Correction to: Improving performance evaluation via the provision of proficiency testing programmes in Asia–Pacific with metrologically traceable reference values for inorganic elements (original) (raw)
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The Annals of Applied Statistics, 2019
The abcissa on certain figures in "Statistical Modeling and Analysis of Trace Element Concentrations in Forensic Glass Evidence" [Pan and Kafadar (2018)] and the corresponding supplement have been corrected. Estimated match rates are around 20-30% lower than originally stated (when the true relative difference in concentrations is less than 15% in all elements); however, the main results and conclusions of the paper remain unchanged. Two samples that come from batches whose mean log concentrations differ by δ = 0.1 (roughly 10%) in all 17 elements would not be "considered distinguishable" [ASTM International (2016), Section 11.1.7] 62.22-65.41% of the time using the covariance matrix estimate from the German data, and 77.18-78.14% of the time using the estimate from the Canadian data set. Affected figures and tables below are labeled corresponding to Pan and Kafadar (2018). Section 2 contains corrected supplemental figures and tables.
Chemical Geology, 1992
The quality of analytical data obtained from cost-effective commercial multi-element "packages" is examined with respect to its use in tectonic interpretation studies. Good accuracy and precision in the determination of high field strength elements, Zr, Y, Ti, Nb, Hf, Ta and the rare-earth elements (REE) is essential in extracting the correct and maximum information for discrimination diagrams. Misinterpretation can result from the use of noisy and biased analylical data; this is shown by the poor quality of results for Y and Nb where the concentrations measured are close to the method's detection limits. A "round-robin" study to determine Zr, Nb, Hf and Ta demonstrates the significant variability to be expected amongst laboratories, even for elements with relatively high abundance levels, such as Zr. The round-robin results are compared with a sensitive analytical method based upon inductively coupled plasma-mass spectrometry (ICP-MS) and LiBO2 fusion. The inefficiency of the common mixed-acid attack (HF-HCIO4-HNO3-HC1) to dissolve the heavy REE in some samples is proven by comparison with results employing a fusion decomposition and with instrumental neutron activation analysis. Such a partial attack prior to analysis can lead to an erroneous chondrite-normalised pattern, incorrectly suggesting light-REE enrichment and masking positive or negative Eu anomalies.
Correction to: Quantitative SPECT/CT imaging of lead-212: a phantom study
EJNMMI Physics, 2022
Following publication of the original article [1], an error in Fig. 1 was reported by the authors. In the top blue box, the intensity of the 87.1 keV X-ray was quoted as 1.2%, but it should be 2.0%. The updated figure is provided in this correction article. The authors would also like to specify that a scatter filter of 12 mm was used for all the SPECT images analysed. The 'no filter' results refer to images where no post-filter was applied. The original article [1] has been updated.