Homogeneity and Heterogeneity Study of an Ordinal Property Test Results: Analysis of Variations and Uncertainties

• Activity Number: 653
• Type: Contributed
• Date/Time: Thursday, August 2, 2012 : 10:30 AM to 12:20 PM
• Sponsor: Quality and Productivity Section
• Author(s): Emil Bashkansky*+ and Tamar Gadrich
• Companies: ORT Braude College and Ort Braude College
• Keywords: Analysis of variance ; Ordinal property ; Inter-laboratory comparison ; Proficiency testing ; Method validation ; Traceability

Abstract

Applications of a new statistical method Ordinal Analysis of Variance (ORDANOVA) for inter-laboratory comparisons of measurement or test results of semi-quantitative (ordinal) and qualitative (binary) properties are discussed. ORDANOVA can be helpful for validation of measurement or test methods, proficiency testing of laboratories, development of reference materials with certified semi-quantitative and qualitative properties, distinctive factors identification etc., that is, probably in every field where ANOVA is applied for quantitative properties. Unbiased statistics and criteria are proposed for performance assessment of laboratories active in semi-quantitative and qualitative testing and for other purposes of statistical analysis of such test results. Using Markov chains the problem of traceability and cumulative uncertainty of test results for hierarchically structured ladder of laboratories is also studied