SlideShare ist ein Scribd-Unternehmen logo
1 von 21
Downloaden Sie, um offline zu lesen
CORRELATIONAL RESEARCH
QUANTITATIVE RESEARCH
METHODOLOGIES
Presented By: Manoj Patel
Asst. Professor
JHUNJHUNWALA BUSINESS SCHOOL
THE NATURE OF
CORRELATIONAL RESEARCH
• Sometimes called associational research
• It investigates the possibility of relationships
between only two variables
• Also sometimes referred to as a form of
descriptive research
• Describes the degree to which two or more
quantitative variables are related
PURPOSES OF CORRELATIONAL
RESEARCH
• Two basic purposes
1. Help explain important human behaviors
(Explanatory Studies)
2. Predict likely outcomes
(Prediction Studies)
EXPLANOTARY STUDIES
• Researchers often investigate a number of
variables they believe are related to a more
complex variable.
• Unrelated variables dropped from further
consideration
• Most researchers most probably trying to
gain some ideas about cause and effect
• However it does not establish cause and
effect
PREDICTION STUDIES
• Predict a score on one variable if a score on
the other variable is known
• Determine the predictive validity of
measuring instruments
• Predictor Variable; variable that is used to
make the prediction
• Criterion Variable; variable about which the
prediction is made
Using Scatter plots to Predict a Score
• We can use the scatter plots to find a
correlation between the variables
• correlational research.pptx
A simple Prediction Equation
• Used to express the regression line
• We gain confidence in using the
prediction equation to make future
predictions if there is a close similarity
between two results
'Y
MORE COMPLEX
CORRELATIONAL TECHNIQUES
1. Multiple Regressions; technique that
enables researchers to determine a
correlation between a criterion variable
• The best combination of two or more
predictor variables
2. The Coefficient of Multiple Correlation
• Symbolized by R; indicates the strength of
the correlation between the combination of
the predictor variables and the criterion
variables.
• multiple correlation.jpg
• The higher R is, the more reliable a
prediction will be
3. The Coefficient of Determination
• The square of the correlation between a
predictor and a criterion variable
• Indicates the percentage of the variability
among the criterion scores that can be
attributed to differences in the scores on
the predictor variable
4. Discriminant Function Analysis
• Technique used when the technique of
multiple regression cannot be used when
the criterion variable is categorical
5. Factor Analysis
• Technique that allows a researcher to
determine if many variables can be
described by a few factors.
BASIC STEPS IN
CORRELATIONAL RESEARCH
1. Problem Selection
• Three major types of problems;
a. is variable X related to variable Y?
b. how well does variable P predict variable C?
c. What are the relationship among a large
number of variables and what predictions can
be made?
2. Sample
• Should be selected carefully, and if
possible, randomly.
• Not less than 30.
3. Instruments
• Most correlational studies involve the
administration of some types of
instruments (tests, questionnaire, and so
on).
4. Design and Procedures
• Design used quite straightforward.
5. Data Collection
• Data on both variables will usually be
collected in a short time.
• Instruments used are administered in a
single session or two sessions
THREATS TO INTERNAL
VALIDITY
• There are some threats identified in
conducting correlational research
1. Subject Characteristics
• Individuals or groups have two or more
characteristics; might be a cause of
variation in the other two variables.
2. Location
• Location is different for different subject
• One location may be more comfortable
compared to others
3. Instrumentation
• Instrument decay; care must be taken to ensure
the observers don’t become tired, bored or
inattentive
• Data collector characteristics; different gender,
age or ethnicity may affect specific response
4. Testing
• Experience of responding to the first
instrument may influence subject responses
to the second instrument
5. Mortality
• Loss of subjects may make a relationship
more (or less) likely in the remaining data
EVALUATING THREATS TO
INTERNAL VALIDITY
• Follows a procedure similar to the
experimental research.
1. Subject Characteristics
• Four of many possible characteristics
a. Severity of disability
b. Socioeconomic level of parents
c. Physical strength and coordination
d. Physical appearance
2. Mortality
• Loss of subjects can be expected to reduce
magnitude of correlation
3. Location
• Threats could be controlled by
independently assessing the job-site
environments.
4. Instrumentation
• Instrument decay; observations should
scheduled
• Data collector characteristics; interaction of
data collectors and supervisors is a
necessary parts
• Data collector bias; observers should have
no knowledge of job ratings
Quantitative research methodologies  correlational research

Weitere ähnliche Inhalte

Was ist angesagt?

