Introduction of Six Sigma _ Basic Statistics #1

Basic Statistics

   1. Statistical Definition
      - A system of theories and methods for sensible decision making in uncertain situations
      - A system of theories and methods to understand characteristics of the whole 
        from partial data
   2. Types of Statistics
       - Descriptive Statistics
            A statistical technique summarizes or describes  a set of data 
            through a single number or graph.
       - Inferential Statistics
            A method that takes chance factors into account when samples are used 
            to reach conclusions (or make inferences about) populations.
   3. Population and Sample
       - Population and Sample
            . Population: The entire group of subjects of interest
            . Sample: A part of the population of interest
      - Parameter and Statistics
            . Parameter: A numerical characteristic of a population; denoted by a Greek letter
            . Statistics: A numerical characteristic of a sample; denoted by a Roman letter