of statistics:- There are two types of statistics:
· Descriptive statistics
· Inferential statistics
Descriptive Statistics consists of methods for organizing, displaying, and describing data by using tables, graphs, and summary measures.
Inferential statistics consists of methods that use sample results to help make decisions or predictions about a population.
This branch of statistics is also called inductive reasoning or inductive statistics.
Note: - In statistics, the collection of all elements of interest is called a population. The selection of a few elements from this population is called a sample.