What is Statistics?
Statistics is the branch of mathematics that deals with the collection, organization, analysis, and interpretation of data. It helps us make sense of information and draw meaningful conclusions.
What is Data?
Data is a collection of facts, numbers, or observations. Examples include:
- Test scores of students in a class
- Heights of players on a sports team
- Number of cars passing a toll booth each hour
Types of Data:
| Type | Definition | Example |
|---|---|---|
| **Secondary Data** | Obtained from published sources | Data from a government report |
Steps in Data Collection and Presentation:
- Collect the data through observation, surveys, or experiments
- Organize the data in a systematic way
- Present the data in tables or graphs for easy understanding
Frequency Distribution Table:
A frequency distribution table shows how often each value (or range of values) occurs in the data.
Raw Data: 5, 3, 8, 5, 7, 5, 9, 8, 5, 7, 3, 8, 5, 6, 7
Frequency Table:
| Value | Tally Marks | Frequency |
|---|---|---|
| 5 | IIII | 5 |
| 6 | I | 1 |
| 7 | III | 3 |
| 8 | III | 3 |
| 9 | I | 1 |
| **Total** | **15** |