Use Of Relative Measures Research Articles

Terrorism Determinants, Model Uncertainty and Space in Colombia

ABSTRACT This paper studies the determinants of terrorism at the sub-national level in Colombia during 2001–2014. In order to establish robust relationships, a Bayesian model averaging framework has been implemented using departmental data. We find that the violence suffered by this country is linked to economic factors, especially labor market outcomes. The results obtained are not significantly altered by the use of relative measures of terror, the specification of alternative parameters and model priors or the presence of spatial dependence. The main conclusion drawn from our analysis is that an appropriate strategy to fight against terrorism in similar contexts is to increase its opportunity cost. This might be achieved through the promotion of inclusive socioeconomic development, primarily in rural areas.

Relationships Between Measures of Functional and Isometric Lower Body Strength, Aerobic Capacity, Anaerobic Power, Sprint and Countermovement Jump Performance in Professional Soccer Players.

The purpose of this study was to assess a wide range of physiological and performance variables and investigate whether and to what extent these variables are associated with each other in soccer. Twenty-five male soccer players (25.1 ± 4.56 years; body mass, 75.2 ± 5.92 kg; body height, 180.6 ± 5.45 cm) performed: 5- and 30-m sprints (T5m and T30m, respectively), 1-repetition-maximum (1RM) half squat, maximal voluntary isometric contraction (MVIC) of the knee extensors, countermovement jump (CMJ) to obtain vertical jump height (CMJheight) and power output (CMJpower), the 10-s Wingate Anaerobic Test (WAnT) to obtain peak power (Pmax), and the 20-m multi-stage shuttle run test (MST) to evaluate aerobic capacity. 1RM, MVIC, and Pmax were normalized to body mass. Large negative correlations were found between sprint times and 1RM half back squat/BM (r = -0.510 to -0.570, r2 = 0.260–0.325, both p < 0.01) and Pmax/BM (r = -0.501, r2 = 0.251, p < 0.01). T30m most strongly and negatively correlated with CMJheight (r = -0.744, r2 = 0.554, p < 0.001). WAnT-determined Pmax showed a very large correlation between absolute Pmax and knee-extensor MVIC (r = 0.827, r2 = 0.684, p < 0.001) and large correlations between absolute Pmax and 1RM half squat (r = 0.674, r2 = 0.454, p < 0.001) and CMJpower (r = 0.579, r2 = 0.335, p < 0.01). We also identified a large inverse relationship between CMJheight and T30m (r = -0.744, r2 = 0.554, p < 0.001) and large positive correlation between CMJheight and MVIC/BM (r = 0.702, p < 0.001). The results demonstrate that elite soccer players with greater lower body strength (quantified by the MVIC of the knee extensor and the 1RM half squat) show better sprint and CMJ performance, suggesting the incorporation of soccer-specific resistance training to develop lower body musculature and therefore maximize sprinting ability. The higher correlation coefficients found between T30m and the physiological and athletic measures compared with T5m promote the use of this sprint distance when assessing performance. The use of relative measures (normalized to body mass) is advisable when comparing strength variables with sprint and CMJ performance or anaerobic power. Considering the correlations of WAnT-determined Pmax versus CMJpower, coaches should administer tests that assess jumping and linear sprint performance rather than the cycling-specific WAnT.

Travel intention: Relative value of transport alternatives

Abstract The objective was to test the Theory of Planned Behavior and the proposition that relative measures should be used in travel mode choice situations. Data from a survey in Norway was analyzed using regression analysis. The results indicated that factors of the Theory of Planned Behavior and past behavior predicted intentions to travel by car, public, transport, bicycle, and on foot. The results supported the idea that there is a split in perceived behavioral control in controllability and self-efficacy, as controllability was a significant predictor only for intention to travel by car. The use of relative measures added to the predictive strength of all predictors and increased prediction of behavioral intention for all travel modes. The results supported the Theory of Planned Behavior and the proposition regarding choice situations. Previous tests of the theory may have underestimated its predictive power. Attitudes, subjective norms, and perceived behavioral control predict travel intentions and may be targeted in interventions aimed at promoting travel mode choice.

