RESEARCH ON ELT I

Lecture II

Rida Wahyuningrum

English Department

Wijaya Kusuma University, Surabaya

By the end of this course, you will be

able to :

mention the definition

and types of variable

What is

Variable?

VARIABLE

A measurable characteristic

that varies and may change

from group to group, person to

person, or even within one

person over time.

An attribute of a person or of an

object which ‘varies’ from person

to person or from object to object”

( Hatch and Farhady, 1982:2).

Conditions by which the

researcher manipulates,

controls, or observes in a

study.

(YW Best)

VARIABLE

TYPES OF VARIABLES

NOMINAL/CATEGORICAL

VARIABLE

A categorical variable (sometimes called a nominal variable) is one that has two or more categories, but there is no intrinsic ordering to the categories.

Example : gender, marital status,

kinds of job

ORDINAL VARIABLE

An ordinal variable is similar to a categorical variable but there is a clear ordering of the variables. For example, suppose you have a variable.

Example : economic status, with three categories (low, medium and high).

INTERVAL VARIABLE

An interval variable is similar to an ordinal variable, except that the intervals between the values of the interval variable are equally spaced.

Example : annual income with three people who make $10,000, $15,000 and $20,000 . The interval is the same.

RATIO VARIABLE

This variable has all the properties of an interval variable, and also has a clear definition of 0.0. When the variable equals 0.0, there is none of that variable.

Example : height, weight, enzyme activity. Temperature, expressed in F or C, is not a ratio variable. A temperature of 0.0 on either of those scales does not mean 'no heat'. However, temperature in Kelvin is a ratio variable, as 0.0 Kelvin really does mean 'no heat'.

DEPENDENT VARIABLE

This variable shows the effect of manipulating or introducing the independent variables.

For example, if the independent variable is the use or non-use of a new language teaching procedure, then the dependent variable might be students' scores on a test of the content taught using that procedure.

INDEPENDENT VARIABLE

These variables are those that the researcher has control over. This "control" may involve manipulating existing variables (e.g., modifying existing methods of instruction) or introducing new variables (e.g., adopting a totally new method for some sections of a class) in the research setting.

INTERVENING VARIABLE

This refers to abstract processes that are not directly observable but that link the independent and dependent variables. In language learning and teaching, they are usually inside the subjects' heads, including various language learning processes which the researcher cannot observe.

For example, if the use of a particular teaching technique is the independent variable and mastery of the objectives is the dependent variable, then the language learning processes used by the subjects are the intervening variables.

MODERATOR VARIABLE

This variable affects the relationship between

the independent and dependent variables by

modifying the effect of the intervening

variable(s). These variables are measured

and taken into consideration. Typical

moderator variables in TESL and language

acquisition research (when they are not the

major focus of the study) include the sex,

age, culture, or language proficiency of the

subjects.

CONTROLLED VARIABLE

Language learning and teaching are very

complex processes. It is not possible to

consider every variable in a single study.

Therefore, the variables that are not

measured in a particular study must be held

constant, neutralized/balanced, or

eliminated, so they will not have a biasing

effect on the other variables.

CONTROLLED VARIABLE

For example:

Comparing cleaning products, the brand of

cleaning product would be the only independent

variable measured. The level of dirt and soiling, the

type of dirt or stain, the temperature of the water

and the time of the cleaning cycle are just some of

the variables that must be the same between

experiments. Failure to standardize even one of

these controlled variable could cause a

confounding variable and invalidate the results.

EXTRANEOUS VARIABLE

Extraneous variables are undesirable

variables that influence the relationship

between the variables that an experimenter

is examining. These are variables that

influence the outcome of an experiment,

though they are not the variables that are

actually of interest. These variables are

undesirable because they add error to an

experiment.

EXTRANEOUS VARIABLE

For example:

An educational psychologist has developed a new

learning strategy and is interested in examining the

effectiveness of this strategy. The experimenter

randomly assigns students to two groups. All of the

students study text materials on a biology topic for

thirty minutes. One group uses the new strategy and

the other uses a strategy of their choice. Then all

students complete a test over the materials. One

obvious confounding variable in this case would be

pre-knowledge of the biology topic that was studied.

This variable will most likely influence student scores,

regardless of which strategy they use.