Download - Research methods module 3

1

14MBA23

Research MethodsModule 3

Prof. SANJEEV KUMAR SINGH, Mysuru – 570 022Prof. SANJEEV KUMAR SINGH, Mysuru – 570 022

+91 91640 76660, [email protected]+91 91640 76660, [email protected]

2

14MBA23 – Research Methods

Syllabus: Sampling: Concepts- Types of Sampling -

Probability Sampling – simple random sampling, systematic sampling, stratified random sampling, cluster sampling -Non Probability Sampling – convenience sampling- judgemental sampling, snowball sampling- quota sampling – Errors in sampling.

3


SAMPLING: For a researcher, he needs to gather information

for his study and he selects a part of the population for his study, which resembles by Characteristics, which the researcher wants to be studied.

In simple language, Sample is a unit of the large quantity, it may be products or a part of a population required for the study.

4


SAMPLING: CONCEPTS OF SAMPLING:There may be a number of Concepts in Sampling which can

include,

i) Population (all units in a region),

ii) Sampling Unit (Identifyable units in the population),

iii) Sampling Design (Samples selected based on their possible probabilities),

iv) Sampling frame (The design can be the specific population like Indian Villages or Illiterates and so on),

5


SAMPLING: CONCEPTS OF SAMPLING:v) Random Sample: (Explanation is not required),

vi) Non-Random Simple: (Explanation not required)

vii) Population Parameters: (What basis population can be calculated – Its the mean or its average and variance of the population)

viii) Statistic, Estimator and Estimate: (It need to be calculative, statistical information/ data to be gathered)

ix) Sample Design: (Sample design will specify every possible probability of being drawn)

x) Sampling errors: (Sample error is difference between the statistic used to estimate and the actual but unknown values of the parameters)

6


SAMPLING: CONCEPTS OF SAMPLING:What is mean, median and mode?

Mean – The average., Ex: 3, 4, 6, 1, 3, Add all and divide it gives the mean. (Total/ No of units = Mean – 17/5 = 3.4 is the mean)

Median – The center number in the arranged series, Ex: 3,4,6,1,3 shall be arranged into one 1,3,3,4,6, here in the five numbers, the middle number is 3 Hence 3 is the median,

Mode – The common number in the series, Ex: 3,4,6,1,3 the common number appearing the hightest time is 3 hence Mode is 3.

7


SAMPLING: Purpose/ Features of Sampling:i) Lowering the cost (Economical),ii) Greater accuracy of results (Reliable, Accuracy,

Stability, Scientific – Probability or Non-Probability),iii) Speedy in data collection (Less Time Consuming),iv) Availability of population for test,

8


STEPS IN DEVELOPING SAMPLING PLAN: i) Define the target population, (Characteristics)

ii) Select the data collection method, (Interview, Observation)

iii) Identify sampling frames needed, (Eligible Sampling Units)

iv) Select appropriate sampling method,(Probability or Non Probability Method)

v) Determine necessary sample sizes and overall contact rates, (Sample size, Time and Money Reqd)

vi) Creating an operating plan for selecting sampling units, (How to reach the respondents)

vii) Execution of the operational plan.(Start with consistency and control)

9


Determination of Appropriate Sampling Design:i) What's the research objective,

ii) What is the scope of the research,

iii) What are the availability of resources (Primary resources/ secondary resources),

iv) What is the time required to perform the sampling,

The next is (After the collection of the sample data)

v) Is the target population knowledge adequate,

vi) Is the appropriate tools used for the sampling,

vii) Is the solution accurate.

10


Factors influencing the sample size are:i) Size of the population,

ii) Availability of the resources (Primary or secondary),

iii) Degree of accuracy desired,

iv) Homogeneity (Same) or Hetrogenity (Different) of the population,

v) Nature of Study,

vi) Method of sampling adopted,

vii) Nature of respondents

11


Merits and Demerits of sampling:Merits of Sampling:

i) Sampling saves/ consumes less time,

ii) Sampling provides more information,

iii) Sampling provides information at less cost,

iv) Sampling is scientific,

v) Sampling results are reliable.

Demerits of Sampling: If proper place, time, respondents, techniques or tools, are selected wrong it has lots of demerits, like Inaccuracy, Misleading, or leads to complications and confusions.

