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Probability level

The standardized variable (the z statistic) requires only the probability level to be specified. It measures the deviation from the population mean in units of standard deviation. Y is 0.399 for the most probable value, /x. In the absence of any other information, the normal distribution is assumed to apply whenever repetitive measurements are made on a sample, or a similar measurement is made on different samples. [Pg.194]

From Equation 4, x is 77.11 and from Equation 5, is 0.24 for 4 degrees of freedom. Because cr is not known, the Student 975 (2.78 for 4 degrees of freedom) is used to calculate the confidence interval at the 95% probability level. [Pg.199]

The F statistic describes the distribution of the ratios of variances of two sets of samples. It requires three table labels the probability level and the two degrees of freedom. Since the F distribution requires a three-dimensional table which is effectively unknown, the F tables are presented as large sets of two-dimensional tables. The F distribution in Table 2.29 has the different numbers of degrees of freedom for the denominator variance placed along the vertical axis, while in each table the two horizontal axes represent the numerator degrees of freedom and the probability level. Only two probability levels are given in Table 2.29 the upper 5% points (F0 95) and the upper 1% points (Fq 99). More extensive tables of statistics will list additional probability levels, and they should be consulted when needed. [Pg.204]

Statistically, a similar Indication of precision could be achieved by utilising the 95% probability level if the results fell on a "Gaussian" curve, viz., the confidence would lie within two standard deviations of the mean. R 2 x SD = 56.3 24.8... [Pg.362]

The immunorestorative potential of inosiplex has been evaluated in several clinical conditions, including post-surgical trauma, cancer patients with concurrent viral infections, and cancer patients receiving radiotherapy or chemotherapy. For example, most (84%) of the surgery patients remained immunologicaHy depressed, but 56% of the inosiplex-treated surgery patients had complete restoration of normal skin test reactivity (probability level < 0.0005). The use of inosiplex as an adjuvant to chemotherapy or radiotherapy appears to be valuable in the prophylaxis against opportunistic infections. [Pg.36]

FMEA can be used to provide a quantitative measure of the risk for a design. Because it can be applied hierarchically from system through subassembly and component levels down to individual dimensions and characteristics, it follows the progress of the design into detail. FMEA also lists potential failure modes and rates their Severity (S), Occurrence (O) and Detectability ( )). It therefore provides a possible means for linking potential variability risks with consequent design acceptability and associated costs. Note that the ratings of Occurrence and Detectability are equated to probability levels. [Pg.67]

As time goes on, the ultimate resolution of the SEM operated in these modes will probably level out near 1 nm. The major growth of SEMs now seems to be in the development of specialized instruments. An environmental SEM has been developed that uses differential pumping to permit the observation of specimens at higher pressures. Photographs of the formation of ice crystals have been taken and the instrument has particular application to samples that are not vacuum compatible, such as biological samples. [Pg.83]

Failure frequencies of structures, equipment, and piping are related to their acceleration which is related to the ground-motion of the plant s foundation (e.g., the peak ground acceleration). For PSA, it is useful to present the seismic hazard at the site as a family of hazard curves with different nonexceedence-probability levels (Figure 5.1-3). By selecting various values of the peak ground acceleration, the acceleration and forces on the plant components may be obtained as described in the following. [Pg.190]

Probability level 4>i 0i (corresponding to greater mean square) ... [Pg.841]

Figure 5 shows the joint 95% posterior probability region for the two parameter functions. Shimmer bands are also indicated at the 95% probability level. This analysis confirms the results of Hill et al. that both styrene and acrlyonitrile exhibit a penultimate effect. [Pg.291]

Figure 5.18 (a) Drawing of the [Au(S2CN (C5Hii)2)]2 molecules in DMSO with two repeating units of chains in the structure viewed perpendicular to the stacking axis. Thermal ellipsoids are drawn at the 50% probability level. The pentyl moieties have been omitted forclarity. [Pg.268]

Parameter estimates are tested on whether they differ significantly from zero at a certain probability level. If not, the parameter should be skipped from the model and the model should be redefined even if the test for model adequacy was positive. When the errors have constant variance, the random variable... [Pg.547]

Confidence limits for the parameter estimates define the region where values of bj are not significantly different from the optimal value at a certain probability level 1-a with all other parameters kept at their optimal values estimated. The confidence limits are a measure of uncertainty in the optimal estimates the broader the confidence limits the more uncertain are the estimates. These intervals for linear models are given by... [Pg.547]

For linear models the joint confidence region is an Alp-dimensional ellipsoid. All parameters encapsulated within this hyperellipsoid do not differ significantly from the optimal estimates at the probability level of 1-a. [Pg.548]