Subjective test (Essay)
Subjective test (Essay) Subjective test (Essay)
Subjective test (Essay)
Widya' Amnezhia
 
Qualitative data analysis - Martyn Hammersley
Qualitative data analysis - Martyn HammersleyQualitative data analysis - Martyn Hammersley
Qualitative data analysis - Martyn Hammersley
OUmethods
 
Mixed methods research
Mixed methods researchMixed methods research
Mixed methods research
Khalid Mahmood
 
Correlational research
Correlational researchCorrelational research
Correlational research
Azura Zaki
 
Developing Assessment Instruments Chapter 7
Developing Assessment Instruments Chapter 7Developing Assessment Instruments Chapter 7
Developing Assessment Instruments Chapter 7
cdjhaigler
 
Causal comparative research
Causal comparative researchCausal comparative research
Causal comparative research
Noor Hasmida
 

Was ist angesagt? (20)

Point biserial correlation
Point biserial correlationPoint biserial correlation
Point biserial correlation
 
types of qualitative research
types of qualitative researchtypes of qualitative research
types of qualitative research
 
variable in research
variable in researchvariable in research
variable in research
 
Subjective test (Essay)
Subjective test (Essay) Subjective test (Essay)
Subjective test (Essay)
 
Experimental method of Research
Experimental method of ResearchExperimental method of Research
Experimental method of Research
 
Quantitative, qualitive and mixed research designs
Quantitative, qualitive and mixed research designsQuantitative, qualitive and mixed research designs
Quantitative, qualitive and mixed research designs
 
What is an experimental research (1)
What is an experimental research (1)What is an experimental research (1)
What is an experimental research (1)
 
Mixed methods research combined
Mixed methods research combinedMixed methods research combined
Mixed methods research combined
 
Relational and correlational research
Relational and correlational researchRelational and correlational research
Relational and correlational research
 
Qualitative data analysis - Martyn Hammersley
Qualitative data analysis - Martyn HammersleyQualitative data analysis - Martyn Hammersley
Qualitative data analysis - Martyn Hammersley
 
Mixed methods research
Mixed methods researchMixed methods research
Mixed methods research
 
Chapter 2: Ethical Principles of Research
Chapter 2: Ethical Principles of  Research Chapter 2: Ethical Principles of  Research
Chapter 2: Ethical Principles of Research
 
Correlational research
Correlational researchCorrelational research
Correlational research
 
Basic principles of research
Basic principles of researchBasic principles of research
Basic principles of research
 
Developing Assessment Instruments Chapter 7
Developing Assessment Instruments Chapter 7Developing Assessment Instruments Chapter 7
Developing Assessment Instruments Chapter 7
 
Case study method in research
Case study method in researchCase study method in research
Case study method in research
 
Data collection in quantitative research
Data collection in quantitative researchData collection in quantitative research
Data collection in quantitative research
 
Causal comparative research
Causal comparative researchCausal comparative research
Causal comparative research
 
Correlational research
Correlational researchCorrelational research
Correlational research
 
Qualitative research
Qualitative researchQualitative research
Qualitative research
 

Andere mochten auch

Quantitative designs
Quantitative designsQuantitative designs
Quantitative designs
Carla Piper
 
Grounded Theory and Design
Grounded Theory and DesignGrounded Theory and Design
Grounded Theory and Design
Mithat Konar
 
Receptive skills in english language teaching
Receptive skills in english language teachingReceptive skills in english language teaching
Receptive skills in english language teaching
Osnovna šola Pivka
 

Andere mochten auch (10)

Quantitative research methodologies
Quantitative research methodologiesQuantitative research methodologies
Quantitative research methodologies
 
Quantitative designs
Quantitative designsQuantitative designs
Quantitative designs
 
CORE: Quantitative Research Methodology: An Overview
CORE: Quantitative Research Methodology: An OverviewCORE: Quantitative Research Methodology: An Overview
CORE: Quantitative Research Methodology: An Overview
 
Grounded Theory and Design
Grounded Theory and DesignGrounded Theory and Design
Grounded Theory and Design
 
Quantitative research - Research Methodology - Manu Melwin Joy
Quantitative research - Research Methodology - Manu Melwin JoyQuantitative research - Research Methodology - Manu Melwin Joy
Quantitative research - Research Methodology - Manu Melwin Joy
 
