**1.
Probability Sampling**

Probability sampling methods are such methods of selecting a sample from the population in which all units of the universe are given equal chances of being included in the sample.

**Types of
Probability Sampling:** The various probability
sampling are as follows:

(a) Simple Random Sampling: This is the simplest and most popular technique of sampling. In it, each unit of the population has equal chance of being included in the sample.

**(b) Systematic Sampling:** In this sampling, one unit is selected at random from the universe and the other units are at a specified interval from the selected unit.

**(c)
Stratified Random Sampling:** Stratified random sample is
one in which random selection is done not from the heterogeneous universe as a
whole but from different homogeneous parts or strata of a universe.

**(d) Cluster Sampling:** In this method, the universe is divi which are called clusters. After this, a simple random sample the units belonging to the selected clusters constitute the sample.

**(e)
Multi-Stage Sampling:** This is a modified form of cli
all the units in a selected cluster constitute the sample celected in two,
three or four stages.

**(f) Area
Sampling:** Area Sampling is a form of multi-stage lists or
registers are used as the sampling frame. It is me do not have a satisfactory
sampling frame such as a population
list.

**11.
Non-probability Sampling**

Non-probability sampling is that sampling proc estimating the probability that each item in the populat probability sampling is also known by different names such as sampling and judgement sampling.

**(a)
Convenience Sampling:** In convenience sampling
sampling units on the basis of convenience or accessibility. It is called
accidenta sample-units enter by accident.

**(b) Purposive Sampling:** A non-probability sample that conforms to certain is called purposive sampling. Purposive sampling is basically of two types-judgement sampling and Quota sampling.

**(C) Panel
Sampling:** Panel sampling is the method of first selecting a
group of participants through a random sampling method and then asking that
group for the same information several times over a period of time.

**(d) Snowball Sampling:** It is a special non-probability method used when the desired sample characteristic is rare. Snowball sampling relies on referrals from initial subjects to generate additional subjects. While this technique can dramatically lower search costs, it comes at the expense of introducing bias because the technique itself reduces the likelihood that the sample will represent a good cross section from the population.