Precision estimate

The obtained results for the magnetic bench have allowed to note that defects situated at 12 mm of depth have been observed clearly. This is explained by the high power furnished by the bench, in addition its induction is double alternation rectified. Dimensions of the defect (height and width) are precisely estimated (figure 1). The defect detection at this depth is due to the application of a rectified field, so skin phenomenon is almost absent. 

Following the pioneer work of Beebe in 1945, the adsorption of krypton at 77 K has come into widespread use for the determination of relatively small surface areas because its saturation vapour pressure is rather low (p° 2Torr). Consequently the dead space correction for unadsorbed gas is small enough to permit the measurement of quite small adsorption with reasonable precision. Estimates of specific surface as low as 10 cm g" have been reported. Unfortunately, however, there are some complications in the interpretation of the adsorption isotherm. 

While none of these kinds of variances can be precisely estimated you should consider them (and others you identify) in terms of their potential impact, and build an appropriate contingency percentage into estimates of... 

Obviously, agut = a (0) can be calculated with high precision. It happens that the precise estimate is not very accurate because of the large step size, but this can be overcome using a smaller At or a more sophisticated integration technique. An accurate value is Ugut — 0.287. 

More precise estimates come from accurate measurements of isotope ratios. Three pairs of radioactive isotopes and their products are abundant enough for such ratios to be measured ... 

Bowers, 6. N., Jr. Kelley, M. L. and McComb, R. B. Precision estimates in clinical chemistry. I. Variability of analytic results in a survey reference sample related to the use of a non-human serum alkaline phosphatase. Clin. Chem. (1967), 14, 595-607. 

Based on the material presented up to now the steps that need to be followed to design the next experiment for the precise estimation of the model parameters is given below ... 

Equations 13.14 to 13.16 constitute the well known recursive least squares (RLS) algorithm. It is the simplest and most widely used recursive estimation method. It should be noted that it is computationally very efficient as it does not require a matrix inversion at each sampling interval. Several researchers have introduced a variable forgetting factor to allow a more precise estimation of 0 when the process is not "sensed" to change. 

Bioremediation also has its limitations. Some chemicals are not amenable to biodegradation, for instance, heavy metals, radionuclides, and some chlorinated compounds. In some cases, the microbial metabolism of the contaminants may produce toxic metabolites. Bioremediation is a scientifically intensive procedure that must be tailored to site-specific conditions, and usually requires treatability studies to be conducted on a small scale before the actual cleanup of a site.13 The treatability procedure is important, as it establishes the extent of degradation and evaluates the potential use of a selected microorganism for bioremediation. A precise estimate on vessel size or area involved, speed of reaction, and economics can therefore be determined at the laboratory stage. 

When humans contact a chemical residue such as a pesticide on a treated surface, some of the deposit can be dislodged or transferred to skin or clothing. Ultimately, a portion of the amount transferred may be absorbed and constitute the absorbed daily dose (ADD). The ADD provides the most precise estimate of exposure that can be practically obtained for humans and has become the most useful expression of exposure for risk assessment and risk management. 

Both the Chen and Gross [48] and the Gallo et al. [49] methods have been applied to eliminating compartments. Both derivation methods are based on the specific mass balance equations for the given model structure. Monte Carlo investigations have demonstrated that both methods provide reasonably accurate and precise estimates of partition coefficients from concentration-time data sets containing error, data one is likely to encounter from in vivo studies. 

Kremer16 then went on to make a precise estimate of the social value of an innovation or surplus under a situation of competition and under a monopoly. Thus, for example, for a price five times higher than the price fixed according to the marginal price, we detect a static distortion of 1.5, that is, the social rate of return of an innovation in a situation with marginal cost prices will be 1.5 times the return on the investment under monopoly prices. In this situation the social value of an innovation in a competitive environment would be 9.35 times the social value in a monopoly, that is, when there is no welfare loss. Kremer thus provides an estimate of welfare loss from a more thorough analytical perspective, and shows that it can be sizeable. 

H0 If Fs is less than or equal to Ft, then there is NO DIFFERENCE in Precision estimation. 

Precision estimates are key method performance parameters and are also required in order to carry out other aspects of method validation, such as bias and ruggedness studies. Precision is also a component of measurement uncertainty, as detailed in Chapter 6. The statistics that are applied refer to random variation and therefore it is important that the measurements are made to comply with this requirement, e.g. if change of precision with concentration is being investigated, the samples should be measured in a random order. 

Balloon and WMAP satellite missions provide details of angular fluctuation spectrum of MWB, giving precise estimates of cosmological parameters. 

The first heat capacity measurements were performed by Sorai and Seki on [Fe(phen)2(NCX)2] with X=S, Se [45,46]. A few other SCO compounds of Fe(II) [47], Fe(III) [48] and Mn(III) [49] have been studied quantitatively down to very low (liquid helium) temperatures. For a relatively quick but less precise estimate of AH, AS, the transition temperature and the occurrence of hysteresis, DSC measurements, although mostly accessible only down to liquid nitrogen temperatures, are useful and easy to perform [50]. 

In addition, it is important to consider the distributional properties of indicators. The measures should be sufficiently long (have enough levels) to allow for a large number of intervals, which is necessary for precise estimation. A general recommendation is that an indicator should have at least 20 levels (Waller Meehl, 1998). Analyses with shorter measures are possible but produce less interpretable results. Indicator skew is another consideration. One critical feature of an indicator is its ability to separate taxonic and nontaxonic cases (indicator validity). Indicator validity is associated with indicator skew. If the taxon base rate is small (e.g., less than. 30), then an indicator has to have substantial positive skew to be a valid measure of the taxon. Positive skew is necessary but is not sufficient for an indicator to be valid. This relationship does not hold for taxa with base rates around. 50, and it is reversed (negative skew is necessary) for taxa with high base rates. 

Next, the MAXCOV analyses were repeated with smoothed plots (using Tukey s 3RH twice procedure Tukey, 1977). The general shape of the taxonic plots did not change, but the peaks shifted and the base rate estimates lost their cohesion (SD =. 10). It is notable that smoothing had this effect. This would suggest that smoothing can aid in the interpretation of the curves, but the precise estimation of the taxon base rate and location of hitmaxes may be sacrificed. 

All hydrocarbon fire mechanisms and estimates will be affected by to some extent of flame stability features such as varying fuel composition as lighter constituents are consumed, available ambient oxygen supplies, ventilation patterns, and wind effects. Studies into these effects have generally not progressed to the level where precise estimations can be made without scale model tests or on site measurements. 

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