Linearity

Linearity is the property of a mathematical relationship. that can be graphically represented as a straight line. Linearity is closely related to proportionality. The Linearity of an analytical procedure is its ability to obtain the test results that are directly proportional to the concentration of analyte in the sample. Linearity is usually demonstrated by visual inspection of a plot of signals as a function of analyte concentration or content. If there is a linear test result should be evaluated by appropriate statistical methods. The correlation coefficient, y-intercept, slope of regression line and residual sum of square should be calculate. A minimum of five concentrations is recommended. Other approaches should be justified.