Unit 2 - Statistical Survey

8/6/2019 Unit 2 - Statistical Survey

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STATISTICAL SURVEY


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Definition

A statistical surveyis a scientific process of

collectionandanalysis ofnumericaldata.


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Stages of statistical survey

Planning

Execution


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Stages of planning

Natureof problem tobeinvestigatedandclearly

defined

Objectives shouldbeclearly stated

Scopeofinvestigationtobeidentified

DeterminethenatureofDatatobe

collected(Primaryor secondary)

Organizationofinvestigation


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Basic Terms

Units or Individuals

Theobjects on which thecharacteristics aremeasured

Populationor Universe

Thetotalityofall Units areindividuals ina survey

1. FinitePopulation

2. Infinite population


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Basic Terms

Sample

A partor subsetofthe population

Quantitativecharacteristic ? Qualitativecharacteristic ?


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Basic Terms

Variable

The quantitativecharacteristicthat varies from unittounit

Attribute

The qualitativecharacteristicthat varies from unittounit

Discrete Variable

Variable Thatassumes only specified values

Example : No.Ofchildren per family


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Basic Terms

Continuous Variable

Variablethatassumes allthe values inthe range

Example : Heightof persons


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Data Collection PrimaryData

Data Collectedfor thefirsttime keepingin view

theobjectiveofthe survey

More reliable

High Costinvolved

A sample which consists ofentire populationis

calledcensus.


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Methods ofPrimaryData Collection

DirectPersonal Interview

IndirectOral Interview

Informationthrough Agencies Informationthrough MailedQuestionnaire

Information Through Schedule


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DirectPersonal Interview

Investigator meets the respondent

Accuracydepends onthe knowledgeandattitude

of theinvestigator

When ?

1. Scopeofinvestigationis narrow

2. Investigationis confidentialand requires personal

attention

3. Accuracyis important


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Merits ofDirectPersonal Interview

Accurateand reliable

IndirectQuestioningis possible

Datais homogenous andcomparable Additional Informationcanbegathered

Misinterpretationcanbeavoided


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Demerits ofDirectPersonal Interview

Most Costly

Time Consuming

If scopeofinvestigationis wide , wecannot useit Informationleakageis possible


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IndirectOralinterview

Canbe used whenareatobecoveredis large

Investigator collects datafrom athird party

(Example : Enquirycommissions)


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Merits & Demerits OF IndirectOral

Interview

Economical whencomparedtoDirect personal

Interview

Confidentialdatacanbecollected

Likelytobe unbiasedand reliable

Demerit:

Degreeof Accuracy maybeless


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Collecting Informationthrough Agencies

Data willcollected Through localor national

reseach agencies

(Ex: Nielsen Company)

When ?

1. Areais verylarge

2. Periodicinformationtobecollected

3. Demerit:

Less quality


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Datafrom MailedQuestionnaire

QuestionnairetobeMailedtothe respondents with

acoveringletter

Objectives tobeexplainedinthecoveringletter

Respondents fillthe questionnaireand sends back.

KeyFactor:

Proper DesigningofQuestionnaire


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How tocreatea successful

questionnaire

It shouldbe smallandnotlengthy

Well structuredandclear

Proper Logical sequence

Questions shouldnotdisturbthe privacyof respondents

Not manydescriptive questions

Clear instructions tobegiveninthecoveringletter

Completed questionnaire shouldbe keptconfidentialand usedfor thecollected purposeonly.

Nochancetobegivenfor misinterpretationof questions


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Types of questions

ContingencyQuestions :

Questiontobeansweredonlyifthe respondentgivesparticular answer tothe previous question.

Ex:Doyou like Chocolates ? Yes [ ] No [ ]

Ifyes , which chocolateyou like

Dairy milk [ ]

Munch [ ]

Kit kat [ ]

Others [ ]


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Types ofQuestions matrix question


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Closedended questions

Thechoices to respondents are restrictedone. The respondents havetochooseonlyfrom theavailableoptions. (yes or no / Multiplechoice)

Example :

Doyou likeB

ollywoodFilmsYes [ ]

No [ ]

Types ofdataavailableare

Primarydata [ ]

SecondaryData [ ]Noneofthe Above [ ]

Allofthe Above[ ]


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ClosedendedQuestions

Scale rating questions Respondents areaskedtoratethe statementina 5 pointor 3 point scale

Example:

I like Chennai skillsA. Strongly Agree [ ]

B. Agree [ ]

C. Neither AgreeNor Disagree [ ]D. Disagree[ ]

E. StronglyDisagree [ ]


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Openended questions

Itis descriptiveinnature. The respondents has to

writetheanswers.

Sentence Completion

Example :

I likePepsibecause ..

..


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Openended questions

Storycompletion

Picturecompletion filltheemptyconversation

balloon

Thematic Appreciation Test explaina picture


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Informationthrough schedules

Inthis method a scheduleor questionnaire willbe

designedandgettingfilledbytheinvestigator

trough personalcontact.


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SecondaryData

Anyinformationthatis collectedand usedearlier

for adifferent purpose , usedfor another purpose

is called the secondarydata

This kindofdatacanbecollectedfrom either a

disclosedor undisclosed source.


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Published sources

Reports andofficial publications ofinternational

andnationalorganizations

Publications from government sources

Journals and magazines

Annual reports ofcompanies

Publications of research scholars and research

agencies


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Unpublished sources

Unpublisheddataofgovernment resources

Reports of privateoffices

Un published research works


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Measures tobeconsidered

Collectionand processingofdata

Accuracyofdata

Thedegreeof summarizationof data

Thedegreeofcomparability

Proper interpretationof data


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Merits of secondarydata

Secondarydatais cheaper

Large quantitycanbeobtained

Timeand moneycanbe savedinalargeextent


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Demerits of Secondarydata

Difficulttojudgetheaccuracyandapplicability

Difficultyin selectinga suitabledata

Someextentof primarydata maybeneeded


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Differencebetween primaryand

secondarydata

Primary Data Secondary Data

Original.Moreaccurate

and reliable

Not reliable

Data collection is

expensive

Itis not expensive

Noteasilyaccessible Easily accessiblethrough

internetor other resources

Datais homogenous Datais not homogenous

Timeconsuming Nottimeconsuming

Extracarenot needed Extracareis required

Datagives detail

information

Data maynotbeadequate


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Pilot Survey

A Trial survey undertakenbeforethe main survey

Reduces inconveniences andloss ofinformationin

the main questionnaire

Helps toidentifythechanges tobe madeinthe

questionnaire

Helps intime savingin main survey


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Limitations of pilot survey

Only possibleon small population

Mayledto wrong predictions

Thedatacollectedcannotbe usedfor main survey

Same participants shouldnotbe usedinthe main

survey

If pilot studyis unsuccessful, theninvestigator may

drop a main survey


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Scrutinyand Editingofdata

Thedatacollectedneeds tobe scrutinizedfor

reliabilityandneeds editingbasedonthe scrutiny

Points of scrutiny:

1.Legibility

2.Completeness

3.Consistency

Unit 2 - Statistical Survey

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