12


Errors in Sampling: Errors can be in two types: (a) Biased and (b) Unbiased Errors

(a) Biased Errors are those errors due to bias of prejudice (unreasonable) on the part of the respondent or informant, or/ and on the part of the researcher in selection of respondent, or method of data collection.

(b) Unbiased Errors are those errors which is occured accidental without the knowledge of the researcher,

13


SAMPLING: Types of Sampling or Techniques in

Sampling:i) Probability Sampling,ii) Non-Probability Sampling.

14


SAMPLING: Types of Samplingi) Probability Sampling (Non-Zero Probability),:a) Simple Random Sampling,

b) Systematic Random Sampling,

c) Stratified Random Sampling,

d) Cluster Sampling,

e) Multi-Phase Sampling or Sequential Sampling,

f) Sampling with probability proposition to size.

15


SAMPLING: Types of Samplingii) Non-Probability Sampling,:

a) Convenience Sampling,

b) Judgment Sampling,

c) Quota Sampling,

d) Snowball Sampling,

16


SAMPLING: Types of Sampling - Probability Sampling,:

a) Simple Random Sampling:

Simple Random Sampling refer to the sampling technique where the respondents are gathered randomly. In random sampling this is done as,

i) Every respondent is equally qualified for the selection chosen for the sample,

ii) Every respondent has the equal probability, in determining the results.

Example: Out of 56 students, 10 were taken randomly.

17



b) Systematic Random Sampling: Systematic Random Sampling is the sampling, where out of the target populatio, sample is collected in a systematic manner.

Example: In the class attendance list, every fifth student shall be taken for sampling,

18



c) Stratified Random Sampling: Stratified Random Sampling, refers when the population is divided into certain classes or social layers to form a individual sample.

Example: Sampling stratefied on the basis of caste or religion or education or life style.

19



d) Cluster Sampling: Cluster sampling is a probability sampling method in which the sampling units are divided into mutually exclusive and collectively exhaustive subpopulation called Clusters.

Cluster sampling is 'Single Stage (One Stage)' and 'Multi Stage (Several Stage)' Cluster Sampling, and if distributed geographically then it is 'Area Sampling'.

Cluster sampling may or may not have approximate number of elements/ subjects in each cluster.

20



e) Multi-Phase Sampling: Multi-phase Sampling is also called as Sequential Sampling and Double Sampling as the first sample is taken for preliminary study and further thereon it is taken for more details and further informations.

21



f) Sampling with probability propositional to size:

This refers that the sampling where each sample is selected ramdomly or systematically or stratified, (as per the selection of the researcher), but each sample shall have the same size, for samples tends to have a uniform study.

This sampling is less expensive and the process is more or less, like the simple random sampling.

22


SAMPLING: Types of Samplingii) Non-Probability Sampling,:

a) Convenience Sampling,

b) Judgment Sampling,

c) Quota Sampling,

d) Snowball Sampling,

23


Types of Samplingii) Non – Probability Sampling:

a) Convenience Sampling: i) Convenience Sampling is a Non-Probability Sampling.

ii) Convenience Sampling is the sampling where the researcher has the freedom to choose sampling of his choice or convenient.

Iii) Convenience Sampling is usually performed during the Exploratory Research Phase of a research project.

iv) Convenience Sampling is the method where the researcher is able to collect informations quickly and efficienctly.

24



b) Judgment Sampling: i) Judgment Sampling is a non-probability Sampling,

ii) Judgment Sampling is used in exploratory research process,

iii) Judgment Sampling is selected on researcher's beliefs to meet the research,

iv) Judgment Sampling is performed to collect information which is advantageous to the researcher.

25



c) Quota Sampling: i) Quota Sampling is a Non-Probability Sampling,

ii) Quota Sampling is selection on pre-specified quotas,

iii) Quota Sampling is selection based on Age, Sex, Occupation, Income or Rural or Urban and so on.

iv) Quota Sampling can be based on demographic specifications, like Nanjangud Area, Siddartha Lay out, MBA Students.,

v) Quota Sampling is done to ensure that the group/ quota selected is able to adequately represent the study.

26



d) Snowball Sampling: i) Snowball Sampling is another non-probability Sampling,

ii) Snowball Sampling is also called as 'Referral Sampling'.

iii) Snowball Sampling makes the respondent to refer another potential respondent,

iv) Snowball Sampling is usually done where the respondents are small in number and unique to fulfill the requirement in the research.

27


End of Module 3

Download - Research methods module 3

Top Related