Receptive skills in english language teaching
Receptive skills in english language teachingReceptive skills in english language teaching
Receptive skills in english language teaching
 
Quantitative Research: Surveys and Experiments
Quantitative Research: Surveys and ExperimentsQuantitative Research: Surveys and Experiments
Quantitative Research: Surveys and Experiments
 
Grounded theory
Grounded theoryGrounded theory
Grounded theory
 
Quantitative and Qualitative Research
Quantitative and Qualitative ResearchQuantitative and Qualitative Research
Quantitative and Qualitative Research
 
Sampling Methods in Qualitative and Quantitative Research
Sampling Methods in Qualitative and Quantitative ResearchSampling Methods in Qualitative and Quantitative Research
Sampling Methods in Qualitative and Quantitative Research
 

Ähnlich wie Quantitative research methodologies correlational research

Correlational research
Correlational researchCorrelational research
Correlational research
Dhiya Lara
 
Slide presentation
Slide presentationSlide presentation
Slide presentation
Neza Mohd
 
Correlational and Survey Research
Correlational and Survey ResearchCorrelational and Survey Research
Correlational and Survey Research
zuraiberahim
 
Slide presentation
Slide presentationSlide presentation
Slide presentation
zuraiberahim
 
Correlational n survey research
Correlational n survey researchCorrelational n survey research
Correlational n survey research
Noor Hasmida
 
Chapter 2 class version a
Chapter 2 class version aChapter 2 class version a
Chapter 2 class version a
jbnx
 
Development of health measurement scales - part 1
Development of health measurement scales - part 1Development of health measurement scales - part 1
Development of health measurement scales - part 1
Rizwan S A
 
Survey, correlational & ccr research (SHEHA GROUP)
Survey, correlational & ccr research (SHEHA GROUP)Survey, correlational & ccr research (SHEHA GROUP)
Survey, correlational & ccr research (SHEHA GROUP)
Sheha Shaida Tuan Hadzri
 
Survey Correlational Research
Survey Correlational ResearchSurvey Correlational Research
Survey Correlational Research
Azreen5520
 

Ähnlich wie Quantitative research methodologies correlational research (20)

Correlational research
Correlational researchCorrelational research
Correlational research
 
Slide presentation
Slide presentationSlide presentation
Slide presentation
 
Slide presentation
Slide presentationSlide presentation
Slide presentation
 
Correlational and Survey Research
Correlational and Survey ResearchCorrelational and Survey Research
Correlational and Survey Research
 
Slide presentation
Slide presentationSlide presentation
Slide presentation
 
Correlational n survey research
Correlational n survey researchCorrelational n survey research
Correlational n survey research
 
Module5_Quantitative_.pptx
Module5_Quantitative_.pptxModule5_Quantitative_.pptx
Module5_Quantitative_.pptx
 
Threats to validity
Threats to validityThreats to validity
Threats to validity
 
Criteria in social research
Criteria in social researchCriteria in social research
Criteria in social research
 
Quantitative Research Design.ppt
Quantitative Research Design.pptQuantitative Research Design.ppt
Quantitative Research Design.ppt
 
Introduction to research
Introduction to researchIntroduction to research
Introduction to research
 
Chapter 2 class version a
Chapter 2 class version aChapter 2 class version a
Chapter 2 class version a
 
Development of health measurement scales - part 1
Development of health measurement scales - part 1Development of health measurement scales - part 1
Development of health measurement scales - part 1
 
Survey, correlational & ccr research (SHEHA GROUP)
Survey, correlational & ccr research (SHEHA GROUP)Survey, correlational & ccr research (SHEHA GROUP)
Survey, correlational & ccr research (SHEHA GROUP)
 
Survey Correlational Research
Survey Correlational ResearchSurvey Correlational Research
Survey Correlational Research
 
Psychology 100 Research Design
Psychology 100 Research DesignPsychology 100 Research Design
Psychology 100 Research Design
 
Study designs & amp; trials presentation1 2
Study designs & amp; trials presentation1 2Study designs & amp; trials presentation1 2
Study designs & amp; trials presentation1 2
 
Reliability and validity
Reliability and  validityReliability and  validity
Reliability and validity
 
UPDATED-Quantitative-Methods for Prelims
UPDATED-Quantitative-Methods for PrelimsUPDATED-Quantitative-Methods for Prelims
UPDATED-Quantitative-Methods for Prelims
 
Research Methodology in Gait Analysis
Research Methodology in Gait AnalysisResearch Methodology in Gait Analysis
Research Methodology in Gait Analysis
 

Mehr von Research Scholar - HNB Garhwal Central University, Srinagar, Uttarakhand.

