1 Measurement Measurement Rules

2 Measurement Components CONCEPTUALIZATION CONCEPTUALIZATION NOMINAL DEFINITION NOMINAL DEFINITION OPERATIONAL DEFINITION OPERATIONAL DEFINITION MEASUREMENT OF THE ATTRIBUTES MEASUREMENT OF THE ATTRIBUTES

3 Measurement Quality RELIABILITY – consistency RELIABILITY – consistency VALIDITY – “on target” VALIDITY – “on target”

4 Reliability TEST-RETEST TEST-RETEST SPLIT-HALF SPLIT-HALF ESTABLISHED MEASURES ESTABLISHED MEASURES RESEARCHER-WORKER RESEARCHER-WORKER

5 Validity FACE FACE CRITERION (predictive) - uses behavior CRITERION (predictive) - uses behavior CONSTRUCT - uses theoretical connection CONSTRUCT - uses theoretical connection CONTENT - multiple attributes for complex concepts CONTENT - multiple attributes for complex concepts

6 Rules (Levels) of Measurement Nominal Nominal Mutually exclusive and exhaustive Mutually exclusive and exhaustive Ordinal Ordinal First to last/High to low First to last/High to low Interval Interval Known distance between attributes Known distance between attributes Ratio Ratio Absolute zero Absolute zero

7 Measurement Matrix Mutually Exclusive & Exhaustive Inherent order or Sequence Known distance between attributes Absolute Zero Nominal X Ordinal X X Interval X X X Ratio X X X X

8 Measurement in the Social Sciences OBSERVATION – the systematic process of recording the behavioral patterns of people, objects, and occurrences without questioning or communicating with them OBSERVATION – the systematic process of recording the behavioral patterns of people, objects, and occurrences without questioning or communicating with them QUESTONING – the systematic process of interacting with people directly and/or indirectly in order to have them respond to statements and/or questions QUESTONING – the systematic process of interacting with people directly and/or indirectly in order to have them respond to statements and/or questions

9 Prior Questions SHOULD YOU DO THE STUDY? SHOULD YOU DO THE STUDY? WHO WILL USE THE DATA? WHO WILL USE THE DATA? HOW WILL THE DATA BE USED? HOW WILL THE DATA BE USED? WHAT DATA NEED TO BE COLLECTED? WHAT DATA NEED TO BE COLLECTED? WHO WILL SUPPLY THE DATA? WHO WILL SUPPLY THE DATA? HOW WILL THE DATA BE ANALYZED? HOW WILL THE DATA BE ANALYZED?

10 MEASUREMENT IDEAS INTERVIEW POTENTIAL USERS INTERVIEW POTENTIAL USERS REVIEW LITERATURE REVIEW LITERATURE INTERVIEW SAMPLE OF RESPONDENTS INTERVIEW SAMPLE OF RESPONDENTS BRAIN-STORMING BRAIN-STORMING

11 What can we observe? Human behavior and physical actions and evidence Human behavior and physical actions and evidence Verbal behavior Verbal behavior Spatial relations and locations Spatial relations and locations Temporal patterns Temporal patterns Physical objects Physical objects Verbal and pictorial records Verbal and pictorial records Expressive behavior Expressive behavior

12 Trace Evidence Erosion Erosion Accretion Accretion

13 How do we Question? Directly by researcher Directly by researcher Interview Interview Indirectly by researcher Indirectly by researcher Questionnaire Questionnaire

14 CRITERIA FOR QUESTIONS CLARITY CLARITY LENGTH LENGTH SPECIFICITY SPECIFICITY UNIDIMENSIONALITY UNIDIMENSIONALITY WORD CHOICE WORD CHOICE

15 Criteria for Questions (cont) BIAS BIAS SENSITIVITY SENSITIVITY REDUNDANCY REDUNDANCY PURPOSEFULNESS PURPOSEFULNESS OMNISCIENCE OMNISCIENCE

16 THE RESPONSES: Open-Ended PILOT STUDIES PILOT STUDIES LESS BIASED LESS BIASED VARIETY OF RESPONSES VARIETY OF RESPONSES INTRODUCE NEW TOPICS INTRODUCE NEW TOPICS RESPONDENTS “HAVE THEIR SAY” RESPONDENTS “HAVE THEIR SAY” BACKGROUND FOR INTERPRETATION BACKGROUND FOR INTERPRETATION “LIFE & CREDIBILITY” “LIFE & CREDIBILITY”

17 THE RESPONSES: Fixed-choice UNIFORM STIMULI UNIFORM STIMULI EASY & QUICK TABULATION EASY & QUICK TABULATION NOT DEPENDENT UPON WRITING ABILITY OF RESPONDENTS NOT DEPENDENT UPON WRITING ABILITY OF RESPONDENTS LESSEN PROBLEMS OF VOCABULARY LESSEN PROBLEMS OF VOCABULARY MORE QUESTIONS ASKED MORE QUESTIONS ASKED EASIER FOR PEOPLE TO COMPLETE EASIER FOR PEOPLE TO COMPLETE

18 What do we do with the data? Review Review Record Record Develop composite measures Develop composite measures

19 Composite Measures Indexes Indexes Scales Scales Typologies Typologies

20 Built Scores Index and Scales Index and Scales Both are Ordinal – scores are relative and provide a “ranking” of subjects Both are Ordinal – scores are relative and provide a “ranking” of subjects Both are “Composite” measures – built by “combining values” for several measures Both are “Composite” measures – built by “combining values” for several measures

21 Index Index is constructed by accumulating scores assigned to individuals Index is constructed by accumulating scores assigned to individuals e.g. “add up” the number of scores on a set of measures i.e. count the number of “yes” responses on a set of measures

22 Index construction Select the items – face validity, uni- dimensionality, general or specific, variance Select the items – face validity, uni- dimensionality, general or specific, variance Examine the empirical relationships among the items – bi-variate, multivariate Examine the empirical relationships among the items – bi-variate, multivariate Assign the scores to the items Assign the scores to the items Manage missing data – exclude cases, missing as a response, substitution Manage missing data – exclude cases, missing as a response, substitution Validation – item analysis, external validation Validation – item analysis, external validation

23 Scale Constructed by assigning “scores” to patterns of responses – recognizing that some items reflect a relatively “weak degree” of the variable while others reflect something “stronger” Constructed by assigning “scores” to patterns of responses – recognizing that some items reflect a relatively “weak degree” of the variable while others reflect something “stronger” e.g. “women different than men” is relatively weaker on a “sexism scale” than “men should be given preference in jobs over women”

24 Scale Construction Scales offer more assurance of ordinality by “getting at” the intensity structure among the indicators – there are a number of methods for “scaling” Scales offer more assurance of ordinality by “getting at” the intensity structure among the indicators – there are a number of methods for “scaling” Bogardus Social Distance Scale – (logical structure) Bogardus Social Distance Scale – (logical structure) Thurstone Scales – (uses judges) Thurstone Scales – (uses judges) Likert Scales – (differences in intensity) Likert Scales – (differences in intensity) Semantic Differential – (opposites) Semantic Differential – (opposites) Guttman Scaling – (“hard vs easy”) Guttman Scaling – (“hard vs easy”)

25 Typology Used to summarize the “intersection” of two or more variables (matrix) thus creating a “new variable” Used to summarize the “intersection” of two or more variables (matrix) thus creating a “new variable”

26 Transient Housing Typology TEMPORAL vs vs CHOICE CHOICEOpportunityNecessity Temporary Temporary Opportunists Temporary Necessitarians Permanent Permanent Opportunists Permanent Necessitaritans