Introduction to Statistics // Basic statistic chapter one በ አማርኛ

Definition statistics Statistics is defined as the science of collecting, organizing, presenting, analyzing and interpreting numerical data for the purpose of assisting in making a more effective decision Classification OF Statistics Depending on how data can be used, statistics is sometimes divided in to two main areas or branches. 1. Descriptive Statistics: is concerned with summary calculations, graphs, charts and tables. 2. Inferential Statistics: is a method used to generalize from a sample to a population There are five stages or steps in any statistical investigation Collection of data Organization of data Presentation of the data Analysis of data Inference of data Definitions of some terms Statistical Population Sample Sampling Sample size Census Parameter Statistic Variable Types of Variables or Data Qualitative Variables Quantitative Variables Applications of statistics Uses of statistics Limitations of statistics Scales of measurement Order Distance Fixed Zero SCALE TYPES Nominal Scales Nominal scales are measurement systems that possess none of the three properties stated above. Ordinal Scales Ordinal Scales are measurement systems that possess the property of order, but not the property of distance. The property of fixed zero is not important if the property of distance is not satisfied. Interval Scales all arithmetic operations except division and multiplication are applicable Ratio Scales all arithmetic and relational operations are applicable.