Nalimov test

Outlying data sets (Dixon, Nalimov tests)" NO NO NO NO... 

The statistical treatment involves tests, e.g. to assess the conformity of the distributions of individual results and of laboratory means to normal distributions (Kolmogorov-Smimov-Lilliefors tests), to detect outlying values in the population of individual results and in the population of laboratory means (Nalimov test), to assess the overall consistency of the variance values obtained in the participating laboratories (Bartlett test), and to detect outlying values in the laboratory variances (s ) (Cochran test). One-way analysis of variance (F-test) may be used to compare and estimate... 

Once a technical evaluation has been carried out, a statistical analysis is needed to confirm the absence of outlying means, examine the precision of the data, and evaluate the certified (or assigned) values and their uncertainties. A wide range of statistical tests exist in this respect they are based on the calculation of the mean values obtained by different laboratories and/or methods and a study of their distribution, and an analysis of the variances obtained. Examples are the Dixon (Nalimov) test for the evaluation of the... 

Nalimov Test Given a series of measuring values with the characteristic standard data n, x, and s, the test quantity r is calculated by putting the value x, a suspected outlier, into Eq. (9.42) ... 

The test according to Grubbs differs from that of Nalimov by the test quantity rm, which is calculated by Eq. (211) as follows ... 

The evaluation of the distribution of means is performed through a Dixon test (Nalimov). If outlying mean values remain after the technical discussion, it demonstrates that biased results remain and that this technical examination was unreliable. The parameter cannot be certified as a doubt remains on the trueness of the data. 

Following the technical evaluation, the sets of accepted results were submitted to statistical tests (Kolmogorov-Smimov-Lilliefors, Nalimov, Bartlett and Cochran tests, and one-way analysis of variance) which are described in detail in the certification report [86]. The certified values (unweighted mean of p accepted sets of results) and their uncertainties (half-width of the 95% confidence intervals) are given in the Table 4.3 as mass fractions (based on dry mass). Total and methylmercury are certified as mass fractions (mg kg ) of Hg and MeHg" respectively. 

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