Understanding Measurement in Social Sciences: Concepts, Operationalization, and Validity

1. Chapter 4: Concepts, Operationalization, & Measurement

2. Introduction • Social sciences – measurement is usually used instead of observation • Observation implies passivity • Measurement is an active process • Conceptualization – process of arriving at an agreement about meaning • Can occur between individuals, groups, or societies

3. Concepts As Constructs • 3 classes of things measured by scientists • 1] Direct observables – things easily and readily seen • 2] Indirect observables – learn vicariously • Class notes, meeting minutes, books • 3] Constructs – theoretical creations that cannot be observed directly or indirectly • IQ, theoretical propositions

4. Indicators & Dimensions • Indicator – a sign of the presence of the concept under study • Indicator of gang involvement might be attire, colours, hand signals, speech • Dimension – a specifiable aspect of a concept • We might speak of a family dimension to the gang or a violent dimension

5. Definitions • Real – provides an expression of the essential nature of an entity • Dictionaries do this • Nominal – one that is assigned to a term without any real claim that it defines a real entity • Although arbitrary there is some consensus about their representation of a real entity • Plucking bird feathers = compassion

6. More Definitions • Operational – specifies precisely how a researcher will measure a concept • Gang violence = robberies, rapes, murders, shootings • Specification – we specify concepts as we define them…more thorough definition • This is tautological (circular logic) • We specify concepts through specification

7. Conceptual Order • As a researcher develops their project they come to understand their concepts more intimately • Gang violence • Beat-in for males – beaten severely by existing gang members • Sexed-in for females – roll die & have sex with as many gang members as #’s on die • These are inherently violent activities • Researcher comes to understand other dimensions of violence

8. Anomie • Normlessness (Emile Durkheim) • Suicide is most normless action of a human • Suicide is the most violent act possible • Aggression & hate turned inward • Outburst against society • Concepts involved in this theory are used today to assist researchers in theory utilization and conceptualization for projects containing some violent factors

9. Levels of Measurement • Nominal – exhaustive & mutually exclusive • Only a certain number of categories • Observation can fit into one and only one category • Sex – Male or Female • Ordinal – rank is given • No meaning to ordering • Things that can be categorized along hi-medium-low

10. Levels of Measurement Continued • Interval – ranks now have meaning • No true zero point • Temperature °F • IQ • Ratio – true zero point • Kelvin temperature scale • Highest level of measurement • Most desired by researchers

11. Measurement Quality • Reliability – whether a measurement technique applied to a different object provides the same results • A scale that reads different weights at different times is unreliable • A chef that prepares gourmet food one day and fried burgers the next is unreliable • Replication of research helps increase reliability for measurement techniques

12. Measurement Quality Continued • Test-Retest Method • Researchers will often have subjects complete a pretest or a baseline measure before actual data is obtained • Once data is obtained researchers will go back and see if pretest responses were the same or similar to the post test • If responses vary greatly then the researcher needs to check the reliability of the measurement instrument

13. MQ • Split Half Method • A researcher will sometimes devise different sets of responses to survey or questionnaire items and then give those items to different groups of respondents • Half of the subjects get one set of responses • The other half gets the other set of responses • Afterward the two sets of responses are compared • The two sets of responses should yield very similar results

14. Validity • The extent to which an empirical measure adequately reflects the real meaning of the concept under consideration • You use a scale to measure your weight – not a ruler • A watch is used to tell time – not a fry pan • Measurement devices work the same way – a thermometer, a Likert scale

15. Validity Continued • Face Validity – the quality of a measure that makes it seem reasonable • If you were to study gang violence you would want to measure things such as shootings or robberies • Collecting information on shoe size or style of socks worn would be meaningless to overall concept

16. Validity Continued • Criterion Related Validity • How much a measure related to some external criterion • Tries to predict future happenings • SAT, ACT, LSAT • These exams try to predict future scholastic success

17. Validity • Construct Validity • How much or to what degree a measure relates to other variables within a system of relationships • Gang violence – you might count the number of shootings • BUT, if your gang were not ‘into’ shootings then your study would suffer from a lack of construct validity

18. Validity • Content Validity • How much a measure covers the range of meanings included in the concept • You want your measure of your construct to cover a broad range of possible behaviors • Gang violence – you wouldn't want to limit your study to shootings • Broaden a bit and you would get a better portrayal of gang violence