Statistical assessment

McIntyre GA, Brooks C, Compston W, Turek A (1966) The statistical assessment of Rb-Sr Isochrons. J Geophys Res 71 5459-5468... 

Box 3. Statistical assessment of morbidity in technogenic and agrogenic biogeochemical provinces of North Eurasia (after Evstafyeva et al., 1999)... 

Luoma, S. N. and Bryan, G. W. (1981). A statistical assessment of the form of trace metals in oxidized estuarine sediments employing chemical extractants, Sci. Total Environ., 17, 165-196. 

An application of the confidence interval concept central to most statistical assessment is the t2-test for small normal samples. Let us consider a normally distributed variable X with mean p and variance a2. It will be demonstrated below that for m observations with sample mean x and variance s2, the variable U defined as... 

Discussing practical aspects of the inverse model such as stability, resolution, and statistical assessment would require considerably more development of the subject than presented here. For these important topics, the reader can consult the references quoted above and their enclosed bibliography. 

Tsong Y, Hammerstrom T, Sathe P, Shah VP. Statistical assessment of mean differences between two dissolution data sets. Drug Inf J 1996 30 1105-1112. 

Standard error of the mean (SEMI Is a statistical assessment of the increased confidence in a result ighen ft isthe meert of a iiQfinM numw or. replicates rather than a single measurement... 

A natural extension of analytical automation is some means of data processing all the results that are generated. This usually takes the form of a central computer which accepts information from different analysers for presentation in a useful manner. The identification of a sample and the tests performed are typed in using a keyboard and the computer collates all the data on each sample. As well as collecting information, computing and statistically assessing results, an important facility of the computer lies in its ability to store information for future recall via a visual display unit. 

National Statistical Assessment of Rural Water Conditions Executive... 

These same analysis techniques can be applied to chemical imaging data. Additionally, because of the huge number of spectra contained within a chemical imaging data set, and the power of statistical sampling, the PLS algorithm can also be applied in what is called classification mode as described in Section 8.4.5. When the model is applied to data from the sample, each spectrum is scored relative to its membership to a particular class (i.e. degree of purity relative to a chemical component). Higher scores indicate more similarity to the pure component spectra. While these scores are not indicative of the absolute concentration of a chemical component, the relative abundance between the components is maintained, and can be calculated. If all sample components are accounted for, the scores for each component can be normalized to unity, and a statistical assessment of the relative abundance of the components made. 

The group mind of termites is a machine for forming statistical assessments after sensing the surrounding environment. Perhaps termites find answers to their lives questions in the same way a computer determines statistical outcomes given a variety of input, or the way that our brains neurons collectively come to decisions as a result of chemically weighting a variety of input signals. 

Proficiency Testing of Analytical Laboratories Organisational and Statistical Assessment , Analyst Cambridge, 1992, 117, 97. 

MG Scanlon, PKW Ng, DE Lawless, W Bushuk. Suitability of reversed-phase high-performance liquid chromatographic separation of wheat proteins for long-term statistical assessment of breadmaking quality. Cereal Chem 67 395-399, 1990. 

EL Lentz, J Chung. Determination of sulfadimethoxine withdrawal time from milk. Part II Statistical assessment. J AOAC lnt 78 371-379, 1995. 

ASTM D-6708. Standard Practice for Statistical Assessment and Improvement of the Expected Agreement Between Two Test Methods that Purport to Measure the Same Property of a Material. 

The typical user of an SRM performs a measurement of the certified property using the apparatus in his laboratory. He compares his result with the certificate value and, if his measurement fails to reproduce the certified value within acceptable limits of precision he investigates his measurement system to remove sources of bias. There are numerous examples of measurement systems in which the level of agreement among measured results by employing SRM s in this way, and the statistical assessment of the performance of measurement systems employing SRM s is a well-established science (3). 

Fig. 15.11 Statistical performances (above) and ROC curves (below) of hypothesis 1 (left) and hypothesis 2 (right). The 17 compounds used for the statistical assessment are those from the training set whereas the 21 compounds used to plot the ROC curves...

Simeonova, P. 2007. Multivariate statistical assessment of the pollution sources along the stream of Kamchia River, Bulgaria. Ecol. Chem. Eng. 14 867-874. 

Absolute limits cannot be used in statistical assessments of compliance based on sampling such standards need to be translated into percentiles to be used. The reasons for this are that standards are usually set in a precautionary manner, and it is nearly always the case that occasional exceedances of a limit value are acceptable. With such an absolute limit, the risk of reporting failure is strongly influenced by sampling frequency the more sampling, the higher the likelihood that at least 1 sample will fail. This is an important consideration if compliance assessments are to be used to compare regions or nations in a way that has serious implications for poor performers. 

The definition of the summary statistic (in this case, the 95th percentile) leads to the option of — or opportunity for — a statistical assessment of compliance and so provides the facility to estimate the standard error in this estimate and the statistical confidence of failure. This is crucial because compliance is assessed by taking samples, a process associated with high errors and the consequent risk of misdirected action. 

Having put into perspective what an LEER is, how it is derived, and what types of statistical assessments are used to assess its validity, we now provide some additional, detailed background information one would need to be able to carry out such an analysis successfully. 

Acceptance criteria Lists pass or fail requirements Enumerates the release acceptance requirements Stipulates the number of required replicate determinations Establishes the statistical assessment requirements... 

Each of the factors on the right side of Eq. (8.16) reflects a statistical assessment of the possibilities for insertion of a single monomer. 

---