LIS 570

1. LIS 570 How can I measure that? Selecting Variables. Developing indicators for concepts

2. Summary • Define concepts • Identify dimensions • Identify variables • Identify indicators • Evaluate the indicators Moving from the abstract and theoretical to the empirical and measurable

3. Descending the Ladder of Abstraction • Problem statement • Statement of Concepts • Abstractions • Not empirical • Process of making empirical • Operationalization (Bouma) • Clarifying concepts (De Vaus)

4. Descending the Ladder of Abstraction • Process • Develop a conceptual definition for the concept(s) • locate a range of definitions • select one for the study • Find variables for the concept • Assess validity of variables

5. Develop a Conceptual Definition • Conceptual definition • “Dictionary type definition” • Consists of more concepts • Leisure Activities of Interest“activities-apart from obligation to work, family & society to which a person turns at will” • “interests = those activities which people actively seek out”

6. Locate and select a definition • Locate a range of definitions • everyday definitions • scholarly definitions • Select one definition • Useful • Appropriate • Relevant • Necessary to measure validity

7. Delineate the dimensions of the concept • Many concepts have a number of different aspects or dimensions • should be distinguished • we may use one of these dimensions in the study • we may develop indicators for each dimension • E.g. What are the dimensions of leisure activity?

8. Conceptual definitions • Importance of definition • Determines type(s) of data • Clarifies meaning for researchers, participants and readers • “interests” = “likes and dislikes” • leisure = “non-utilitarian activities

9. Concepts and variables • Operationalization • finding measurable variables for concepts • Operational definition • defines a concept in empirical terms How can I measure that?

10. Find Variables for the concept • Definition • Concept which varies in type or amount • Gender varies in type • Male or female • Time spent engaging in leisure activities varies in amount • Concept which is measurable • Concept to which values have been assigned. • Values must be - exhaustive; exclusive

11. Variables • For most concepts there will be many variables • Leisure Activities of interest • Different types of Activities: • Engages in boxing • Engages in cooking • Amount of time engaging in leisure • Location of activity • Level of organisation

12. Indicators • Indicators become the focus of questions asked and evidence gathered • An empirical observation that can be taken as evidence of particular attributes of a variable • eg male or female is an indicator of gender • Marital status? • Educational level?

13. Indicators • To study the compassion of LIS570 students“a feeling of deep sorrow for living things stricken by misfortune” “a strong desire to alleviate the pain of living things” • indicators • cry when people die in movies • vomit at motor accidents • feel sad when the local possum stops coming for food

14. Indicators • How many indicators should we use? • How do we develop indicators? • Measures developed in previous studies • observation, unstructured interviews • informants

15. Evaluating indicators • Validity • the indicators measure the concept that we think they are measuring • appropriateness and relevance of the indicators • eg is educational level a valid indicator of social status? • reliability • we can rely on the answers that people give to the questions that we ask

16. Levels of measurement • Any variable is composed of 2 or more categories or attributes • eg sex (male/ female); country of birth (Australia, USA, NZ etc) • Level of measurement refers to how the categories of the variable relate to one another

17. Levels of measurement • Nominal - measuring a variable at this level involves naming the calibration units • (1) = Male  Value Label • (2) = Female  Value Label • Sample data: 2 2 1 1 2 2 1 1

18. Ordinal - involves arranging the calibration units into a logical order of rank Age (number of years) (1) 18-24 (2) 25-31 (3) 32-38 (4) 39-45 There is an order in the calibrations without any assumption that the distances between each calibrating unit are equal Levels of measurement

19. Interval e.g.Number of hours; Values designate quantity; 2 more than 1 less than 3; Person 2 has more of the characteristic number of hours exercising (5 hours) than person 1 (2 hours); Difference between them is 3 hours Has order but also involves specifying an equal distance between each successive unit Levels of measurement

20. Levels of measurement • Ratio • specifies a distance between each successive calibration • assumes there is a point at which the variable literally does not exist eg height and weight

21. Which level to aim for (De Vaus) • Interval or ratio levels • precise averages can be calculated • ie what is the average sex of students at UW? • More powerful and sophisticated techniques of analysis are available • higher levels of measurement provide more information • interval level measures can be converted to ordinal or nominal level but not vice versa

22. Summary - descending the ladder of abstraction Concept Dimensions Variables Indicators Validity & Reliability