Probability and Statistics, According to **R A fisher** statistics is a branch of applied mathematics that specializes in data.

### What are the main divisions of statistics?

**Theoretical Statistics**:- It covers the development of statistical distributions, experimental designs, etc..

**Statistical Methods**:- It covers the collection, tabulation, analysis, and interpretation of data.

**Descriptive statistics**:- Data classification and representation in a diagrammatic format.

**Inferential statistics**:- To make a generalization about a population based on a sample taken from it.

**Applied statistics**:- Mainly covers population, census, income, production, business statistics, industrial statistics, quality control, biostatistics, etc.

How to measure the association between the ranks? »

### Limitations

1) Only numerical data is dealt with in statistics. In order to be analyzed, even qualitative data must be converted to quantitative.

2) Statistics are only accurate on average.

3) In general, statistical results are valid. They are always prone to some degree of inaccuracy.

4) Statistics is merely a tool for drawing population conclusions, not a cure for all problems.

### Investigations

There are mainly two types of investigations.

**Census method**:-To include every single unit or object in the population under investigation.

**Sample Method**:- An investigator must pick a subset of the population and develop findings based on those subsets.

### Functions of Statistics

There are four functions of statistics

- Collection of data
- Presentation of data
- Analysis of data
- Interpretation of data

### Types of Statistical Data

There are two types of statistical data

**Primary Data**:- These are directly taken from units or individuals, and have never been utilized for any reason before.

**Secondary Data**:- Somebody had gathered data and statistically treated it in order to derive specific conclusions. The same data is used and examined again to derive additional information.

### What is mean by reliable data?

The requisites of reliable data are

- It should be complete
- It should be consistent
- It should be accurate
- It should be homogeneous

### Probability and Statistics

Probability denotes the possibility of something happening. It’s a field of mathematics that studies the probability of a random event occurring.

From 0 to 1, the value is expressed. Probability is a mathematical concept that predicts how likely occurrences are to occur.