Analysis of key comparison data: assessment of current methods for determining a reference value
نویسنده
چکیده
The degree of equivalence of national measurement standards is established by means of key comparisons. The analysis of data from a key comparison requires the determination of a reference value, which is then used to express the degree of equivalence of the national measurement standards. Several methods for determining a reference value are available and these methods can lead to different results. In this study current methods for determining a reference value are compared. In order to quantitatively assess the quality of performance, the methods are applied to a large set of simulated key comparison data. The simulations refer to several realistic scenarios, including correlated measurements. Large differences in the results can occur and none of the methods performs best in every situation. We give some guidance for selecting an appropriate method when assumptions about the reliability of quoted uncertainties can be made.
منابع مشابه
Comparision of Methods for Determining Bearing Capacity of Piles Using Standard Penetration Test (SPT) Data
In recent years, determining bearing capacity of piles from in-situ testing data as a complement to static and dynamic analysis has been used by geotechnical engineers. In this paper, different approaches for estimating bearing capacity of piles from SPT data are studied and compared. A new method based on N value from SPT is presented. Data averaging, failure zone and plunging failure of pil...
متن کاملComparision of Methods for Determining Bearing Capacity of Piles Using Standard Penetration Test (SPT) Data
In recent years, determining bearing capacity of piles from in-situ testing data as a complement to static and dynamic analysis has been used by geotechnical engineers. In this paper, different approaches for estimating bearing capacity of piles from SPT data are studied and compared. A new method based on N value from SPT is presented. Data averaging, 
failure zone and plunging failure of p...
متن کاملThe Assessment of Operational Efficiency of Commercial Banks in India Using Cost to Income Ratio Approach
During the last two decades, financial institutions worldwide have witnessed a lot of stress in managing their margins in wake of the new risks, challenges and increase in the competition posed to them by the factors of liberalization and deregulation. The key to create value and achieve competitive edge lies in the better operational efficiency and productivity of these institutions under such...
متن کاملDetermining the Reference Value in Forest Policy of Kalgachi Local System, Zagros Forest, Chaharmahal and Bakhtiari Province
Sustainable forest management standards and measurement instruments subject and use them as the main tool is very important for monitoring and control in forest management. Sustainable progress monitoring and measuring possible by tools and standards. Tools and standards to help sustainable forest management can be more accurate and better information provided to forest managers and decision-ma...
متن کاملA Discussion of Approaches for Determining a Reference Value in the Analysis of Key-comparison Data
When analysing a sample statistically, the quality of the resulting parameters (measures of location, dispersion, etc.) depends on the reliability or credibility of the data and on the analysis undertaken. The data provided by interlaboratory comparisons, and especially key comparisons, is of sufficient importance that approaches are required which are as defensible and robust as possible. Cent...
متن کامل