| 1.150 | measurement procedure with standard addition | ||
| standard addition | |||
| Measurement procedure in which indications are obtained for an analytical sample as well as for analytical samples with serial addition(s) of aliquots of a measurement standard. | |||
| Note 1: | A measurement procedure with standard addition provides an unbiased measurement result if there is a multiplicative matrix effect. | ||
| Note 2: | If the relation between the indications (y) and the quantities added (x) is obtained by linear regression of y on x, then the quantity in the analytical sample is x0 = b0/b1 where y = b0 + b1x, i.e. the intercept divided by the slope of a calibration curve. The standard uncertainty of the estimate x0, is | ||
 | |||
where sy/x is the standard error of the regression, n the number of additions, and  and  the means of the xi and yi respectively. (See ref. 62 p. 8 and p. 157). | |||
| See also: ref. 9. Source: ref. 2 entry 3.50 with added Note 2. | |||
| 1.150 | measurement procedure with standard addition | ||
| standard addition | |||
| Measurement procedure in which indications are obtained for an analytical sample as well as for analytical samples with serial addition(s) of aliquots of a measurement standard. | |||
| Note 1: | A measurement procedure with standard addition provides an unbiased measurement result if there is a multiplicative matrix effect. | ||
| Note 2: | If the relation between the indications (y) and the quantities added (x) is obtained by linear regression of y on x, then the quantity in the analytical sample is x0 = b0/b1 where y = b0 + b1x, i.e. the intercept divided by the slope of a calibration curve. The standard uncertainty of the estimate x0, is | ||
| | |||
| where sy/x is the standard error of the regression, n the number of additions, and and the means of the xi and yi respectively. (See ref. 62 p. 8 and p. 157). | |||
| See also: ref. 9. Source: ref. 2 entry 3.50 with added Note 2. | |||