Relative Change and Difference

Relative Change And Difference

In any quantitative science, the terms relative change and relative difference are used to compare two quantities while taking into account the "sizes" of the things being compared. The comparison is expressed as a ratio and is a unitless number. By multiplying these ratios by 100 they can be expressed as percentages so the terms percentage change, percent(age) difference, or relative percentage difference are also commonly used. The distinction between "change" and "difference" depends on whether or not one of the quantities being compared is considered a standard or reference or starting value. When this occurs, the term relative change (with respect to the reference value) is used and otherwise the term relative difference is preferred. Relative difference is often used as a quantitative indicator of quality assurance and quality control for repeated measurements where the outcomes are expected to be the same. A special case of percent change (relative change expressed as a percentage) called percent error occurs in measuring situations where the reference value is the accepted or actual value (perhaps theoretically determined) and the value being compared to it is experimentally determined (by measurement).

Read more about Relative Change And Difference:  Definitions, Formulas, Percent Error, Percentage Change, Other Change Units, See Also

Famous quotes containing the words relative, change and/or difference:

    She went in there to muse on being rid
    Of relative beneath the coffin lid.
    No one was by. She stuck her tongue out; slid.
    Gwendolyn Brooks (b. 1917)

    I don’t think that a leader can control to any great extent his destiny. Very seldom can he step in and change the situation if the forces of history are running in another direction.
    Richard M. Nixon (1913–1995)

    I waited and worked, and watched the inferior exalted for nearly thirty years; and when recognition came at last, it was too late to alter events, or to make a difference in living.
    Ellen Glasgow (1873–1945)