FP6 priority
1.1.5   Food Quality and Safety
Title of the proposal

Statistical Methods for Interlaboratory Comparisons

Institute
Slovak Academy of Sciences, Institute of Measurement Science
Dubravska cesta 9, 84219 Bratislava, Slovak Republic
www.um.savba.sk
Contact
Name:
Viktor WITKOVSKY, RNDr., PhD.
Phone:
+421 2 54788372
E-mail:
umerwitk@savba.sk


Research subject for a potential FP6 project

The problem of interlaboratory comparisons is of particular interest for applications that are looking for harmonization of industrial and scientific practice. Questions of fundamental importance in the analysis of the data coming from the interlaboratory comparisons are:
  • how to form the best consensus mean, and what uncertainty to attach to this estimate, and
  • how to detect and estimate the between laboratory variability.
    The primary objective of the suggested project is to develop the appropriate and state-of-the-art statistical methods for the analysis of the data from the interlaboratory comparisons. This project will produce novel statistical procedures for problems that do not satisfy the prerequisites of existing statistical methods. From methodological point of view, we will use our experience with combining statistical distributions under small sample assumptions and with making statistical inference in mixed linear models. The work conducted under this project will be presented mainly in statistical journals.


  • Recent international cooperation of the research team

    NIST - National Institute of Standards and Technology, Statistical Engineering Division, Gaithersburg, MD, USA (Prof. Andrew Rukhin).


    Proposerīs relevant publications related to the research subject

    1. Witkovsky V. and Wimmer G. (2001): On statistical models for consensus values. In: Frollo I., Tysler M., and Plackova A. (Eds.) MEASUREMENT 2001, Proceedings of the 3rd International Conference on Measurement, Smolenice, May 14-17, 2001, 32-35, See also:
    http://www.measurement.sk
    .
    2. Witkovsky V., (2001): On the exact computation of the density and of the quantiles of linear combinations of t and F random variables. Journal of Statistical Planning and Inference, Vol. 94, Issue 1, 1–13.
    3. Witkovsky V., (2002): Exact distribution of positive linear combinations of inverted chi-square random variables with odd degrees of freedom. Statistics and Probability Letters. Vol. 56/1, 45-50.
    4. G. Wimmer and V. Witkovsky: Between group variance component interval estimation for the unbalanced heteroscedastic one-way random effects model, Submitted to Journal of Statistical Computation and Simulation.