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Previous work in our group had shown the power of self-organizing neural networks for the projection of high-dimensional datasets into two dimensions while preserving clusters present in the high-dimensional space even after projection [27]. In effect, 2D maps of the high-dimensional data are obtained that can show clusters of similar objects. [Pg.193]

The quality may suffer from the presence of so-called outliers, i.e., compounds that have low similarity to the rest of the dataset. Another negative feature may be just the contrary the dataset may contain too many too highly similar objects. [Pg.205]

Another misleading feature of a dataset, as mentioned above, is redundancy. This means that the dataset contains too many similar objects contributing no... [Pg.206]

The aim of cluster analysis is to group together similar objects. [Pg.508]

Another publication produced by the Center for Chemical Process Safety, Guidelines for Investigating Chemical Process Incidents (CCPS, 1992d), is directed at achieving similar objectives but from a differing perspective and with differing emphasis. Both sources of information can be used in a complementary manner to improve the quality of data collection and incident analysis in the CPI. [Pg.247]

Instead ef the name metathesis, the term disproportionation is frequently applied to the reaction, and sometimes the term dismutation. For historical reasons the name disproportionation is most commonly used for the heterogeneously catalyzed reaction, while the homogeneously catalyzed reaction is usually designated as metathesis. The name disproportionation is correct in the case of the conversion of acyclic alkenes according to Eq. (1) however, this name is inadequate in most other situations, such as the reaction between two different alkenes, and reactions involving cycloalkenes. Similar objections apply to the name dismutation. The name metathesis is not subject to these limitations and, therefore, is preferred. [Pg.132]

Clinical trials are costly to conduct, and results are often critical to the commercial viability of a phytochemical product. Seemingly minor decisions, such as which measurement tool to use or a single entry criterion, can produce thousands of dollars in additional costs. Likewise, a great deal of time, effort and money can be saved by having experts review the study protocol to provide feedback regarding ways to improve efficiency, reduce subject burden and insure that the objectives are being met in the most scientifically sound and cost-effective manner possible. In particular, I recommend that an expert statistician is consulted regarding sample size and power and that the assumptions used in these calculations are reviewed carefully with one or more clinicians. It is not uncommon to see two studies with very similar objectives, which vary by two-fold in the number of subjects under study. Often this can be explained by differences in the assumptions employed in the sample size calculations. [Pg.248]

Other companies have developed various types of computerized systems to achieve similar objectives. It should be pointed out here that the COHESS project was started in Diamond Shamrock in 1973, three years before TSCA became law. Thus, it is difficult to say that it was developed in response to TSCA. It does, however, respond to many of the recordkeeping requirements in TSCA. [Pg.130]

Each object or data point is represented by a point in a multidimensional space. These plots or projected points are arranged in this space so that the distances between pairs of points have the strongest possible relation to the degree of similarity among the pairs of objects. That is, two similar objects are represented by two points that are close together, and two dissimilar objects are represented by a pair of points that are far apart. The space is usually a two- or three-dimensional Euclidean space, but may be non-Euclidean and may have more dimensions. [Pg.948]

While other applications, such as firewalls and anti-virus software, share similar objectives with network intrusion systems, network intrusion systems provide a deeper layer of protection beyond the capabilities of these other systems because they evaluate patterns of computer activity rather than specific files. [Pg.211]

Exploratory data analysis has the aim to learn about the data distribution (clusters, groups of similar objects). In multivariate data analysis, an X-matrix (objects/samples characterized by a set of variables/measurements) is considered. Most used method for this purpose is PCA, which uses latent variables with maximum variance of the scores (Chapter 3). Another approach is cluster analysis (Chapter 6). [Pg.71]

Casassa [155] but is different from 0.625 for hard spheres. These two results suggests quite generally for self-similar objects... [Pg.181]

Let us assume that Mr. Z does indeed have leukemia. For many conditions claimed by plaintiffs, especially those that are highly subjective in nature (headaches, nausea, intermittent skin rashes, insomnia, muscle pain), a similarly objective diagnosis may not be possible this creates many problems in causation evaluation which we shall not try to cope with here. But to evaluate the likelihood that Mr. Z s leukemia was caused by one or more water contaminants, it will be necessary to determine whether there is evidence in the scientific literature that is sufficient to establish a causal link (in the sense, for example, described by lARC and discussed in Chapter 6) between exposure to any one of those contaminants and leukemia. This evaluation is referred to as an analysis of general causation. Thus, it is directed at the question of whether one or more of the chemicals to which Mr. Z was exposed is known, in a general sense, to be a cause of leukemia. If benzene is, for example, one of the chemicals found in Mr. Z s well, and it can be established that he consumed water containing benzene, then we could conclude that general causation is established. [Pg.277]

Since similar objects should be relatively close to each other... [Pg.108]

Precision is the closeness of agreement between indications or measured quantity values obtained by replicate measurements on the same or similar objects under specified conditions. [Pg.224]

Trueness The closeness of agreement between the average of a infinite nimber of replicate measure quantity values and a reference quantity value [VIM] Precision closeness of agreement between indications ormeasLFed quantity values obtained by replicate measurements on the same or similar objects under specified conditions [VIM]... [Pg.230]


See other pages where Similar objects is mentioned: [Pg.193]    [Pg.313]    [Pg.507]    [Pg.372]    [Pg.749]    [Pg.998]    [Pg.513]    [Pg.8]    [Pg.24]    [Pg.69]    [Pg.687]    [Pg.5]    [Pg.26]    [Pg.281]    [Pg.232]    [Pg.9]    [Pg.14]    [Pg.222]    [Pg.13]    [Pg.45]    [Pg.66]    [Pg.98]    [Pg.98]    [Pg.99]    [Pg.131]    [Pg.265]    [Pg.151]    [Pg.300]    [Pg.110]    [Pg.429]    [Pg.7]    [Pg.521]   
See also in sourсe #XX -- [ Pg.301 ]




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