Bias-free

Similarly, some INAA data contributed to the derivation of a reference value for Ba in SDO-i were biased high by an interference from Ru (Wandless 1993). The Ru is a fission product of U, whose concentration of 40 qg/g is relatively high in SDO-1. In this case, no appropriate reference sample was available for analysis to control the SDO-1 results the interference was identified through the disagreement between INAA data and data produced using XRF and ICP-AES methods on the same sample. A bias-free method again resulted when analysis of an atypical type led to detection of a rarely encountered but sizeable spectral overlap. Once identified, correction was straightforward. 

This means that the computation of the optimum estimate of x is effectively decoupled from the estimate of the bias. Moreover, it can be computed in terms of the residuals of the bias-free estimate. In terms of x, this can be expressed as follows ... 

Measured value Estimate with bias Bias-free estimate... 

In some textbooks, a confidence interval is described as the interval within which there is a certain probability of finding the true value of the estimated quantity. Does the term true used in this sense indicate the statistical population value (e.g., p if one is estimating a mean) or the bias-free value (e.g., 6.21% iron in a mineral) Could these two interpretations of true value be a source of misunderstanding in conversations between a statistician and a geologist ... 

The graph is obtained by plotting Y,- against Y, results for each of the ten laboratories. The axes are drawn such that the point of intersection is at the mean values for Y, and 7/. As a single method is used in the trial, the circle represents the standard deviation of the pooled Y and Y data. The plot shows the predominance of systematic error over random error. Ideally, for bias-free data (i.e. containing no systematic error) the points would be clustered around the mid-point with approximately equal numbers in each of the four quadrants formed by the axes. In practice the points lie scattered around a 45° line. This pattern has been observed with many thousands of collaborative trials. 

The issues of relative bias or absolute bias also need consideration. Relative bias is likely to involve comparisons of gross sample results, whereas absolute bias is based on comparison with bias-free reference values and usually involves increment-by-increment comparisons. 

Systematic spacing of increments collected from a stopped belt is accepted universally as the reference method of sampling that is intrinsically bias-free. Stationary sampling, that is, sampling coal at rest in piles, or in transit in trucks, railcars, barges, and ships, suffers decreased reliability to an indeterminate degree. 

Apart from the problem of nonlinearity, the calibration curve approach has another pitfall measured ion abundance ratios can change with time, leading to the possibility of significant errors since the calibration and sample measurements cannot be simultaneous (Schoeller, 1980). In order to minimize the effect of instrumental drift and to optimize precision, the National Bureau of Standards (NBS) proposed a bracketing protocol for the development of definitive (i.e., essentially bias-free and precise) IDMS methods (Cohen et al., 1980 White et al., 1982 Yap et al., 1983). It involves the measurement of each sample between measurements of calibration standards whose ion abundances most closely surround the ion abundance ratio of the sample. Measurements are made according to a strict protocol, used with samples prepared under restrictive conditions ... 

Pu, Q. S., Fang, Z. L., Combination of flow injection with capillary electrophoresis. Part 6. A bias-free sample introduction system based on electroosmotic-flow traction. Anal. Chim. Actfl 1999, 398(1), 65-74. 

Much attention has been directed at job evaluation as both a potential source of bias against women and as a mechanism to reduce bias (Treiman and Hartmann 1981). We will discuss some of the studies of the effects of gender in job evaluation and then consider some recommendations offered to ensure bias-free job evaluation. 

Several recommendations help to ensure that job evaluation plans are bias free (Remick 1984). 

Ensuring that the plan is applied in as bias-free a manner as feasible. This includes ensuring that the job descriptions are bias free, that incumbent names are excluded from the job-evaluation process, and that women are part of the job-evaluation team and serve as evaluators. 

The ellipsometric angles can be determined quite accurately and rather independently on absolute intensity. Several reversal and calibration methods are available so the ellipsometric angles can be obtained accurately and bias-free. 

The HSEQ Assessment Procedure is a practical tool developed to evaluate health, safety, environment and quality management in the supply network of the process and manufacturing industry (Vayrynen et al. 2012). It offers companies an evaluation performed by an outsider and thus, a bias-free reference for companies in the process of comparing and choosing suppliers. These suppliers also have an oppoitunity to ask for an HSEQ Assessment Procedure (later referred to as HSEQ AP) to be carried out for their network s suppliers. 

The second case, 0 = 1, describes bias-free dynamics, which means in the dendrimeric antennae case that the entropic bias is canceled by the energetic bias. 

The bias-free method of performing the statistical averages on individual realizations uses the transit time, t weighting (see George, 1976). Additional information on the transit time weighting method can be found in George (1978), Buchhave et al. (1979), Buchhave (1979), and Benedict and Gould (1999). In the literature, transit time is sometimes referred to as residence time. 

Fermi energy ferroelectric forward bias free electron Hall effect hole... 

We have already found that the estimation of O is bias-free, i.e., its exact average (O) is identical with O) [see Eq, (4,3)]. However, we have also convinced ourselves that variances of sampled data are not free of bias. Combining Eqs. (4,10) and (4.11), we consequently find that the expected value of the simplest nonlinear function of O, AO) = o ... 

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