RESEARCH DESIGN AK Dhamija
RESEARCH DESIGN
Definition Classification Exploratory Research Descriptive Research Causal Research Relationships Among Exploratory, Descriptive,
and Causal Research Threats to Internal & External Validity Overcoming Threats
Definition Classification Exploratory Research Descriptive Research Causal Research Relationships Among Exploratory, Descriptive,
and Causal Research Threats to Internal & External Validity Overcoming Threats
DEFINITION
A research design is a blueprint for conductingthe research project.
It details the procedures for obtaining theinformation needed to solve the researchproblems.
A research design is a blueprint for conductingthe research project.
It details the procedures for obtaining theinformation needed to solve the researchproblems.
COMPONENTS OF RESEARCH DESIGN
Information needed Design the exploratory, descriptive, and/or causal
phases of the research Specify the measurement and scaling procedures Construct and pretest a questionnaire Specify the sampling process and sample size Develop a plan of data analysis
Information needed Design the exploratory, descriptive, and/or causal
phases of the research Specify the measurement and scaling procedures Construct and pretest a questionnaire Specify the sampling process and sample size Develop a plan of data analysis
CLASSIFICATION OF RESEARCH DESIGN
Research Design
ConclusiveResearch Design
ExploratoryResearch Design
Single Cross-Sectional Design
Multiple Cross-Sectional Design
DescriptiveResearch
CausalResearch
Cross-SectionalDesign
LongitudinalDesign
BASIC RESEARCH DESIGNS
Objective:
Characteristics:
Methods:
Discovery of ideasand insights
Flexible, versatile
Often the front endof total researchdesign
Expert surveysPilot surveysSecondary data:qualitativeanalysisQualitativeresearch
Describe marketcharacteristics orfunctions
Marked by the priorformulation of specifichypotheses
Preplanned andstructured design
Secondary data:quantitative analysisSurveysPanelsObservation and otherdata
Determine causeand effectrelationships
Manipulation ofone or moreindependentvariables
Control of othermediatingvariables
Experiments
Exploratory Descriptive CausalObjective:
Characteristics:
Methods:
Discovery of ideasand insights
Flexible, versatile
Often the front endof total researchdesign
Expert surveysPilot surveysSecondary data:qualitativeanalysisQualitativeresearch
Describe marketcharacteristics orfunctions
Marked by the priorformulation of specifichypotheses
Preplanned andstructured design
Secondary data:quantitative analysisSurveysPanelsObservation and otherdata
Determine causeand effectrelationships
Manipulation ofone or moreindependentvariables
Control of othermediatingvariables
Experiments
ALTERNATIVE RESEARCH DESIGNS
Exploratory Research• Secondary DataAnalysis
• Focus Groups
Conclusive Research•Descriptive/Causal
Conclusive Research•Descriptive/Causal
(a)
(b) Conclusive Research•Descriptive/Causal
Exploratory Research• Secondary DataAnalysis
• Focus Groups
Conclusive Research•Descriptive/Causal
(b)
(c)
POTENTIAL SOURCES OF ERROR INRESEARCH DESIGNS
Total Error
Non-samplingError
RandomSampling Error
Non-responseError
ResponseError
Surrogate Information ErrorMeasurement ErrorPopulation Definition ErrorSampling Frame ErrorData Analysis Error
Respondent Selection ErrorQuestioning ErrorRecording ErrorCheating Error
Inability ErrorUnwillingness Error
Non-responseError
ResponseError
InterviewerError
RespondentError
ResearcherError
PRIMARY AND SECONDARY DATA
Primary Data Secondary Data
Collection purpose For the problem at hand For other problemsCollection process Very involved Rapid & easyCollection cost High Relatively lowCollection time Long Short
USE OF SECONDARY DATA
Identify the problem Better define the problem Develop an approach to the problem Formulate an appropriate research design (for
example, by identifying the key variables) Answer certain research questions and test some
hypotheses Interpret primary data more insightfully
Identify the problem Better define the problem Develop an approach to the problem Formulate an appropriate research design (for
example, by identifying the key variables) Answer certain research questions and test some
hypotheses Interpret primary data more insightfully
CRITERIA FOR EVALUATING SECONDARYDATA
Criteria Issues Remarks
Specifications& Methodology
Error &Accuracy
Currency
Objective
Nature
Dependability
Data collection method, responserate, quality & analysis of data,sampling technique & size,questionnaire design, fieldwork.Examine errors in approach,research design, sampling, datacollection & analysis, & reporting.
Time lag between collection &publication, frequency of updates.Why were the data collected?
Definition of key variables, units ofmeasurement, categories used,relationships examined.Expertise, credibility, reputation,and trustworthiness of the source.
Data should be reliable,valid, & generalizable tothe problem.
Assess accuracy bycomparing data fromdifferent sources.
Census data are updatedby syndicated firms.The objectivedetermines therelevance of data.Reconfigure the data toincrease theirusefulness.
Data should be obtainedfrom an original source.