Mehr von Research Scholar - HNB Garhwal Central University, Srinagar, Uttarakhand. (20)

Sbi history and merger
Sbi history and mergerSbi history and merger
Sbi history and merger
 
Uint 2 learning (o.b)
Uint  2 learning (o.b)Uint  2 learning (o.b)
Uint 2 learning (o.b)
 
Tourism scope in India
Tourism scope in IndiaTourism scope in India
Tourism scope in India
 
OB Introduction, Scope, Challenges and Opportunities, goal and OB Model
OB Introduction, Scope, Challenges and Opportunities, goal and OB Model OB Introduction, Scope, Challenges and Opportunities, goal and OB Model
OB Introduction, Scope, Challenges and Opportunities, goal and OB Model
 
NOTES RETAIL AND DISTRIBUTION MANAGEMENT
NOTES RETAIL AND DISTRIBUTION MANAGEMENT NOTES RETAIL AND DISTRIBUTION MANAGEMENT
NOTES RETAIL AND DISTRIBUTION MANAGEMENT
 
NOTES RETAIL AND DISTRIBUTION MANAGEMENT
NOTES RETAIL AND DISTRIBUTION MANAGEMENT NOTES RETAIL AND DISTRIBUTION MANAGEMENT
NOTES RETAIL AND DISTRIBUTION MANAGEMENT
 
NOTES RETAIL AND DISTRIBUTION MANAGEMENT
NOTES RETAIL AND DISTRIBUTION MANAGEMENT NOTES RETAIL AND DISTRIBUTION MANAGEMENT
NOTES RETAIL AND DISTRIBUTION MANAGEMENT
 
NOTES RETAIL AND DISTRIBUTION MANAGEMENT
NOTES RETAIL AND DISTRIBUTION MANAGEMENT NOTES RETAIL AND DISTRIBUTION MANAGEMENT
NOTES RETAIL AND DISTRIBUTION MANAGEMENT
 
Liberalization, Privatization, Globalization
Liberalization, Privatization, Globalization Liberalization, Privatization, Globalization
Liberalization, Privatization, Globalization
 
Analysis of variance anova
Analysis of variance anovaAnalysis of variance anova
Analysis of variance anova
 
Industrial policy
Industrial policyIndustrial policy
Industrial policy
 
Type of economy
Type of economyType of economy
Type of economy
 
What is business environment
What is business environmentWhat is business environment
What is business environment
 
Business responsibility
Business responsibilityBusiness responsibility
Business responsibility
 
Notes unit ii
Notes unit iiNotes unit ii
Notes unit ii
 
Marketing environment.
Marketing environment.Marketing environment.
Marketing environment.
 
Indian business environment
Indian business environmentIndian business environment
Indian business environment
 
Technology Embalmed in Parle-G
Technology Embalmed in Parle-GTechnology Embalmed in Parle-G
Technology Embalmed in Parle-G
 
Unempolyement in India
Unempolyement in IndiaUnempolyement in India
Unempolyement in India
 
ECONOMIC TRENDS, Monetary policy of India,
ECONOMIC TRENDS, Monetary policy of India, ECONOMIC TRENDS, Monetary policy of India,
ECONOMIC TRENDS, Monetary policy of India,
 

Kürzlich hochgeladen

Kürzlich hochgeladen (20)

Scaling API-first – The story of a global engineering organization
Scaling API-first – The story of a global engineering organizationScaling API-first – The story of a global engineering organization
Scaling API-first – The story of a global engineering organization
 
Mastering MySQL Database Architecture: Deep Dive into MySQL Shell and MySQL R...
Mastering MySQL Database Architecture: Deep Dive into MySQL Shell and MySQL R...Mastering MySQL Database Architecture: Deep Dive into MySQL Shell and MySQL R...
Mastering MySQL Database Architecture: Deep Dive into MySQL Shell and MySQL R...
 
A Domino Admins Adventures (Engage 2024)
A Domino Admins Adventures (Engage 2024)A Domino Admins Adventures (Engage 2024)
A Domino Admins Adventures (Engage 2024)
 
A Year of the Servo Reboot: Where Are We Now?
A Year of the Servo Reboot: Where Are We Now?A Year of the Servo Reboot: Where Are We Now?
A Year of the Servo Reboot: Where Are We Now?
 
