**DEFINITION OF STATISTICS**

Statistics is a scientific activity which

deals with the theories and methods of

collection, analysis and interpretation of

such data.

**APPLICATION OR USES OFBIOSTATISTICS**

1- It deals in presenting large quantity of data in a simple

and classified form.

2- It helps in finding the relationship between the

variables.

3- It proves useful in number of fields like railways, banks,

army etc.

4- It gives the method of comparison of data and judges

them in a right manner.

5- It helps to provide good material for the businessmen

as well as the administrator.

**CHARACTERISTIC OF STATISTICS**

1- Statistics are the aggregate of facts.

2- It can be numerically expressed.

3- Statistics must be related to some field of inquiry.

4- Statistics are collected for predetermined

purpose.

5- Statistics are affected by multiplicity of causes

and not by single cause.

6- It should be capable of being placed in relation to

each other.

**LIMITATIONS OF STATISTICS**

1- It does not deal with individual items.

2- It does not depict entire story of phenomenon.

3- It is liable to be misused.

4-Results are true only on average.

5-Too many methods to study problems.

6- Data can not be expressed in qualitative terms.

7- Statistical results are not always beyond doubt.

**SAMPLE AND POPULATION**

*Population:*

Population in statistics means the whole of

the information which comes under the preview of

statistical investigation. It is the totality of all the

observations of a statistical enquiry.

The number of units or members consisting a

population is known as size of population.

There are two types of population:

1- Finite Population

2- Infinite Population

Sample :

A part of the population selected for the study is

called a sample. Samples are usually a relatively small

number of observations taken from a relatively large

population or universe.

For eg. A house wife tests a small quantity of rice to

see whether it has been cooked or not. This small

quantity of rice is a sample

**COLLECTION OF STATISTICALDATA**

Definition of Statistical Data:

A sequence of observation made on a set of

objects included in the sample drawn from the

population is known as statistical data.

There are two types of data:

1-Ungrouped data: Data which have been arranged

in a systematic order are called ungrouped data or

raw data.

2-Grouped data: Data presented in the form of

frequency distribution is called grouped data.

**COLLECTION OF DATA**

The first step in any investigation is collection of data.

There are two types for collection of data:

1- Primary Data: The primary data are the first hand

information collected, compiled and published by

organization for some purpose. They are most original

data in character and have not undergone any sort of

statistical treatment.

2- Secondary Data: The secondary data are second hand

information which are already collected by someone for

some purpose and are available for the present study.

The secondary data are not pure in character and have

undergone some treatment at least once.

**VARIABLES**

The characteristics which can be measure are known

as variables.

The quantity which can be numerically expressed

in terms of units and also they can be measured by

quantitative method.

For eg. Height, weight, marks etc.

Discrete Variables: Discrete variables are those

variables which take only certain value and none in

between. In case of discrete variables the quantity

are measured in whole in tabular values and they

can not take any fractional value.

For eg. height of students,weight, marks, blood

group etc.

Continuous Variables:

Continuous variables are those variables

which have no gaps in between.

In other words those quantities which can

take any value with in a specific range is known

as continuous variables.

For eg: Marks of students are divided into a

class interval of 40-50 marks and corresponding

to these marks 5 students lie within the range but

it does not have a specific value or fixed value.