Everything about Dependent Variable totally explained
Dependent variables and independent variables refer to values that change in relationship to each other. The
dependent variables are those that are observed to change in response to the
independent variables. The
independent variables are those that are deliberately manipulated to invoke a change in the dependent variables. In short, "if
x is given, then
y occurs", where
x represents the independent variables and
y represents the dependent variables.
Depending on the context, independent variables are also known as
predictor variables,
regressors,
controlled variables,
manipulated variables, or
explanatory variables.
The dependent variable is also known as the
response variable, the
regressand, the
measured variable, the
responding variable, the
explained variable, or the
outcome variable.
Mathematics
In
mathematics, an
independent variable is any of the
arguments, for example "inputs", to a
function. These are contrasted with the
dependent variable, which is the value, for example the "output", of the function. Thus if we've a function
f(
x), then
x is an independent variable, and
f(
x) is a dependent variable. The dependent variable depends on the independent variables; hence the names.
When there's only one independent variable and its values and those of the dependent variable are
real numbers, then one conventionally draws the
graph of the function with values of the independent variable on the horizontal axis—the
x-axis—and the values of the dependent variable on the vertical axis—the
y-axis (see
Cartesian coordinates).
In
calculus, the identification of the independent and dependent variable is significant, since the rate of change, or
derivative, of the dependent variable is calculated
with respect to the independent variable.
Experiments
In the
design of experiments,
independent variables are those whose values are controlled or selected by the experimenter to determine its relationship to an
observed phenomenon (the dependent variable). In such an experiment, an attempt is made to find evidence that the values of the independent variable determine the values of the dependent variable (that which is being measured). The independent variable can be changed as required, and its values don't represent a problem requiring explanation in an analysis, but are taken simply as given. The dependent variable on the other hand, usually can't be directly controlled.
Controlled variables are also important to identify in experiments. They are the variables that are kept constant to prevent their influence on the effect of the independent variable on the dependent. Every experiment has a controlling variable, and it's necessary to not change it, or the results of the experiment won't be valid.
In summary:
- The independent variable answers the question "What do I change?".
- The dependent variable answers the question "What do I observe?".
- The controlled variable answers the question "What do I keep the same?".
Examples
If one were to measure the influence of different quantities of fertilizer on plant growth, the independent variable would be the amount of fertilizer used (the changing factor of the experiment). The dependent variables would be the growth in height and/or mass of the plant (the factors that are influenced in the experiment) and the controlled variables would be the type of plant, the type of fertilizer, the amount of sunlight the plant gets, the size of the pots, etc. (the factors that would otherwise influence the dependent variable if they were not controlled).
In a study of how different doses of a drug affect the severity of symptoms, a researcher could compare the frequency and intensity of symptoms (the dependent variables) when different doses (the independent variable) are administered, and attempt to draw a conclusion.
In measuring the acceleration of a vehicle, time is usually the independent variable and speed is the dependent variable. This is because when taking measurements, times are usually predetermined, and the resulting speed of the vehicle is recorded at those times. As far as the experiment is concerned, the speed is dependent on the time. Since the decision is made to measure the speed at certain times, time is the independent variable.
In measuring the amount of color removed from beetroot samples at different temperatures, the dependent variable would be the amount of pigment removed, because it's depending on the temperature (which is the independent variable).
In sociology, in measuring the effect of education on income or wealth, the dependent variable could be a level of income or wealth measured in monetary units (United States Dollars for example), and an independent variable could be the education level of the individual(s) who compose(s) the household (for example academic degrees).Further Information
Get more info on 'Dependent Variable'.
|
External Link Exchanges
Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:
<a href="http://dependent_and_independent_variables.totallyexplained.com">Dependent and independent variables Totally Explained</a>
Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned. |