Data Cloud, More than a CDP by Matt Robison
Data Cloud, More than a CDP by Matt RobisonData Cloud, More than a CDP by Matt Robison
Data Cloud, More than a CDP by Matt Robison
 
Top 5 Benefits OF Using Muvi Live Paywall For Live Streams
Top 5 Benefits OF Using Muvi Live Paywall For Live StreamsTop 5 Benefits OF Using Muvi Live Paywall For Live Streams
Top 5 Benefits OF Using Muvi Live Paywall For Live Streams
 
Powerful Google developer tools for immediate impact! (2023-24 C)
Powerful Google developer tools for immediate impact! (2023-24 C)Powerful Google developer tools for immediate impact! (2023-24 C)
Powerful Google developer tools for immediate impact! (2023-24 C)
 
Understanding Discord NSFW Servers A Guide for Responsible Users.pdf
Understanding Discord NSFW Servers A Guide for Responsible Users.pdfUnderstanding Discord NSFW Servers A Guide for Responsible Users.pdf
Understanding Discord NSFW Servers A Guide for Responsible Users.pdf
 
Workshop - Best of Both Worlds_ Combine KG and Vector search for enhanced R...
Workshop - Best of Both Worlds_ Combine  KG and Vector search for  enhanced R...Workshop - Best of Both Worlds_ Combine  KG and Vector search for  enhanced R...
Workshop - Best of Both Worlds_ Combine KG and Vector search for enhanced R...
 
Real Time Object Detection Using Open CV
Real Time Object Detection Using Open CVReal Time Object Detection Using Open CV
Real Time Object Detection Using Open CV
 
Polkadot JAM Slides - Token2049 - By Dr. Gavin Wood
Polkadot JAM Slides - Token2049 - By Dr. Gavin WoodPolkadot JAM Slides - Token2049 - By Dr. Gavin Wood
Polkadot JAM Slides - Token2049 - By Dr. Gavin Wood
 
The 7 Things I Know About Cyber Security After 25 Years | April 2024
The 7 Things I Know About Cyber Security After 25 Years | April 2024The 7 Things I Know About Cyber Security After 25 Years | April 2024
The 7 Things I Know About Cyber Security After 25 Years | April 2024
 
Bajaj Allianz Life Insurance Company - Insurer Innovation Award 2024
Bajaj Allianz Life Insurance Company - Insurer Innovation Award 2024Bajaj Allianz Life Insurance Company - Insurer Innovation Award 2024
Bajaj Allianz Life Insurance Company - Insurer Innovation Award 2024
 
ProductAnonymous-April2024-WinProductDiscovery-MelissaKlemke
ProductAnonymous-April2024-WinProductDiscovery-MelissaKlemkeProductAnonymous-April2024-WinProductDiscovery-MelissaKlemke
ProductAnonymous-April2024-WinProductDiscovery-MelissaKlemke
 
Apidays New York 2024 - Scaling API-first by Ian Reasor and Radu Cotescu, Adobe
Apidays New York 2024 - Scaling API-first by Ian Reasor and Radu Cotescu, AdobeApidays New York 2024 - Scaling API-first by Ian Reasor and Radu Cotescu, Adobe
Apidays New York 2024 - Scaling API-first by Ian Reasor and Radu Cotescu, Adobe
 
2024: Domino Containers - The Next Step. News from the Domino Container commu...
2024: Domino Containers - The Next Step. News from the Domino Container commu...2024: Domino Containers - The Next Step. News from the Domino Container commu...
2024: Domino Containers - The Next Step. News from the Domino Container commu...
 
AWS Community Day CPH - Three problems of Terraform
AWS Community Day CPH - Three problems of TerraformAWS Community Day CPH - Three problems of Terraform
AWS Community Day CPH - Three problems of Terraform
 
MINDCTI Revenue Release Quarter One 2024
MINDCTI Revenue Release Quarter One 2024MINDCTI Revenue Release Quarter One 2024
MINDCTI Revenue Release Quarter One 2024
 
HTML Injection Attacks: Impact and Mitigation Strategies
HTML Injection Attacks: Impact and Mitigation StrategiesHTML Injection Attacks: Impact and Mitigation Strategies
HTML Injection Attacks: Impact and Mitigation Strategies
 
