Constructs and Variables

1. Constructs and Variables S. Kathleen Kitao Kenji Kitao Keywordsconstruct, variable, operationalization, operational definition

2. will discuss • Relationship between: • actual characteristic the researcher is looking at • how that characteristic is measured

3. Differences between Constructs and Variables • A variable is essentially what we can observe or measure of a characteristic or ability. • A construct is the underlying characteristic or ability itself.

4. Measuring constructs • Some constructs, such as height or weight can be measured directly. • Other constructs, such as closeness of a friendship, cannot be measure directly. • Researchers use questionnaires, interviews, or observation instead.

5. Example of questionnaire measuring closeness of friendship • Ask participants to agree or disagree with statements like these: • 1. I spend as much time with my friend as possible. • 2. If my friend needed $100, and I had the money, I would give it to her. • 3. I can trust my friend with a secret. • These measure such aspects of closeness of a friendship as time spent together, willingness to help, and trust.

6. It is important to keep in mind, however, that though the results of such a questionnaire are intended to reflectthe closeness of a friendship, the results are not themselves the closeness of a friendship. • In doing or evaluating research, you must think about how well the measures used for the variables actually reflect the underlying construct they are intended to reflect.

7. Operationalization • Operationalization is the link between the construct and the way it is measured; the operational definition of a variable is the way that it is measured or quantified. • For example, English proficiency might be operationalized as • a TOEFL score • a rating of a person's ability to carry on a conversation in English under certain conditions • the results of a reading test.

8. Requirements of an Operational Definition • 1. It must be conceptually linked to the construct that it is intended to represent, that is, it must measure the characteristics that the concept actually has. • In the questions about the closeness of a friendship above, the three questions could be intended to measure time spent together, willingness to help, and trust.

9. It is assumed that these are some of the characteristics that a close friendship would have. • In measuring closeness of friendships, you should think about the characteristics of friendship and ask questions about those characteristics. • In addition, the questions should not measure any characteristics that should not be included in the construct. • For example, the question, "My friend is rich" would not be an appropriate as part of the above questionnaire, if the amount of money the friend has is not a characteristic of closeness of friendship.

10. If you are measuring English proficiency, you need to think about what kind of proficiency you want to measure. • If your hypothesis is that the higher speaking proficiency is, the better chance a nonnative speaker has of forming friendships with Americans.

11. For the purpose of your research, you need to measure speaking. What is the best way of measuring speaking? • You could ask subjects of the research to prepare a speech. But that type of speaking is not related to forming friendships. • In this case, a better way to measure speaking ability would be to have the subject carry on a conversation and rate speaking ability based on that conversation.

12. 2. Secondly, an operational definition must be unique to that concept, that is, it must measure that concept and no other. • For example, a test of listening proficiency that requires some reading may also be measuring reading proficiency. That is, the score for listening proficiency may be influenced by ability to read. • In that case, the operational definition includes a concept that the researcher did not intend to measure.

13. The Importance of Operational Definitions • Operational definitions are important for three reasons. • 1. A clear operational definition allows researchers to be consistent throughout the research. • 2. it allows readers of the research to clearly understand the findings. • 3. It allows other researchers to do the same research to see if they get the same results.

14. Clear definitions of constructs are important. • In considering the relationship between variables and constructs when you read a research paper or do research yourself, it is necessary to consider the definitions that the researcher uses for the construct, if they are specified.

15. Whether a variable truly reflects a construct is, in part, dependent on how that construct is defined. • For example, if the definition of English proficiency is related to fluency in speaking English, then a TOEFL score is not a good operationalization, because the TOEFL emphasizes a knowledge of grammar, reading comprehension, and other factors that are not be related to the ability to fluency in speaking.

16. Conclusion • Social scientists study many phenomena that cannot be measured directly. • The actual phenomenon is called a construct; the results of the measurement of that construct is called a variable. • One of the most important issues in social science is the relationship between constructs and variables, and whether a particular variable accurately represents a construct.