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(computer science)
A computer operation in which two numbers are compared as to identity, relative magnitude, or sign.



comparing a gauge or quantity to be measured with a quantity that is reproducible in the measuring process.

Comparisons are made by instruments such as the equal-arm balance, the electric potentiometer, the photometer bench with a photometer, and the comparator for linear standards.



an act of thought by means of which the content of being and cognition is classified, ordered, and evaluated; in comparison, the world is understood to be “coherent” diversity. The act of comparison consists of the pairing of objects for the purpose of clarifying their relationship. Essential to this are the conditions, or bases, of comparison—the attributes that determine precisely what the possible relationships are between objects.

Comparison has meaning only in an aggregate of “homogeneous” objects that form a class. The comparability of objects in a class (tertium comparationis) is realized in terms of the attributes essential for a particular examination; objects comparable in terms of one basis may be incomparable in terms of another. For example, all people are comparable in terms of age, but not all are comparable with respect to “being older.”

The simplest and most important type of relationships revealed by means of comparison are the relationships of identity (equality) and difference. Comparison of this type leads in turn to the concept of universal comparability, that is, the notion that it is always possible to answer the question of whether objects are identical or different. Objects of visual experience are always comparable, although the condition of visibility, or observability, is a significant restriction. In theory, the visual comparison of objects is often impossible, and to compare objects it is necessary to resort to inferences and, eventually, to certain abstractions from which the inferences have been deduced. The supposition of universal comparability is therefore sometimes called the abstraction of comparability. As a rule, the abstraction of comparability is a nontrivial hypothesis and is valid within the framework and on the basis of the main principles of theory.

M. M. NOVOSELOV [24–1047–1; updated]

References in periodicals archive ?
In the face of these challenges, researchers may opt to select a subset of untreated units as a more appropriate comparison group. For instance, a study of Medicaid expansion prior to the Affordable Care Act identified comparison states as those that neighbored expansion states and were most similar with respect to population and demographic characteristics (Sommers, Katherine, and Epstein 2012).
The incidence densities of stroke, ischemic stroke, hemorrhagic stroke, and all-cause mortality were 494.7, 430.6, and 62.2 per 10000 years in the RVO group, which was higher than the corresponding values of 361.6, 317.0, and 46.6 per 10000 years in the PS-matched comparison group (all p < 0.0001).
The mean ([+ or -] standard deviation) of the total difficulties score in the epilepsy group was considerably higher than that in the comparison group (17.5 [+ or -] 6.8 vs.
50 cases with acrochordons was finally included and 50 age-sex matched individuals who did not have acrochordons, but had come to the Department of Dermatology with other skin problems were included in the comparison group.
We also assess the robustness of our estimates to alternative comparison groups based on education.
From the statistical formulae, the standard deviations [[sigma].sub.DA] and [[sigma].sub.DB] are equal to 0.410 and 1.253, respectively, of the two QP-difference comparison groups for 2 Mbps-to-1.5 Mbps and 1.5 Mbps-to-1 Mbps.
Therefore, a substantial age difference between the Aboriginal and non-Aboriginal healthy comparison groups precluded direct comparisons between the CRF groups and the large cohort groups.
The significant Group x Moment interaction showed that, at M1, the children from the intervention and comparison groups had the same level of performance in planning, F(1, 43) = 2.032, p>.05, [[eta].sup.2.sub.p] = .045.
Most published studies that move beyond the impressionistic are limited by small samples, short-term exposure to the arts, self-report measurement bias, or lack of a comparison group. For example, an assessment of a California music program used in-depth interviews with six ex-offenders who had been students in the program (Brewster, 2010).
According to results of Model 1 that included both the intervention and comparison groups, the difference in the number of errors made in the pre and post-intervention assessments for the comparison group, on average, was 3.7 errors; however, the result was not statistically significant (p=0.61), indicating that participants in the comparison group did not reduce the number of errors after the intervention significantly.
We also found that our experimental design did not obviously affect gait measures between exercise and comparison groups, only exhibiting some differences in reaction time measurement.
To measure the effectiveness of the intervention, a researcher, blind to the condition of each of the 24 teachers, observed all of the teachers (both the experimental and the comparison groups) in September to October and April to May of the school year.

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