1. The Nature of Variables

2. Learning Objective To differentiate kinds of variables and their uses
Present the learning objective.

3. Key Understanding Key Question
Understanding of the different kinds of variables and their uses
Key Question
What are the different kinds of variables and their uses?
Tell the students that at the end of the lesson, they need to be able to understand the different kinds of variables and their uses. In addition, at the end of the lesson they should be able to answer the key question. Go back to the key understanding and key question before the lesson ends.

4. Variables
Are “changing qualities or characteristics” of persons or things like age, gender, intelligence, ideas, achievements, confidence, and so on that are involved in your research study.
Made up of the root or base word “vary” which means to undergo changes or to differ from, variables have different or varying values in relation to time and situation.
Tell your students: For instance, as years go by, your age or intelligence increases. But placed in a situation where you are afflicted with a disease or have no means of reading or no access to any sources of knowledge, your intelligence tend to decrease (Suter 2013, p. 137).
In research, especially in a quantitative research, one important thing you have to focus on at the start of your study is to determine the variables involved in your study. Unless you spend some time pondering on variables in your research, your work has no chance of attaining its goal. Your research problem or research topic to which you devote much of your initial research time finalizing stands great, if it has wordings on the basic variables involved in your study.

5. Types of Variables
Independent variables are those that cause changes in the subject
Dependent variables are those that bear or manifest the effects caused by the independent variables.

6. Variable Relationships
In a scientific way of studying cause-effect relationships, these two variables, independent and dependent are part and parcel of the research because the first one is the cause; the second, the effect that you can subject to any form of measurement.

7. Variable Relationships
However, as you carry out the research, it is possible that one, two, or more variables or extra variables crop up to create an impact on the relationship between the independent and dependent variables. Being extra variables, they form this other type of variables called extraneous variables.

8. Variable Relationships
For example, in the case of SFG vs. IC, (the first as the independent variable; the second as the dependent variable) extraneous variables like age, gender, or personality traits may suddenly surface to create effects on the relationships of the two basic variables. Such extraneous variables are called participant variables if they refer to the moods, emotions, or intelligence of the subject; situational variables, if they pertain to nature of the place: smelly, chilly, cold, hot, spacious, and the like.
Refer to page 30 of the book.

9. Other Types of Variables
Extraneous variables are to be controlled by you, the experimenter. But if they do not give in to your control, they become confounding variables that can strongly influence your study.
Involved not within the research situation but outside the research process, the extraneous variables exist as “nuisance variables,” whose potency need to go down to prevent it from affecting the results negatively. (Suter 2013, p. 137; Thomas 2013; Schreiber 2012).
Tell your students that dealing with these types of variables gives them difficulty in determining the real cause of changes in the dependent variables; that is, whether it is due only to the independent variable or to the combination between the confounding and the independent variables. The involvement of confounding variables in the research results in the production of “mixed up, confusing, or bewildering results.”

10. Other Types of Variables
(Russell 2013; Babbie 2013)
Constant – do not undergo any changes during an experiment
2. Attribute – characteristics of people: intelligence, creativity, anxiety, learning styles, etc.
3. Covariate – included in the research study to create interactions with the independent and dependent variables

11. Other Types of Variables
(Russell 2013; Babbie 2013)
4. Continuous – quantitative in nature and is used in interval or ratio scale of measurement 5. Dichotomous – has only two possible results: one or zero 6. Latent – cannot be directly observed like personality traits

12. Other Types of Variables
(Russell 2013; Babbie 2013)
7. Manifest – can be directly observed to give proofs to latent variables 8. Exogenous – found outside an identified model 9. Endogenous – found inside; as a part of identified model