The sampling variance of the material determined at a certain mass and the number of repetitive analyses can be used for the calculation of a sampling constant, K, a homogeneity factor, Hg or a statistical tolerance interval (m A) which will cover at least a 95 % probability at a probability level of r - a = 0.95 to obtain the expected result in the certified range (Pauwels et al. 1994). The value of A is computed as A = k 2R-s, a multiple of Rj, where is the standard deviation of the homogeneity determination,. The value of fe 2 depends on the number of measurements, n, the proportion, P, of the total population to be covered (95 %) and the probability level i - a (0.95). These factors for two-sided tolerance limits for normal distribution fe 2 can be found in various statistical textbooks (Owen 1962). The overall standard deviation S = (s/s/n) as determined from a series of replicate samples of approximately equal masses is composed of the analytical error, R , and an error due to sample inhomogeneity, Rj. As the variances are additive, one can write (Equation 4.2) ... [Pg.132]

Once the standard error of estimate of the mean forecasted response has been estimated, i.e., the uncertainty in the total production rate, one can compute the probability level, a, for which the minimum total production rate is below some pre-determined value based on a previously conducted economic analysis. Such calculations can be performed as part of the post-processing calculations. [Pg.388]

Figure 1. ORTEP plot of LR-B/081 at 18 K. Ellipsoids at 95% probability level. H atoms are omitted for clarity. Figure 1. ORTEP plot of LR-B/081 at 18 K. Ellipsoids at 95% probability level. H atoms are omitted for clarity.
Fig. 3. Thermal ellipsoid diagrams for the Z (a) and E (b) isomers of 27, 30% probability level.24... Fig. 3. Thermal ellipsoid diagrams for the Z (a) and E (b) isomers of 27, 30% probability level.24...
The data for the six Israeli arid soils show that Co contents in the easily reducible oxide, the organic matter, the reducible oxide and the residual fractions and the total Co are linearly related to the Mn contents in each respective fraction. Correlation coefficients between the respective Co and Mn fractions are significant at the 5% probability level (Fig. 5.6). The Co/Mn molar ratios are 0.0186, 0.0177, 0.0075, 0.0205, 0.0364 in the total, the easily reducible oxide, the organic matter, the reducible oxide and the residual fractions, respectively. Therefore, Co is more preferentially incorporated in the reducible oxide (Fe oxide) fraction than Mn. Much of the Co in arid soils is included in the easily reducible oxide (Mn oxide) fraction,... [Pg.158]

The earliest records of world annual As production from mining date from 1900 (Kelly et al. 2002) (Fig. 9.1a). World As production from mining increased steeply from 1900 to 1930. The change in production is described by the exponential best-fit equation Y = 63.66 e where Y is world annual As mine production in tons and X is number of years since 1849 (R2 = 0.846, significance at 5% probability level). From 1850 to 1900 and between 1906 and 1909, measured records were not available and they... [Pg.305]

Normally, it is convenient to adjust the critical value to be equidistant from /i0 and yu,a, and then adjust n so that that critical value represents the desired probability levels for a and [3. [Pg.101]

Choose the probability level as alpha (a), as the risk that our measurement value (m) will be off by more than (d)... [Pg.493]

Rohrabacher, D.B. Dixon s Q-Tables for Multiple Probability Levels Analytical Chemistry 63, 139 (1991). [Pg.495]

Fig. 9. Composition (5a, X12 = H 5d, X12 = OCH3) and ORTEP (5a) structures of the black p-oxo-bridged diiron(IV) complex rapidly formed in a high yield from la,d and 02 in CH2C12 or other weakly coordinating solvents. The ellipsoids are drawn at the 50% probability level. From Ref. (38). Fig. 9. Composition (5a, X12 = H 5d, X12 = OCH3) and ORTEP (5a) structures of the black p-oxo-bridged diiron(IV) complex rapidly formed in a high yield from la,d and 02 in CH2C12 or other weakly coordinating solvents. The ellipsoids are drawn at the 50% probability level. From Ref. (38).
Fig. 6. Molecular structures of anti-2 (top), anti,anti-3 (middle), and anti,anti,anti-4 (bottom). Thermal ellipsoids are drawn at the 30% probability level. Fig. 6. Molecular structures of anti-2 (top), anti,anti-3 (middle), and anti,anti,anti-4 (bottom). Thermal ellipsoids are drawn at the 30% probability level.

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Levels of hazard probability

Most probable electron level

Relationship Between Confidence Intervals and Probability Levels

Safety integrity levels probability of failure on demand

Validation Probability level

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