Problems with Interval Estimation When Data are Adjusted via Calibration


Mulrow, Jeri M.; Vecchia, Dominic F.; Buonaccorsi, John P.; Iyer, Hari K.   (1988, ASQC)   National Bureau of Standards; University of Massachusetts; Colorado State University

Journal of Quality Technology    Vol. 20    No. 4
QICID: 5593    October 1988    pp. 233-247
List $10.00
Member $5.00

You will need to be signed in.
New to ASQ? Register here.

Article Abstract

The analysis of adjusted data arising from a linear calibration curve is considered. Although it is obvious that adjusted values contain errors due to estimation of the calibration curve, some investigators may be tempted to analyze such data as if they are true values of the property of interest. We illustrate some of the problems that arise if one applies "naive" analyses to calibrated data. In particular, it is shown that standard one-sample confidence intervals have actual confidence levels that are always less than the nominal value. We also propose and evaluate two other methods for constructing confidence intervals. Tolerance intervals derived from adjusted data also may yield deceiving results, having actual probability levels that are usually greater than the desired level but smaller in some cases


Calibration,Confidence intervals,Error,Tolerances

Browse QIC Articles Chronologically:     Previous Article     Next Article

New Search

Featured advertisers

ASQ is a global community of people passionate about quality, who use the tools, their ideas and expertise to make our world work better. ASQ: The Global Voice of Quality.