Question

Compare independent variables, dependent variables, and extraneous variables. Describe two ways that researchers attempt to control extraneous variables. Support your answer with peer-reviewed articles.

Answer 1

Answer :

Independent variables :

It is a variable which can be changed or controlled in a scientific research or an experiment to test the effects on the dependent variable.

Which can be controlled or manipulated.

Dependent variable :

It can be tested and measured in a scientific research or experiment.

These are affected by our changes to the independent variables.

Extraneous variables :

These are variables other than the dependent and independent variables.

Extraneous variables are confound the relationship between the dependent variable and independent variables.

For example :

Smoking causes lung cancer.

In these smoking is the " independent variable ".

and lung cancer is the " dependent variable ".

In these independent variable we can manipulate, by health education to avoid smoking, so it may affect on lung cancer by reducing symptoms.

So by manipulating independent variable, it can affect on dependent variable.

But extraneous variable is " air pollution ".

It is also cause for lung cancer but it is extraneously.

It interferes the studying between the independent variable and dependent variable.

Two ways researchers attempts to control the extraneous variables :

1. Randomization : by random assignment of tests we can control.

2. Statistical control : by measuring extraneous variables and adjusting their effects through statistical analysis

3. Design control : the research should be designed according to control extraneous variables.