TrustArc Webinar - Stay Ahead of US State Data Privacy Law Developments
TrustArc Webinar - Stay Ahead of US State Data Privacy Law DevelopmentsTrustArc Webinar - Stay Ahead of US State Data Privacy Law Developments
TrustArc Webinar - Stay Ahead of US State Data Privacy Law Developments
 

Quantitative research methodologies correlational research

  • 1. CORRELATIONAL RESEARCH QUANTITATIVE RESEARCH METHODOLOGIES Presented By: Manoj Patel Asst. Professor JHUNJHUNWALA BUSINESS SCHOOL
  • 2. THE NATURE OF CORRELATIONAL RESEARCH • Sometimes called associational research • It investigates the possibility of relationships between only two variables • Also sometimes referred to as a form of descriptive research • Describes the degree to which two or more quantitative variables are related
  • 3. PURPOSES OF CORRELATIONAL RESEARCH • Two basic purposes 1. Help explain important human behaviors (Explanatory Studies) 2. Predict likely outcomes (Prediction Studies)
  • 4. EXPLANOTARY STUDIES • Researchers often investigate a number of variables they believe are related to a more complex variable. • Unrelated variables dropped from further consideration • Most researchers most probably trying to gain some ideas about cause and effect • However it does not establish cause and effect
  • 5. PREDICTION STUDIES • Predict a score on one variable if a score on the other variable is known • Determine the predictive validity of measuring instruments • Predictor Variable; variable that is used to make the prediction • Criterion Variable; variable about which the prediction is made
  • 6. Using Scatter plots to Predict a Score • We can use the scatter plots to find a correlation between the variables • correlational research.pptx
  • 7. A simple Prediction Equation • Used to express the regression line • We gain confidence in using the prediction equation to make future predictions if there is a close similarity between two results 'Y
  • 8. MORE COMPLEX CORRELATIONAL TECHNIQUES 1. Multiple Regressions; technique that enables researchers to determine a correlation between a criterion variable • The best combination of two or more predictor variables
  • 9. 2. The Coefficient of Multiple Correlation • Symbolized by R; indicates the strength of the correlation between the combination of the predictor variables and the criterion variables. • multiple correlation.jpg • The higher R is, the more reliable a prediction will be
  • 10. 3. The Coefficient of Determination • The square of the correlation between a predictor and a criterion variable • Indicates the percentage of the variability among the criterion scores that can be attributed to differences in the scores on the predictor variable
  • 11. 4. Discriminant Function Analysis • Technique used when the technique of multiple regression cannot be used when the criterion variable is categorical 5. Factor Analysis • Technique that allows a researcher to determine if many variables can be described by a few factors.
  • 12. BASIC STEPS IN CORRELATIONAL RESEARCH 1. Problem Selection • Three major types of problems; a. is variable X related to variable Y? b. how well does variable P predict variable C? c. What are the relationship among a large number of variables and what predictions can be made?
  • 13. 2. Sample • Should be selected carefully, and if possible, randomly. • Not less than 30. 3. Instruments • Most correlational studies involve the administration of some types of instruments (tests, questionnaire, and so on).
  • 14. 4. Design and Procedures • Design used quite straightforward. 5. Data Collection • Data on both variables will usually be collected in a short time. • Instruments used are administered in a single session or two sessions
  • 15. THREATS TO INTERNAL VALIDITY • There are some threats identified in conducting correlational research 1. Subject Characteristics • Individuals or groups have two or more characteristics; might be a cause of variation in the other two variables.
  • 16. 2. Location • Location is different for different subject • One location may be more comfortable compared to others 3. Instrumentation • Instrument decay; care must be taken to ensure the observers don’t become tired, bored or inattentive • Data collector characteristics; different gender, age or ethnicity may affect specific response
  • 17. 4. Testing • Experience of responding to the first instrument may influence subject responses to the second instrument 5. Mortality • Loss of subjects may make a relationship more (or less) likely in the remaining data
  • 18. EVALUATING THREATS TO INTERNAL VALIDITY • Follows a procedure similar to the experimental research. 1. Subject Characteristics • Four of many possible characteristics a. Severity of disability b. Socioeconomic level of parents c. Physical strength and coordination d. Physical appearance
  • 19. 2. Mortality • Loss of subjects can be expected to reduce magnitude of correlation 3. Location • Threats could be controlled by independently assessing the job-site environments.
  • 20. 4. Instrumentation • Instrument decay; observations should scheduled • Data collector characteristics; interaction of data collectors and supervisors is a necessary parts • Data collector bias; observers should have no knowledge of job ratings