Relative mean deviation

Measurement of the Spectral Intensity For measurement, we use the residual 360 nm peak as internal reference (23). The fluorescence intensity is recorded in the standard method at 430 nm. Fluorescence index is defined by us as the ratio 1430/1350 This is measured at every sampling period for both the blank, the control without antioxidant, and the antioxidant-treated sample. Relative mean deviation of replicate measurements (repositioning the plate) is +5%. 

In the past, a few methods for estimating the liquid viscosity have been proposed, like the group contribution method of Orrick/Erbar [32], Sastri and Rao [69, 70], or van Velzen et al. [71]. They can hardly be recommended, as their application is not easy and their results are often doubtful. For instance, the van Velzen method, often regarded as the most reliable one, produced a relative mean deviation of 92.8% in a benchmark with 670 components [72]. Although data points for the liquid viscosity often widely scatter and deviations can be easier tolerated than for the thermal properties, this value indicates that a lot of components, probably those which were not in the training set, are described poorly. 

A new group contribution method developed by Rarey and Nannoolal [72] performs significantly better. Its relative mean deviation turned out to be 15.3% for 813 components. The method is defined by the following equation ... 

Casual examination of Table IX suggests that differences between Kx and Xexp are not unequivocal. The values of Xexp for the tri-p-chloro compounds, and for the mono m-chloro compound as well, are, however, less reliable than for the other compounds of Tables VII-IX because they are so weak electrolytes that the Shedlovsky method must be supplemented by additional approximations (cf. ref. 74). Thus the apparent superiority of adherence of Xexp for p-chloro substituents to eq. (12) must be disregarded. For m-phenyl substituents the relative mean deviation from constancy of (l/n)log (Xexp)n/ (X exp)o is about three times the relative mean deviation of the corresponding function of Kx. In addition, the former quantities show the expected trend. 

Manganese, D. of - continued with magnesium and zinc, (ti) 334 Mannitol 299, 581 Masking agents 12, 312 Mass action law 16 applications to electrolyte solutions, 23 Matrix effects 733, 794 Maxima in polarography 597 suppression of, 597, 611 Mean deviation 134 relative, 134 standard, 134 Measuring cylinders, 87 flasks, 81... 

Reductant equivalent weights of, 847 Reduction 409 by chromium(II) salts, 409 by hydrogen sulphide, 416 by Jones reductor (zinc amalgam), 410 by liquid amalgams, 412 by silver reductor, 414 by sulphurous acid, 416 by tin(II) chloride, 415 by titanium(II[), 410 by vanadium(II), 410 see also Iron(III), reduction of Reduction potentials 66 Reference electrodes potentials, (T) 554 Relative atomic masses (T) 819 Relative error 134 mean deviation, 134... 

Fig. 5.17. Time domain CARS of nitrogen under normal conditions. Points designate experimental data, solid line calculation with a = 6.0 A, b = 0.024, c = 0.0015. The insert depicts the dependences of the relative mean-square deviation on each of the parameters , b and c, the other two being fixed at their optimum values. The deviations are expressed as percentage of optimum parameters.

RSD, relative standard deviation = (standard deviation/mean) x 100. Deviation = [(mean — nominal)/nominal] x 100. 

Notice that a result of this type, in order to be interpretable, must comprise three numbers the mean, the (relative) standard deviation, and the number of measurements that went into the calculation. All calculations are done using the full precision available, and only the final result is rounded to an appropriate precision. The calculator must be able to handle >4 significant digits in the standard deviation. (See file SYS SUITAB.xls.)... 

Since a series of t-tests is cumbersome to carry out, and does not answer all questions, all measurements will be simultaneously evaluated to find differences between means. The total variance (relative to the grand mean xqm) is broken down into a component Vi variance within groups, which corresponds to the residual variance, and a component V2 variance between groups. If Hq is true, Vi and V2 should be similar, and all values can be pooled because they belong to the same population. When one or more means deviate from the rest, Vj must be significantly larger than Vi. 

Overfilling according to given equations becomes necessary if the experimental relative standard deviation (CV) exceeds 3% resp. 4.5%. Since a filling error of Sx 0.75 g ( 3.75%) is associated with the equipment in question, the regulations require a minimal mean fillweight of 20.00 + 1.645 5 , - 0.05 20.00 = 20.23 g 20.35 g was chosen so that a margin of error remains for the line-operators when they adjust the volumetric controls. 

