What is central to political belief system networks?

A central challenge for identifying core components of a belief system is xamining the position of components within the structure of the entire belief system. We test whether operational (i.e. positions on issues) or symbolic (i.e. affective attachments to political groups and labels) components are most central by modeling a political belief system as a network of interconnected attitudes and beliefs. Across seven waves of representative panel data from New Zealand, we find that symbolic components are more central than perational components (d’s range 0.78 – 0.97). Symbolic components were also closer than operational components in the network to self-reported voting (d = -2.43), pro-environmental actions (d’s = -1.71 and -1.63), and religious behaviors (d = -0.74). These findings are consistent with perspectives that emphasize the importance of symbolic politics in tying belief systems together and motivating behavior, and further the link between political belief system research and network science. Keywords: Belief systems, networks, ideology, political psycholog

Conservatives moral foundations are more densely connected than liberals’ moral foundations

We use network psychometrics to map a subsection of moral belief systems predicted by moral foundations theory (MFT). This approach conceptualizes moral systems as networks, with moral beliefs represented as nodes connected by direct relations. As such, it advances a novel test of MFT’s claim that liberals and conservatives have different systems of foundational moral values, which we test in three large datasets (N(Sample1) = 854; N(Sample2) = 679; N(Sample3) = 2,572), from two countries (the United States and New Zealand). Results supported our first hypothesis that liberals’ moral systems show more segregation between individualizing and binding foundations than conservatives. Results showed only weak support for our second hypothesis, that this pattern would be more typical of higher educated than less educated liberals/conservatives. Findings support a systems approach to MFT and show the value of modeling moral belief systems as networks

Performance evaluation of digital pulse position modulation for wavelength division multiplexing FSO systems impaired by interchannel crosstalk

Wavelength division multiplexing (WDM) has been proposed for fibre, intersatellite, free space and indoor optical communication systems. Digital pulse position modulation (DPPM) is a more power efficient modulation format than on-off keying (OOK) and a strong contender for the modulation of free-space systems. Although DPPM obtains this advantage in exchange for a bandwidth expansion, WDM systems using it are still potentially attractive, particularly for moderate coding levels. However, WDM systems are susceptible to interchannel crosstalk and modelling this in a WDM DPPM system is necessary. Models of varying complexity, based on simplifying assumptions, are presented and evaluated for the case of a single crosstalk wavelength. For a single crosstalk, results can be straightforwardly obtained by artificially imposing the computationally convenient constraint that frames (and thus slots also) align. Multiple crosstalk effects are additionally investigated, for the most practically relevant cases of modest coding level, and using both simulation and analytical methods. In general, DPPM maintains its sensitivity advantage over OOK even in the presence of crosstalk while predicting lower power penalty at low coding level in WDM systems

Performance evaluation of turbulence-accentuated interchannel crosstalk for hybrid fibre and free-space optical wavelength-division-multiplexing systems using digital pulse-position modulation

A hybrid fibre and free-space optical communication link using digital pulse-position modulation (DPPM) in a wavelength-division-multiplexing system is proposed. Such a system, which could provide a power efficient, robust and flexible solution to high-speed access networks, is a contender for a passive optical network solution and could readily be deployed in areas with restrictions in optical fibre installation, or alternatively as a disaster recovery network. Interchannel crosstalk and atmospheric turbulence are major impairments in such a system and could combine in some cases to degrade the system. Both impairments are investigated here and the results are presented in the form of bit error probability, required optical transmission power and power penalties. Depending on the position of the interferer relative to the desired user, power penalties of about 0.2–3.0 dB for weak turbulence and above 20 dB for strong turbulence regimes are reported for bit error rate of 10−6. DPPM scheme with a coding level of 2 show about 2 dB improvements over on–off-keying scheme

Taxonomic surrogacy in biodiversity assessments, and the meaning of Linnaean ranks

Copyright © 2006 The Natural History MuseumThe majority of biodiversity assessments use species as the base unit. Recently, a series of studies have suggested replacing numbers of species with higher ranked taxa (genera, families, etc.); a method known as taxonomic surrogacy that has an important potential to save time and resources in assesments of biological diversity. We examine the relationships between taxa and ranks, and suggest that species/higher taxon exchanges are founded on misconceptions about the properties of Linnaean classification. Rank allocations in current classifications constitute a heterogeneous mixture of various historical and contemporary views. Even if all taxa were monophyletic, those referred to the same rank would simply denote separate clades without further equivalence. We conclude that they are no more comparable than any other, non-nested taxa, such as, for example, the genus Rattus and the phylum Arthropoda, and that taxonomic surrogacy lacks justification. These problems are also illustrated with data of polychaetous annelid worms from a broad-scale study of benthic biodiversity and species distributions in the Irish Sea. A recent consensus phylogeny for polychaetes is used to provide three different family-level classifications of polychaetes. We use families as a surrogate for species, and present Shannon–Wiener diversity indices for the different sites and the three different classifications, showing how the diversity measures rely on subjective rank allocations.Y. Bertrand, F. Pleijel and G. W. Rous

Evaluation of Running Water Rinsing of Soft Contact Lenses

The safety of using running water to rinse soft contact lenses was evaluated. Twenty soft contact lenses were contaminated with viable micro­organisms in an organic load and were then rinsed under running water for 20-30 seconds. The results showed that the reduction of the contaminants by the running water rinsing alone was always more than 98%. To evaluate the contaminant level introduced to the lenses by the running water, 24 sterile lenses were also rinsed with running water. Our results indicated that these lenses were virtually not contaminated with running water rinsing. However, when 30 sterile lenses were handled by 15 soft contact lens wearers in the same manner as they would prior to inserting the lenses in their eyes, thousands of contaminants were recovered per lens in average. Furthermore, when lenses containing different water levels were rinsed in water, followed by soaking in a sterile isotonic saline solution, none of the lenses were adversely affected physically by the water rinse. From the results of this study, we believe that it is safe to use running water to rinse soft contact lenses in conjunction with a safe holding device and a proper disinfecting regimen

Individual differences in visual word recognition: Insights from the English Lexicon Project

10.1037/a0024177Journal of Experimental Psychology: Human Perception and Performance38153-79JPHP