Introduction of Statistics (PDF)

Introduction of statistics  Out line  Definitions of terms  Statistical Methods  Types of Statistics  Difference between descriptive and inferential studies.  Statistics Statistics simply means numerical data, and is field of math that generally deals with collection of da...

Introduction of statistics  Out line  Definitions of terms  Statistical Methods  Types of Statistics  Difference between descriptive and inferential studies.  Statistics Statistics simply means numerical data, and is field of math that generally deals with collection of data, tabulation, and interpretation of numerical data. It is actually a form of mathematical analysis that uses different quantitative models to produce a set of experimental data or studies of real life.  :Definitions of terms  Statistics is a tool that aids in organizing , summarizing and communicating findings (data) clearly and meaning full.  Medical statistics/ Biostatistics is the science that applies the principles of statistics in the field of health  Data is the basic building blocks of statistics  Importance of Statistics  Statistics executes the work simply and gives a transparent picture of the work we do regularly.  The statistical methods help us to examine different areas such as medicine, business, economics, social science and others.  Statistics equips us with different kinds of organized data with the help of graphs, tables, diagrams and charts.  Importance of Statistics  Statistics helps to understand the variability of the data pattern in a quantitative way  Statistics makes us understand the bulk of data in a simple way  Statistics is the way to collecting accurate quantitive data  Population and parameter  Population (N): is all elements (can be people or things)whose characteristics are being studied.  A value (average, total, etc.) that is calculated from the entire population is called a Parameter.  Sample and statistic  A sample (n): is a subset of the population that is selected for study.  A value that is calculated from a sample is called a statistic.  Sample (n): consists of one or more observations from the population.  Subjects are the units on which characteristics are measured. In medicine and public health, the subjects are most frequently humans, but might also be cells in culture or animals used in research.  Statistical Methods A)Methods of data collection B) Analytic statistics C) Methods of data presentation ?What is data  Data are observations or evidences about the social world.  can be quantitative or qualitative in nature.  ‘Data are produced, not given; that is, researchers choose what to call data, it is not just ‘there’ to be ‘found’.  Data, information What is information? Information is data that have been processed to make them meaningful and useful. Data + Meaning = Information. For example, individual exam marks are raw data, but if you were to process those to say that boys did better than girls, or that 76% of the students in your school got a grade A or B, then that is information.  :Source of data Main source of demographic data: 1. Census 2. Vital registration 3. Official records 4. Simple survey 5. Individuals studied 1- census:  It is full coverage for all people within specific boundaries at a specific point in time (census night) Objectives 1. To determine total size of population. 2. To obtain detailed information (age, sex, education, economic activity, occupation, etc..) about the population + other information.  Nature of Data The data can be classified into two broad categories: : Dat a Qualitativ Quantitative e Data Data or or Variables Attributes  Types of Statistics  Descriptive / Deductive  Inferential /inductive  Descriptive statistic  Techniques to organize, display, and describe data using tables, graphs, and summary measures.  Inferential statistics  Techniques that enable us to use information gathered from a sample to make decisions, inferences, or predictions about a population.  Statistic and Research  Statistics are used to analyze the data collected in a research study.  Example: Suppose research participants taste both Diet coke and diet Pepsi and indicate which one they prefer.  We have observed a difference (descriptive), but is this difference meaningful??.  Using statistics, we can determine if there is a meaningful difference between the number of people who preferer each soda! (Inferential). : Types of Statistics