Sampling Meaning needs and modes by shohrab

what is sampling?
WHAT ARE THE MODES?
WHAT ARE THE NEEDS?
AND ITS MEANING.
This was a presentation that was carried out in our research method class by our group. It will be useful for PHD and master students quantitative and qualitative method. It consist sample definition, purpose of sampling, stages in the selection of a sample, types of sampling in quantitative researches, types of sampling in qualitative researches, and ethical Considerations in Data Collection.

1. JSPM’s
Rajarshi Shahu College of Engineering
Tathawade , Pune:33
Presentation on
“ Topic –Sampling –Meaning, Need and
modes”
Department of MBA
Date : 04/05/2021
Guided By : Dr. Amey Choudhari
Name of student: Shohrab Agashe
Roll Number : RMB20MB020
Subject : Research Methodology
(Mba-I Sem I)

2. Definition of Sampling
Sampling is A technique of selecting individual members or A
subset of the population to make statistical inferences from them
and estimate characteristics of the whole population.
For example, if a drug manufacturer would like to research the
adverse side effects of a drug on the country’s population, it is
almost impossible to conduct a research study that involves
everyone. In this case, the researcher decides a sample of people
from each demographic and then researches them, giving him/her
indicative feedback on the drug’s behavior

3. What is the need of Sampling?
Thepopulationofinterestisusuallytoolargeto
attempttosurveyallofitsmembers.
Acarefullychosensamplecanbeusedto
representthepopulation.
Thesamplereflectsthecharacteristicsofthe
populationfromwhichitisdrawn.

5. Probability versus Nonprobability
ProbabilitySamples:eachmemberofthepopulation
hasaknownPositivechancesofbeingselected
Methodsincluderandomsampling,systematicsampling,and
stratifiedsampling.
NonprobabilitySamples:membersareselectedfrom
thepopulationinsomenonrandommanner
Methodsincludeconveniencesampling,judgmentsampling,
quotasampling,andsnowballsampling

6. Simple Random Sampling
Randomsamplingisthepurestformofprobability
sampling.
Eachmemberofthepopulationhasanequalandknown
chanceofbeingselected.
Whenthereareverylargepopulations,itisoften‘difficult’to
identifyeverymemberofthepopulation,sothepoolof
availablesubjectsbecomesbiased.
Youcanusesoftware,suchasminitabtogeneraterandom
numbersortodrawdirectlyfromthecolumns

7. Systematic Sampling
Systematicsamplingisoftenusedinsteadofrandom
sampling.ItisalsocalledanNthnameselection
technique.
Aftertherequiredsamplesizehasbeencalculated,every
Nthrecordisselectedfromalistofpopulationmembers.
Aslongasthelistdoesnotcontainanyhiddenorder,
thissamplingmethodisasgoodastherandom
samplingmethod.
Itsonlyadvantageovertherandomsamplingtechnique
issimplicity(andpossiblycosteffectiveness).

8. Stratified Sampling
Stratifiedsamplingiscommonlyusedprobabilitymethod
thatissuperiortorandomsamplingbecauseitreduces
samplingerror.
Astratumisasubsetofthepopulationthatshareatleastone
commoncharacteristic;suchasmalesandfemales.
Identifyrelevantstratumsandtheiractualrepresentationin
thepopulation.
Randomsamplingisthenusedtoselectasufficientnumberof
subjectsfromeachstratum.

9. Cluster Sampling
Cluster Sample: a probability sample in which each
sampling unit is a collection of elements.
Examples of clusters:
City blocks –political or geographical
Housing units –college students
Hospitals –illnesses
Automobile –set of four tires

10. Non-probability sampling

11. Convenience Sampling
Conveniencesamplingisusedinexploratory
researchwheretheresearcherisinterestedingetting
aninexpensiveapproximation.
Thesampleisselectedbecausetheyareconvenient.
Itisanonprobabilitymethod.

12. Judgment Sampling
Judgmentsamplingisacommonnonprobability
method.
Thesampleisselectedbaseduponjudgment.
anextensionofconveniencesampling
Whenusingthismethod,theresearchermustbe
confidentthatthechosensampleistruly
representativeoftheentirepopulation.

13. Quota Sampling
Quotasamplingisthenonprobability
equivalentofstratifiedsampling.
Firstidentifythestratumsandtheir
proportionsastheyarerepresentedinthe
population
Thenconvenienceorjudgmentsamplingis
usedtoselecttherequirednumberof
subjectsfromeachstratum.

14. Snowball Sampling
Snowballsamplingisaspecialnonprobabilitymethod
usedwhenthedesiredsamplecharacteristicisrare.
Thistechniquereliesonreferralsfrominitialsubjectsto
generateadditionalsubjects.
Itlowerssearchcosts;however,itintroducesbias
becausethetechniqueitselfreducesthelikelihoodthat
thesamplewillrepresentagoodcrosssectionfromthe
population.

15. THANK YOU