Variable

Sarfraz Ahmad
Lecturer
KUST Kohat

1. Variable

2. Variable A  variable is any characteristics, number, or quantity that can be measured or counted .  A variable may also be called a  data item . Age , sex, business income and expenses, country of birth, capital expenditure, class grades, eye colour and vehicle type are examples of variables. It is called a variable because the value may vary between data units in a  population , and may change in value over time. 

3. Variable For example ; 'income ' is a variable that can vary between data units in a population (i.e. the people or businesses being studied may not have the same incomes) and can also vary over time for each data unit (i.e. income can go up or down). 

4. Variable Definition : A variable is a label or name that represents a concept or characteristic that varies (e.g., gender, weight, achievement, attitudes toward inclusion, etc.)

5. Concept of Variable Conceptual Definition of the Variable Conceptual (i.e., constitutive) definition uses words or concepts to define a variable Achievement : what one has learned from formal instruction Aptitude : one's capability for performing a particular task or skill

6. Concept of Variable Operational Definition of the Variable Operational definition is an indication of the meaning of a variable through the specification of the manner by which it is measured, categorized, or controlled Weschler IQ score Income levels below and above $45,000 per year Use of holistic or phonetic language instruction

7. Types of Variable

8. Types of Variable

9. Types of Variable 1-Independent and Dependent (i.e ., cause and effect) a. Independent variables act as the " cause" in that they precede, influence, and predict the dependent variable b. Dependent variables act as the effect in that they change as a result of being influenced by an independent variable

10. Types of Variable Examples The effect of two instructional approaches (independent variable) on student achievement (dependent variable) The use of SAT scores (independent variable) to predict freshman grade point averages (dependent variable)

11. Types of Variable Note : Some situations do not lend themselves to the use of the terms independent or dependent because it is difficult to discuss them in causal terms The relationship between attitude and achievement , that is, do positive attitudes cause high achievement or does high achievement cause positive attitudes? The relationship between creativity and critical thinking , that is, do high levels of creativity cause higher levels of critical thinking or do higher levels of critical thinking cause greater creativity?

12. Types of Variable 2-Extraneous and Confounding Variables a:- Extraneous variables are those that affect the dependent variable but are not controlled adequately by the researcher Not controlling for the socio-economic status of students involved in a study of the effects of instructional technologies Not controlling for the key-boarding skills of students in a study of computer-assisted instruction

13. Types of Variable 2-Extraneous and Confounding Variables b:- Confounding Variables are those that vary systematically with the independent variable and exert influence of the dependent variable Not using counselors with similar levels of experience in a study comparing the effectiveness of two counseling approaches Not using the same test to measure the effectiveness of two instructional approaches

14. Types of Variable 3-Continuous and categorical a-Continuous variables are measured on a scale that theoretically can take on an infinite number of values Test scores range from a low of 0 to a high of 100 Attitude scales that range from very negative at 0 to very positive at 5 Students ' ages

15. Types of Variable 3-Continuous and categorical b-Categorical variables Categorical variables are measured and assigned to groups on the basis of specific characteristics Examples Gender : male and female Grade level: K-12 Socio-economic status: low, middle, and high The term level is used to discuss the groups or categories Gender has two levels - male and female Socio-economic status has three levels - low, middle , and high

16. Note : Continuous variables can be converted to categorical variables , 2. but categorical variables cannot be converted to continuous variables IQ is a continuous variable, but the researcher can choose to group students into three levels based on IQ scores - low is below a score of 84, middle is between 85 and 115, and high is above 116 Test scores are continuous, but teachers typically assign letter grades on a ten point scale (i.e., at or below 59 is an F, 60 to 69 is a D, 70 to 79 is a C, 80-89 is a B, and 90 to 100 is an A

17. Thank You