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Slide 1

LIS 570

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

Slide 2

Summary

• Define concepts

• Identify dimensions

• Identify variables

• Identify indicators

• Evaluate the indicators

• Moving from the abstract and theoretical to the empirical and measurable

Slide 3

Descending the Ladder of Abstraction

• Problem statement

• Statement of Concepts

• Abstractions

• Not empirical

• Process of making empirical

• Operationalization (Bouma)

• Clarifying concepts (De Vaus)

Slide 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

Slide 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”

Slide 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

Slide 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?

Slide 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

Slide 9

Concepts and variables

• Operationalization

• finding measurable variables for concepts

• Operational definition

• defines a concept in empirical terms

Slide 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

Slide 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 organization

Slide 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?

Slide 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

Slide 14

Indicators

• How many indicators should we use?

• How do we develop indicators?

• Measures developed in previous studies

• observation, unstructured interviews

• informants

Slide 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

Slide 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

Slide 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

Slide 18

Levels of measurement

• 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

Slide 19

Levels of measurement

• 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

Slide 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

Slide 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

Slide 22

Summary - descending the ladder of abstraction