RUBIN ET AL. RESPOND

King et al. are concerned about our use of relative measures to gauge progress toward health equality in HIV mortality. Prior work by some of these same authors suggests,1 and we concur, that values and moral issues are involved and that explicit consideration of these is essential. Their comment is useful as it spurs us to think more deeply and provides an opportunity to report why, in this situation, relative measures more adeptly address moral concerns. To begin, consider a situation in which human knowledge concerning how to prevent or treat a disease is absent. We may find absolute or relative differences between groups but, as a society, we bear no culpability for these differences, as we cannot do anything about them. However, when we develop knowledge, our moral responsibility grows in proportion to our capacity to control disease and death. Once we gain a certain level of mastery, we bear responsibility for the consequences our actions have on patterns of human health.2 This simple but compelling moral standpoint is what leads us to prefer relative over absolute measures in the situation we studied.3 To understand, imagine a circumstance in which mortality rates for a disease are declining precipitously as a result of an advance in human knowledge. Imagine also that the absolute gap between an advantaged and a disadvantaged group remains constant over time. According to our moral argument, a gap of the same magnitude becomes more problematic as we gain control over the disease—it is more completely our responsibility. An absolute measure (rate difference) fails to reflect this moral position, suggesting instead that health inequalities remained constant over time. A relative measure, by contrast, coheres with our moral stance by showing a growing rate ratio over time. It correctly indicates that an absolute gap of the same magnitude becomes more morally reprehensible as we gain control. King et al. have done us a service by identifying problems in the interface between measures of health inequality and the moral and ethical issues that surround them. However, we found little guidance in their statements with respect to how to move toward solutions to the philosophical issues they identify, thereby necessitating a very modest de novo attempt on our part. Thus, while King et al.’s insights have utility for identifying problems and thereby facilitating a kind of policing of health inequalities researchers to ensure acknowledgment of those problems, providing a well-reasoned set of ethical principles connected to these problems is an issue that still lies before us.

Use and misuse of correspondence analysis in codon usage studies.

Correspondence analysis has frequently been used for codon usage studies but this method is often misused. Because amino acid composition exerts constraints on codon usage, it is common to use tables containing relative codon frequencies (or ratios of frequencies) instead of simple codon counts to get rid of these amino acid biases. The problem is that some important properties of correspondence analysis, such as rows weighting, are lost in the process. Moreover, the use of relative measures sometimes introduces other biases and often diminishes the quantity of information to analyse, occasionally resulting in interpretation errors. For instance, in the case of an organism such as Borrelia burgdorferi, the use of relative measures led to the conclusion that there was no translational selection, while analyses based on codon counts show that there is a possibility of a selective effect at that level. In this paper, we expose these problems and we propose alternative strategies to correspondence analysis for studying codon usage biases when amino acid composition effects must be removed.

Word Length and Vowel Duration in Apraxia of Speech: The Use of Relative Measures

Previous research has established that the duration of stressed word stem vowels is shorter in polysyllabic words than in monosyllabic words for normal speakers and for speakers with aphasia and apraxia of speech (AOS). However, the results are inconsistent across studies with regard to the magnitude and pattern of the duration reduction for apraxic speakers. We hypothesized that this inconsistency may be explained based on different relative measures of duration reduction. A speech sample was obtained from 10 aphasic speakers with AOS, 10 aphasic speakers without AOS, and 10 normal controls. As predicted, the use of two different relative measures resulted in different vowel reduction patterns, both of which were consistent with previous reports. The results further indicate that the production of polysyllabic words is particularly taxing in AOS and is associated with a substantial reduction of speaking rate compared to other aphasic and normal speakers.

Use of methodological diversity to improve neural network generalisation

Littlewood and Miller [4] present a statistical framework for dealing with coincident failures in multiversion software systems. They develop a theoretical model that holds the promise of high system reliability through the use of multiple, diverse sets of alternative versions. In this paper, we adapt their framework to investigate the feasibility of exploiting the diversity observable in multiple populations of neural networks developed using diverse methodologies. We evaluate the generalisation improvements achieved by a range of methodologically diverse network generation processes. We attempt to order the constituent methodological features with respect to their potential for use in the engineering of useful diversity. We also define and explore the use of relative measures of the diversity between version sets as a guide to the potential for exploiting interset diversity.