What is an extraneous variable?
In an experiment, an extraneous variable is any variable that you’re not investigating that can potentially affect the outcomes of your research study. If left uncontrolled, extraneous variables can lead to inaccurate conclusions about the relationship between independent and dependent variables.
What is independent dependent and extraneous variables?
The dependent variable is the variable a researcher is interested in. An independent variable is a variable believed to affect the dependent variable. Extraneous variables are defined as any variable other than the independent and dependent variable.
What is another term that refers to a confounding extraneous variable?
When we conduct experiments there are other variables that can affect our results, if we do not control them. Extraneous variables are all variables, which are not the independent variable, but could affect the results of the experiment. These other variables are called extraneous or confounding variables.
How do you identify extraneous variables?
Extraneous variables are any variables that you are not intentionally studying in your experiment or test. When you run an experiment, you’re looking to see if one variable (the independent variable) has an effect on another variable (the dependent variable).
How do you stop a confounding variable?
There are various ways to modify a study design to actively exclude or control confounding variables (3) including Randomization, Restriction and Matching. In randomization the random assignment of study subjects to exposure categories to breaking any links between exposure and confounders.
How do you classify a variable?
Classifying variables can be somewhat contentious. Standard statistical textbooks will state that variables can be broadly classified as categorical or continuous. Categorical variables can be further categorised into nominal (e.g. ethnic group), ordinal (e.g. tumour staging) and dichotomous (e.g. sex).
What are variables and how do we classify them?
Parts of the experiment: Independent vs dependent variables
| Type of variable | Definition |
|---|---|
| Independent variables (aka treatment variables) | Variables you manipulate in order to affect the outcome of an experiment. |
| Dependent variables (aka response variables) | Variables that represent the outcome of the experiment. |
What type of variable is attitude?
In the above examples, sex is an example of a nominal scale of measurement, or a classification or categorization; attitude is ordinal, or an ordering or ranking of responses; and age has an interval and ratio scale of measurement, with meaningful measures of distances and ratios between values.
What type of variable is characterized by evenly?
If the categories are equally spaced, then the variable is an interval variable. Just like an ordinal variable, an interval variable also has two or more categories which can also be ordered from high to low, BUT the intervals between the values of the interval variable are equally spaced.