Specifications& Methodology
Error &Accuracy
Currency
Objective
Nature
Dependability
Data collection method, responserate, quality & analysis of data,sampling technique & size,questionnaire design, fieldwork.Examine errors in approach,research design, sampling, datacollection & analysis, & reporting.
Time lag between collection &publication, frequency of updates.Why were the data collected?
Definition of key variables, units ofmeasurement, categories used,relationships examined.Expertise, credibility, reputation,and trustworthiness of the source.
Data should be reliable,valid, & generalizable tothe problem.
Assess accuracy bycomparing data fromdifferent sources.
Census data are updatedby syndicated firms.The objectivedetermines therelevance of data.Reconfigure the data toincrease theirusefulness.
Data should be obtainedfrom an original source.
CONDITIONS FOR CAUSALITY
Concomitant variation Time order of occurrence Absence of other possible causal factors
A set of procedures specifying:
the test units and how these units are to be dividedinto homogeneous subsamples,
what independent variables or treatments are to bemanipulated,
what dependent variables are to be measured; and
how the extraneous variables are to be controlled.
EXPERIMENTAL DESIGN
the test units and how these units are to be dividedinto homogeneous subsamples,
what independent variables or treatments are to bemanipulated,
what dependent variables are to be measured; and
how the extraneous variables are to be controlled.
VALIDITY IN EXPERIMENTATION
Internal validity
Establishing Cause and Effect relationship
Control of Extraneous Variables
External validity
Generalizability
To what populations, settings, times, independentvariables and dependent variables
Internal validity
Establishing Cause and Effect relationship
Control of Extraneous Variables
External validity
Generalizability
To what populations, settings, times, independentvariables and dependent variables
EXTRANEOUS VARIABLES History (H) : specific external events that occur at the same time as
the experiment. Maturation (MA) : changes in the test units themselves that occur
with the passage of time. Testing effects (T) : are caused by the process of experimentation. Main testing effect (MT) : occurs when a prior observation affects a
latter observation. Interactive testing effect (IT) : A prior measurement affects the
test unit's response to the independent variable. Instrumentation (I) : changes in the measuring instrument, in the
observers or in the scores themselves. Statistical regression effects (SR) : occur when test units with
extreme scores move closer to the average score during the course ofthe experiment.
Selection bias (SB) refers to the improper assignment of test unitsto treatment conditions.
Mortality (MO) refers to the loss of test units while the experimentis in progress.
History (H) : specific external events that occur at the same time asthe experiment.
Maturation (MA) : changes in the test units themselves that occurwith the passage of time.
Testing effects (T) : are caused by the process of experimentation. Main testing effect (MT) : occurs when a prior observation affects a
latter observation. Interactive testing effect (IT) : A prior measurement affects the
test unit's response to the independent variable. Instrumentation (I) : changes in the measuring instrument, in the
observers or in the scores themselves. Statistical regression effects (SR) : occur when test units with
extreme scores move closer to the average score during the course ofthe experiment.
Selection bias (SB) refers to the improper assignment of test unitsto treatment conditions.
Mortality (MO) refers to the loss of test units while the experimentis in progress.
CONTROLLING EXTRANEOUS VARIABLES
Randomization : The random assignment of testunits and treatment conditions to experimental groups
Matching involves comparing test units on a set ofkey background variables before assigning them to thetreatment conditions.
Statistical control involves measuring theextraneous variables and adjusting for their effectsthrough statistical analysis.
Design control involves the use of experimentsdesigned to control specific extraneous variables.
Randomization : The random assignment of testunits and treatment conditions to experimental groups
Matching involves comparing test units on a set ofkey background variables before assigning them to thetreatment conditions.
Statistical control involves measuring theextraneous variables and adjusting for their effectsthrough statistical analysis.
Design control involves the use of experimentsdesigned to control specific extraneous variables.
