<P> In psychometrics and psychophysics , the term accuracy is interchangeably used with validity and constant error . Precision is a synonym for reliability and variable error . The validity of a measurement instrument or psychological test is established through experiment or correlation with behavior . Reliability is established with a variety of statistical techniques , classically through an internal consistency test like Cronbach 's alpha to ensure sets of related questions have related responses , and then comparison of those related question between reference and target population . </P>
<P> In psychometrics and psychophysics , the term accuracy is interchangeably used with validity and constant error . Precision is a synonym for reliability and variable error . The validity of a measurement instrument or psychological test is established through experiment or correlation with behavior . Reliability is established with a variety of statistical techniques , classically through an internal consistency test like Cronbach 's alpha to ensure sets of related questions have related responses , and then comparison of those related question between reference and target population . </P>
the level of mathematical precision of a variable is called
the level of mathematical precision of a variable is called
variable error
variable error