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MEASUREMENT. Measurement. “If you can’t measure it, you can’t manage it.” Bob Donath, Consultant. Measurement. Selecting measurable phenomena. Developing a set of mapping rules. Applying the mapping rule to each phenomenon.
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Measurement “If you can’t measure it, you can’t manage it.” Bob Donath, Consultant
Measurement Selecting measurable phenomena Developing a set of mapping rules Applying the mapping rule to each phenomenon
What is to be measured?CONCEPTS/CONSTRUCTS/VARIABLES • Operational Definitions - Dimensions - Elements • Scales
CONCEPT A GENERALIZED IDEA ABOUT A CLASS OF OBJECTS, ATTRIBUTES, OCCURRENCES, OR PROCESSES. (e.g., Technology, Dynamism, Adoption, Learning)
CONSTRUCT • An image or idea specifically invented for a given research and/or theory-building purpose • Higher level concepts for specialised scientific explanatory purposes that are not directly observable and for thinking about and communicating abstractions Concepts and constructs are used at theoretical levels
VARIABLE • Used at empirical level • Accept numeral or values for the purpose of testing and measurement
OPERATIONAL DEFINITION A definition for a construct stated in terms of specific criteria for testing or measurement Specifies what the researcher must do to measure the concept/construct under investigation
SCALE- Definition • SERIES OF ITEMS • ARRANGED ACCORDING TO VALUE • FOR THE PURPOSE OF QUANTIFICATION • A CONTINUOUS SPECTRUM
SCALE PROPERTIES • UNIQUELY CLASSIFIES • PRESERVES ORDER • DISTANCE/EQUAL INTERVALS • NATURAL ORIGIN (ZERO)
Types of Scales Nominal Ordinal Interval Ratio
Nominal Scales • Mutually exclusive and collectively exhaustive categories • Exhibits the classification characteristic only
NOMINAL SCALE PROPERTIES UNIQUELY CLASSIFIES • Male/Female • Academic/Admin • Asian/European • Strategy types • Adopters/Non Adopters
Levels of Measurement Nominal Classification Ordinal Interval Ratio
Ordinal Scales • Characteristics of nominal scale plus an indication of order • Implies statement of greater than and less than
ORDINAL SCALE PROPERTIES UNIQUELY CLASSIFIES PRESERVES ORDER • Win, Place & Show • Podium/Grid positions • Ranking
Levels of Measurement Nominal Classification Ordinal Classification Order Interval Ratio
Interval Scales • Characteristics of nominal and ordinal scales plus the concept of equality of interval. • Equal distance exists between numbers
INTERVAL SCALE PROPERTIES UNIQUELY CLASSIFIES PRESERVES ORDER EQUAL INTERVALS • Consumer Price Index (Base 100) • Fahrenheit Temperature • Assessment of attitude, beliefs, intention
Levels of Measurement Nominal Classification Ordinal Classification Order interval Classification Distance Order Ratio
Ratio Scales • Characteristics of previous scales plus an absolute zero point • Examples • Weight • Height • Number of children
RATIO SCALE PROPERTIES UNIQUELY CLASSIFIES PRESERVES ORDER EQUAL INTERVALS NATURAL ZERO • Weight and distance • Age, years of service
Levels of Measurement Nominal Classification Ordinal Classification Order Interval Classification Distance Order Ratio Classification Distance Order Natural Origin
Goodness of Measures • Accurately measuring what actually the concept one sets out to measure • Should be easy and efficient to use
Validity Reliability Practicality Evaluating Measurement Tools Criteria
Validity The ability of a scale to measure what was intended to be measured.
Validity Determinants Content Criterion Construct
Increasing Content Validity Content Question Database Literature Search Expert Interviews Group Interviews
……Goodness of Measures • Validity • Content Validity • Includes Face Validity • How well the dimensions and elements of a concept have been delineated • Professional agreement that a scale logically appears to accurately measure what it is intended to measure
Validity Determinants Content Construct
Increasing Construct Validity New measure of trust Known measure of trust Empathy Credibility
……Goodness of Measures • Construct Validity – when empirical evidence generated by a measure is consistent with the theoretical logic of the concept • Convergent Validity – the measure should “converge” with other similar measures • Discriminant Validity – when the measure has low correlation with measures of dissimilar concept
Judging Criterion Validity Relevance Criterion Freedom from bias Reliability Availability
Criterion-Related Validity • Concurrent – When the scale discriminates individuals who are known to be different; A type of criterion validity whereby a new measure correlates with a criterion measure taken at the same time. • Predictive Validity – Ability to differentiate among individuals with reference to a future criterion
Reliability The degree to which measures are free from random error and therefore yield consistent results.
Reliability Estimates Stability Internal Consistency Equivalence
Reliability Estimates Stability Internal Consistency Equivalence
… Reliability • Stability of Measures • Test-Retest Reliability – the administering of the same scale or measure to the same respondents at two separate points in time • Parallel-Form Reliability - when responses on two comparable sets of measures tapping the same construct are highly correlated
Reliability Estimates Stability Internal Consistency Equivalence
Equivalence • Variations at one point in time among observers and samples of items
Reliability Estimates Stability Internal Consistency Equivalence
… Reliability • Internal Consistency Measures • Interitem Consistency Reliability - where items that are independent measures of the same concept correlate with one another. • Split-Half Reliability – reflects the correlations between two halves of an instrument
Practicality Economy Interpretability Convenience