Concepts to be included (in)direct observable Conceptualization Construct Scale Reliability Index (Measurement) Validity (and its reverse: data collection bias) Typology Operationalization Indicator Measurement

indices, typologies and scales Henk van der Kolk

Aim Measuring ‘theoretical constructs’ Conceptualization operationalization measurement Constructing indices, typologies and scales

Example

Theoretical variable(s) Two aspects of observation RQ: ‘What are the mathematical abilities of students at this university’ Theoretical variable(s) Conceptualization Operationalization Measurement Sampling Unit (s) Data

Observables and constructs Some ‘theoretical variables’ are relatively simple: (direct or indirect) observables Example: gender, age … Other ‘theoretical variables’ are complex, consisting of various dimensions or aspects: constructs

Examples of Constructs (Being a) bachelor (not married, male, above 18) (level of) democracy (level of) centralization IQ mathematical abilities

Conceptualization (def.) Making clear what you mean with the theoretical construct, its possible dimensions or aspects, and its attributes (values) Hier moet nog iets veranderd worden? Vanwege de (def.)

Example Mathematical abilities, with various ‘aspects’ To add (+), subtract (-), multiply (x), divide (∕), exponantiationthis, to find the root

Operationalization (def.) The construction of the exact procedures (in the context of some data collection method) to be used for data collection. Example: Formulating specific questions (items, indicators) measuring mathematical abilities. Wederom (def.)

Content validity If all aspects of a construct are included in the operationalization; ‘content validity’ Example: Mathematical abilities: include not only addition and multiplication!

Combining indicators into one construct Three ways to combining indicators: Index Typology Scale Example: using answers to 60 mathematical questions

Index Creating an ordinal variable by simply ‘adding up’ answers Example: Number of correct answers (between 0 and 60)

Typology Creating a nominal variable, by using the intersection of two or more ‘variables’. Example: Correct answers to ‘adding’ (10 items) Correct answers to ‘multiplication’ (10 items)

Typology Able to add Type 2 Only add specialists Type 3 Mathematical sophicated Not able to multiply Able to multiply Type 1 Mathematical unsophicated Type 4 Only multiply specialists Not able to add

Scale Creating an ordinal variable by combining answers (as in an index), after checking the empirical relationships between the answers and sometimes by taking into account these relationships

(Guttman) Scale Able to add Type 2 Only adding Type 3 Mathematical sophicated Not able to multiply Able to multiply Type 1 Mathematical unsophicated Type 4 “maybe there is no-one in this category” Not able to add

Scaling The idea of scaling is far more sophisticated than can be explained here Different types of structures and assumptions …. It may help to assessing the ‘reliability’ of a measured construct (wellicht alleen gesproken, niet in een slide) …

This micro lecture Measuring ‘theoretical constructs’ Conceptualization Operationalization Measurement Constructing indices, typologies and scales De opsomming in het midden heb ik bulletpoints van gemaakt. Aan jou of dit ook echt beter is.

Images used Slide 4: https://pixabay.com/nl/wiskunde-formule-natuurkunde-school-757566/ Slide 9: https://pixabay.com/nl/formule-wiskunde-natuurkunde-594149/ Slide 13: https://pixabay.com/nl/accepteren-ja-vinkje-symbool-47587/