In mathematics, an<unk> <unk> is any of the arguments, i.e. "inputs", to a function.  These are contrasted with the<unk> <unk>  which is the value, i.e. the "output", of the function. Thus if we have a function f(x), then x is an<unk> <unk>  and f(x) is a<unk> <unk>   The<unk> <unk> depends on the<unk><unk> ; hence the names.
When there is only one<unk> <unk> and its values and those of the<unk> <unk> are real numbers, then one conventionally draws the graph of the function with values of the<unk> <unk> on the horizontal axis—the x-axis—and the values of the<unk> <unk> on the vertical axis—the y-axis (see Cartesian coordinates).
In calculus, the identification of of the<unk>  and<unk> <unk> is significant, since the rate of change, or derivative, of the<unk> <unk> is calculated with respect to the<unk> <unk> 
Depending on the context,<unk><unk>  are also known as predictor<unk> , regressors, controlled<unk> , manipulated<unk> , or explanatory<unk> .
The<unk> <unk> is also known as the response<unk>  the regressand, the measured<unk>  the responding<unk>  the explained<unk>  or the outcome<unk>
Dependent and independent variables
Absolute deviation
Random variable
Biased sample
Ancillary statistic
Bias of an estimator
Attributable risk
Non-parametric statistics