Error range

An analytical method for the prediction of compressed liquid densities was proposed by Thomson et al. " The method requires the saturated liquid density at the temperature of interest, the critical temperature, the critical pressure, an acentric factor (preferably the one optimized for vapor pressure data), and the vapor pressure at the temperature of interest. All properties not known experimentally maybe estimated. Errors range from about 1 percent for hydrocarbons to 2 percent for nonhydrocarbons. 

The measurements are also subjec t to systematic errors ranging from sensor position, sampling methods, and instrument degradation... 

We computed the percentage errors between the reaction rate computations based on the experiments with those based on the kinetic model. Note that, like the pressure and temperature comparisons, the accuracy of the calculations for reaction rates decreases as we compare Test 1 with Test 2 and Test 3- In Test 1 the error ranges from 3 to 21, in Test 2 it was 10 to 21, in Test 3 it ranged from 5 to 36. ... 

Figure 7. Vapor-Uquid-soUds (plastic crystal 2, plastic crystal 2, crystal 3) phase diagram of diamantane. This diagram is based on the data of Table II. The shaded area between vapor and plastic crystal 2 and crystal 3 phase transitions is indicative of the error range of the available data.

Considering all potential experimental and systematic errors of NOE/ROE crosspeak intensities, it is remarkable how robust the derived distance restraints still are. The reason Ues in the dependence of the cross-relaxation rate even if a cross-peak intensity is determined wrongly by a factor 2, the resulting distance restraint is only affected by the factor 1.12, which usually lies within the error range of distance restraints used in structure calculations. It should be further noted that the quaUty of a resulting structure is not so much determined by the... 

Table 8-7. Frequency scaling factors, rms deviation, proportion outside a 10 % error range and listings of problematic cases [cm-1] for several methods employing the 6-31G(d) basis set. Taken from Scott and Radom, 1996.

The minimum uncertainty (ca. 3%) of photometric error ranges from approximately 20 to 60% transmittance or an absorbance range of 0.2-0.7, a 5% relative error in concentration has a photometric range of 0.1-1.0. 

Note Mass accuracy is highly dependent on many parameters such as resolving power, scan rate, scanning method, signal-to-noise ratio of the peaks, peak shapes, overlap of isotopic peaks at same nominal mass, mass difference between adjacent reference peaks etc. An error of 5 mmu for routine applications is a conservative estimate and thus the experimental accurate mass should lie within this error range independent of the ionization method and the instrument used. [37] There is no reason that the correct (expected) composition has to be the composition with the smallest error. 

The value of this work is to illustrate the importance of including the estimated amount interval with every calculated amount estimate in written reports. These can be calculated at any response level. As an illustration of this process we can use the data of Table XIII. If an analysis of fenvalerate were being performed and the standards were those of Dataset A, an amount estimated to be 1.5 ng would be reported as having a total error range of 1.16 to 1.97 ng or in rounded figures 1.2 to 2.0 ng. 

Of the five group-13 elements, only B and A1 have experimentally well characterized electron affinities. Lists of recommended EAs [50,51] show errors ranging from 50% to 100% for Ga, In, and T1. Very few calculations have appeared for the latter atoms. These include the multireference configuration interaction (MRCI) ofAmau etal. using pseudopotentials [52], our relativistic coupled cluster work on T1 [45], and the multiconfiguration Dirac-Fock (MCDF) computation of Wijesundera [53]. 

PIO We speculate that, due to structural variations, some unavoidable signal loss may be structure dependent and an error range of 10-20% is possible. (Yan et ab, 2007)... 

Volume of distribution predicted from tissue composition-based equations showed an average fold error of 2.2 and the correlation of predicted versus observed volume for the five compounds was poor. For the prediction of volume of distribution it was assumed that the volume in human (L/kg) was the same as the observed volume in the rat (ranging from 0.9 to 2.8 L/kg for the five compounds). Due to the uncertainty in the prediction of volume, the error range associated with this parameter was set as a uniform distribution over a twofold range. 

The fact that the total surface area of the particles has virtually no effect within the experimental error range may suggest that the rate-determining step of the overall reaction is not the surface reaction process but a preceding reaction such as the... 

For a trace element concentration to be certified by NBS, it must be determined by at least two independent methods, the results of which must agree within a small experimental error range of 1% to 10%, depending on the nature of the sample and the concentration level of the element. Such accuracy in determining some trace elements for certification of coal SRM is achieved most easily by NAA with radiochemical separation. Scientists at NBS have extensively tested a neutron activation method that involves a combustion separation procedure on coal as well as on several other matrices to be certified as standard reference materials. The procedures they have thus developed to determine mercury (12), selenium (13), and arsenic, zinc, and cadmium (14) are outlined in a following section on methods for determining specific elements in coal. 

REPRODUCIBILITY AND RECOVERY. Three different urine extracts, containing different cholesterol levels, were each analyzed 10 times. The maximum percent error ranged from 0.39 to 1.25% and the standard deviation ranged from 0.785 to 12.368. The average recovery in 13 experiments was 99.5% with a range to 98.44 -100.93%. 

When the constant can be calculated from an experimental data point, the error is typically 2-5%, When no experimental data are available, the error ranges from 4-10%... 

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