Sampling sample universe basis of sample advantage limitations

1. Presentation on
Sampling – universe sample & sampling – meaning, basis for sampling, advantages
limitations
Course no. – EXT-504
Course Credit – 3(2+1)
Course Title – Research methods in behavioral science
Submitted To :- Submitted by :-
Dr. M.A. khan Namita Pradhan
Dept. of Extension Roll no.- 20200143
IGKV Raipur M.sc 1st year 2nd sem

2. Content :-
 Sample
 Universe
 Importance of sampling
 Process of sampling
 Sampling method
 Advantages
 limitations

3. Sample :-
 ‘Segment of population or universe’
 A subset of the population
Meaning :-
In simple words sampling consists of obtaining information from a larger group or a
universe.
A social researcher has to collect information about a universe that consists of vast,
differentiated population spread over a large territory and that too with in a limited amount
of time and money.
Measuring or collecting information from each and every member of such a vast
population is, therefore, always not possible. It is known that part of a whole can give
sufficient dependable information if the procedures followed in collection the part has of
been scientific.
Sampling :- When a small part of the population is selected for study

4. SAMPLING: THEORETICAL BASIS
 On the basis of sample study we can predict and generalise the behaviour of mass
phenomenon.
 This is possible because there is no statistical population whose elements would vary from
each along without limit.
 Though we final diversity is a universal quality of mass data, every population has
characteristic properties with limited variation.
 Thus makes possible to select a relatively small unbiased random sample that can portray
fairly well.
 There are two important laws on which the theory of sampling is based:
Law of 'statistical Regularity’
Law of 'Inertia of Large Number

5. Universe :-
 In sample language, a population or universe can be defined as any collection of persons or
objects or event in which one is interested.
 In other words a population consists of the people who are related to the specific problem
under investigation.
 For example, if we are studying the relationship between the class achievements of the
university students and the methods of teaching then the students of any place and of any
time will come under our population. If we are studying the voting behaviour or political
participation of the citizens of India then all the adult citizens of India, living in India or
outside will come under population.
Universe Types :-
 Uni variate population
 Bi- variate population
 Multi variate population

6. Importance of sampling :-
 Saving time
 Saving resources
 For detailed studies
 Accuracy of result
 Administrative convenience
 Impossibility of taking all population
 Easy for analysis

7. Process of Sampling :-
Define population
Sampling Frame
Sampling unit
Sampling method
Sampling size
Sampling plan
Select the sample

8. Type of sampling method
 Probability sampling methods :- The size of universe is known each individual has a chance
of selection.
1. Simple random sampling :- Each individual have equal & independent chance of selection.
2. Systematic sampling :- Select every (nth) item from the population (n=sampling interval)
3. Stratified random sampling :- useful in heterogeneous pop
Proportionated stratified random sampling.
Disproportionate stratified random sampling.
4. Multistage random sampling :- Selection in different stages (state, district, village)
5. Cluster sampling :- One representative group, convenient.

9. 6. Sequential sampling :- First very small size of sample and draw conclusion, if not fit some more
sample add and so on.
7. Replicated sampling :- Whole divided into groups and select groups of sample.
 Non- probability sampling :- not necessary of equal chance, selected deliberately by
the researcher.
1. Purposive sampling :- selection by choice.
2. Quota sampling :- selection by quota according to age, education etc.
3. Convenience sampling :- According to convenience of researcher.
4. Double sampling :- From universe to big sample and again required relationship.

10. Advantages :-
 Helps to collect vital information more quickly.
 It has a greater adoptability.
 It is an economical technique.
 It has high speed for generalization.
 This technique has great accuracy.
 It has a greater speed in conducting a research work.
 It has a greater scope in the field of research.
 It reduces the cost of observation or data collection

11. Limitations :-
 Results obtained may be incorrect or misleading.
 Sampling is to be done by qualified and experienced persons. Otherwise the information
will be unbelievable.
 Sample method may sometimes give the extreme values.
 Appropriate sampling techniques is used.
 The sampling units are drawn is a scientific manner.
 Small sample is not always good.
 A complicated sampling may require more time, money, labour.
 Not possible to ensure representativeness.

12. Thankyou