Dependent and independent variables

<p>A variable is considered dependent if it depends on an independent variable. Dependent variables are studied under the supposition or demand that they depend, by some law or rule (e.g., by a <a href="/facts/Mathematical_function/CdReEKCh">mathematical function</a>), on the values of other variables. Independent variables, in turn, are not seen as depending on any other variable in the scope of the experiment in question. In this sense, some common independent variables are <a href="/facts/Time/HceJKUGB">time</a>, <a href="/facts/Space/tq6LUM3C">space</a>, <a href="/facts/Density/92p6hh9I">density</a>, <a href="/facts/Mass/HHdc8XmF">mass</a>, <a href="/facts/Volumetric_flow_rate/X5KI7zzH">fluid flow rate</a>, and previous values of some observed value of interest (e.g. human population size) to predict future values (the dependent variable).
</p><p>Of the two, it is always the dependent variable whose variation is being studied, by altering inputs, also known as regressors in a <a href="/facts/Statistics/DNPsKGYU">statistical</a> context. In an experiment, any variable that can be attributed a value without attributing a value to any other variable is called an independent variable.  <a href="/facts/Conceptual_model/hgysE2kP">Models</a> and <a href="/facts/Experiment/esltM54f">experiments</a> test the effects that the independent variables have on the dependent variables. Sometimes, even if their influence is not of direct interest, independent variables may be included for other things, such as to account for their potential <a href="/facts/Confounding/G4TVx1dt">confounding</a> effect.
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Dependent and independent variables open-in-new

Dependent and independent variables