LABORATORY N MEAN STANDARD DEVIATION RELATIVE STANDARD DEVIATION... 

Figure 5. Minimum and maximum mean TCDD concentrations and relative standard deviations.

The limit of determination [or limit of quantitation (LOQ)] is defined in Directive 96/46/EC as the lowest concentration tested at which an acceptable mean recovery (normally 70-110%) and acceptable relative standard deviation (normally <20%) are obtained. The specific requirements for LOQ in crops, food, feed, soil, drinking and surface water, air, body fluids, and tissues are described in Section 4. Because the abbreviation LOD usually means limit of detection rather than limit of determination, the authors prefer not to use this abbreviation here in order to avoid confusion, and LOQ is used throughout. According to Directive 96/46/EC no data with regard to the limit of detection must be given. 

Confirmation of the results by at least one independent laboratory Lowest concentration at which an acceptable mean recovery is obtained with a relative standard deviation <20%... 

Most pharmacopoeias include a simple weight test on a specified number of tablets that are weighed individually. The arithmetic mean weight and relative standard deviation (i.e., mean divided by standard deviation) of these tablets is then calculated. Only a specified number of test tablets may lie outside the prescribed limits. These specifications vary depending upon the type of tablet and amount of active present. 

Content uniformity is a USP test is designed to establish the homogeneity of a batch. Ten tablets are assayed individually after which the arithmetic mean and relative standard deviation (RSD) are calculated. USP criteria are met if the content uniformity lies within 85-115% of the label claim and the RSD is not greater than 6%. Provision is included in the compendium for additional testing if one or more units fail to meet the standards. 

The discrete Poisson distribution is only characterized by one parameter, the mean Y. The standard deviation is given by sY = Jy and the relative standard deviation by SyreI = 1 / JY. 

Cheng et al. reported the use of a synchronous fluorimetric method for the determination of primaquine in two-component antimalarial tablets [31]. Ground tablets were dissolved in water and the mixture was filtered. The fluorescence intensities of chloroquine phosphate and primaquine phosphate, in the filtrate, were measured at 380 nm (excitation at 355 nm) and 505 nm (excitation at 480 nm), respectively. The calibration graphs were linear from 1 to 8 pg/mL of chloroquine phosphate and 10 to 110 pg/mL of primaquine phosphate. The mean recoveries were 98.2-101.49% and the relative standard deviations were 2.23%. 

Sole use of the correlation coefficient (r) alone is not recommended as a means to demonstrate linearity. The correlation coefficient describes the relation between two random parameters, and shows no relevance for the analytical calibration [31]. The correlation coefficient does not indicate the linearity or lack thereof, unless r exceeds 0.999 [8, 32, 33]. If the value of r is less than 0.999, other parameters such as Vxo, Xp value, ANOVA linear testing, etc., should be calculated. Ebel [34] described using the transformation of r (i.e., Vu ) for expressing the degree of linearity, where the acceptance value of (1 — r ) should be less than 0.05. Camag (Muttents) described the sdv parameter (i.e., the relative standard deviation of the calibration curve) for expressing the linearity of a calibration curve for TLC/HPTLC in its CATS software, and can be calculated as follows ... 

Figure 5. Relative standard deviation on the fitting of the deposition rate of the unattached daughters (Xun) and on the fitting of the ventilation rate (Xvent)> calculated by means of a Monte- Carlo simulation model. The lower curve is obtained with counting statistics alone. The upper curve includes one hour time fluctuations on the input parameters, with 10% rel. stand, dev. on X, un (15/h), a(.35/h), Vent(.45/h) and radon cone. (50 bq/m ) and 2% on recoil factor (.83), penetration unattached (.78) and flow rate (28 1/min).

Statistical analysis One hundred microspores were analysed per slide. Counting was done in four or five replicates (the number of Petri dishes per treatment). Results were expressed as mean SEM (SEM shown graphically in figures). The relative standard deviation (RSD) was 5-6% (n = 400-500 microspores per one variant P =0.95). 

Relative measures of the spread of data are often used, particularly where, for example, the spread of results seems to increase with analyte concentration. The relative standard deviation (RSD) is a measure of the spread of data in comparison to the mean of the data ... 

For the data set given in Table 6.2, calculate the mean, sample standard deviation, relative standard deviation, degrees of freedom and the 95% confidence interval for the mean. 

Coefficient of variation The ratio of the standard deviation to the mean often expressed as a percentage (see also Relative standard deviation). 

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