CLASSIFICATION OF EXPERIMENTALDESIGNS
Pre-experimental TrueExperimental
QuasiExperimental Statistical
RandomizedBlocks
Latin Square
FactorialDesign
Experimental Designs
One-Shot CaseStudy
One GroupPretest-Posttest
Static Group
Pretest-PosttestControl Group
Posttest: OnlyControl Group
Solomon Four-Group
Time Series
Multiple TimeSeries
RandomizedBlocks
Latin Square
FactorialDesign
VARIOUS PRE EXPERIMENTAL DESIGNS
One-Shot Case Study : X 01
More appropriate for exploratory study
One Group Pre-Post Test : 01 X 02
Treatment effect is computed as 02 – 01
Static Group Design:EG: X 01
CG: 02
Treatment effect is computed as 02 – 01
One-Shot Case Study : X 01
More appropriate for exploratory study
One Group Pre-Post Test : 01 X 02
Treatment effect is computed as 02 – 01
Static Group Design:EG: X 01
CG: 02
Treatment effect is computed as 02 – 01
VARIOUS TRUE EXPERIMENTAL DESIGNS
Pretest Posttest Control Group Design:
EG: R 01 X 02CG: R 03 04
02 – 01= TE + H + MA + MT + IT + I + SR + MO
04 – 03= H + MA + MT + I + SR + MO
Treatment effect(TE) = (02 - 01) - (04 - 03) = TE + IT
Selection Bias is eliminated by Randomization
Pretest Posttest Control Group Design:
EG: R 01 X 02CG: R 03 04
02 – 01= TE + H + MA + MT + IT + I + SR + MO
04 – 03= H + MA + MT + I + SR + MO
Treatment effect(TE) = (02 - 01) - (04 - 03) = TE + IT
Selection Bias is eliminated by Randomization
VARIOUS TRUE EXPERIMENTAL DESIGNSPosttest Only Control Group Design:
EG: R X 01CG: R 02Treatment effect(TE) = (01 – 02)
Solomon‘s Four Group Six Study Design:
EG1: R 01 X 02 :: 02 - 01CG1: R 03 04 :: 04 - 03EG2: R X 05 :: 05 – 0.5(01 + 03)CG2: R 06 :: 06 – 0.5(01 + 03)02 – 01 = TE + H + MA + MT + IT + I + SR + MO04 – 03 = H + MA + MT + I + SR + MO
Highest on Internal & External validity
[05 -0.5(01 + 03)] - [06 -0.5(01 + 03)] = TE : EG2 vs CG2
[(02 - 01)] - [05 -0.5(01 + 03)] = IT : EG2 vs EG1
[(04 - 03)] - [06 -0.5(01 + 03)] = Total uncontrolled Factors : : CG1 vs CG2
Posttest Only Control Group Design:EG: R X 01CG: R 02Treatment effect(TE) = (01 – 02)
Solomon‘s Four Group Six Study Design:
EG1: R 01 X 02 :: 02 - 01CG1: R 03 04 :: 04 - 03EG2: R X 05 :: 05 – 0.5(01 + 03)CG2: R 06 :: 06 – 0.5(01 + 03)02 – 01 = TE + H + MA + MT + IT + I + SR + MO04 – 03 = H + MA + MT + I + SR + MO
Highest on Internal & External validity
[05 -0.5(01 + 03)] - [06 -0.5(01 + 03)] = TE : EG2 vs CG2
[(02 - 01)] - [05 -0.5(01 + 03)] = IT : EG2 vs EG1
[(04 - 03)] - [06 -0.5(01 + 03)] = Total uncontrolled Factors : : CG1 vs CG2
QUASI EXPERIMENTAL DESIGNS
Time Series Design01 02 03 04 05 X 06 07 08 09 010
No randomization of test units to treatments.
The timing of treatment presentation, as well aswhich test units are exposed to the treatment, maynot be within the researcher's control.
Time Series Design01 02 03 04 05 X 06 07 08 09 010
No randomization of test units to treatments.
The timing of treatment presentation, as well aswhich test units are exposed to the treatment, maynot be within the researcher's control.
STATISTICAL DESIGNS
The effects of more than one independentvariable can be measured.
Specific extraneous variables can be statisticallycontrolled.
Economical designs can be formulated when eachtest unit is measured more than once.
The effects of more than one independentvariable can be measured.
Specific extraneous variables can be statisticallycontrolled.
Economical designs can be formulated when eachtest unit is measured more than once.
STATISTICAL DESIGNS - RCBRandomized Block Design(RCB) : Blocking ensuresclose matching of groups on external variable
Treatment GroupsBlock Store Commercial Commercial CommercialNumber Patronage A B C
1 Heavy A B C2 Medium A B C3 Low A B C4 None A B C
Treatment GroupsBlock Store Commercial Commercial CommercialNumber Patronage A B C
1 Heavy A B C2 Medium A B C3 Low A B C4 None A B C
STATISTICAL DESIGNS - LSDLatin Square Design: Statistically control two noninteracting external variables as well as tomanipulate the independent variable.Assignment rule is that each level of theindependent variable should appear only once ineach row and each column
Latin Square Design: Statistically control two noninteracting external variables as well as tomanipulate the independent variable.Assignment rule is that each level of theindependent variable should appear only once ineach row and each column
Interest in the StoreStore Patronage High Medium Low
Heavy B A CMedium C B ALow and none A C B
STATISTICAL DESIGNS - FDFactorial Design: To measure the effects of two or
more independent variables at various levels.
All the factors of all the levels are crossedSo many interactions : unwieldy but moreinformative
Amount of HumorAmount of Store No Medium HighInformation Humor Humor HumorLow A B C
Medium D E F
High G H I
Amount of HumorAmount of Store No Medium HighInformation Humor Humor HumorLow A B C
Medium D E F
High G H I
LABORATORY VS FIELD EXPERIMENTS
Factor Laboratory FieldEnvironment Artificial RealisticControl High LowReactive Error High LowDemand Artifacts High LowInternal Validity High LowExternal Validity Low HighTime Short LongNumber of Units Small LargeEase of Implementation High LowCost Low High
Factor Laboratory FieldEnvironment Artificial RealisticControl High LowReactive Error High LowDemand Artifacts High LowInternal Validity High LowExternal Validity Low HighTime Short LongNumber of Units Small LargeEase of Implementation High LowCost Low High