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141.
142.
The author used a new longitudinal data set, the How Couples Meet and Stay Together surveys (N = 3,009), to generate the first nationally representative comparison of same‐sex couple stability and heterosexual couple stability in the United States. He measured the association between marriage (by several definitions of marriage) and couple longevity for same‐sex couples in the United States. Reports of same‐sex relationship instability in the past were due in part to the low rate of marriages among same‐sex couples. After controlling for marriage and marriage‐like commitments, the break‐up rate for same‐sex couples was comparable to (and not statistically distinguishable from) the break‐up rate for heterosexual couples. The results revealed that same‐sex couples who had a marriage‐like commitment had stable unions regardless of government recognition. A variety of predictors of relationship dissolution for heterosexual and for same‐sex couples are explored.  相似文献   
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144.
In this paper we compare several types of economic dependency ratios for a selection of European countries. These dependency ratios take into account not only the demographic structure of the population, but also the differences in age-specific economic behaviour such as labour market activity, income and consumption as well as age-specific public transfers. In selected simulations where we combine patterns of age-specific economic behaviour and transfers with population projections, we show that in all countries population ageing would lead to a pronounced increase in dependency ratios if present age-specific patterns were not to change. Our analysis of cross-country differences in economic dependency demonstrates that these differences are driven by both differences in age-specific economic behaviour and in the age composition of the populations. The choice of which dependency ratio to use in a specific policy context is determined by the nature of the question to be answered. The comparison of our various dependency ratios across countries gives insights into which strategies might be effective in mitigating the expected increase in economic dependency due to demographic change.  相似文献   
145.
The application of the exponential model is extended by the inclusion of new nonhuman primate (NHP), rabbit, and guinea pig dose‐lethality data for inhalation anthrax. Because deposition is a critical step in the initiation of inhalation anthrax, inhaled doses may not provide the most accurate cross‐species comparison. For this reason, species‐specific deposition factors were derived to translate inhaled dose to deposited dose. Four NHP, three rabbit, and two guinea pig data sets were utilized. Results from species‐specific pooling analysis suggested all four NHP data sets could be pooled into a single NHP data set, which was also true for the rabbit and guinea pig data sets. The three species‐specific pooled data sets could not be combined into a single generic mammalian data set. For inhaled dose, NHPs were the most sensitive (relative lowest LD50) species and rabbits the least. Improved inhaled LD50s proposed for use in risk assessment are 50,600, 102,600, and 70,800 inhaled spores for NHP, rabbit, and guinea pig, respectively. Lung deposition factors were estimated for each species using published deposition data from Bacillus spore exposures, particle deposition studies, and computer modeling. Deposition was estimated at 22%, 9%, and 30% of the inhaled dose for NHP, rabbit, and guinea pig, respectively. When the inhaled dose was adjusted to reflect deposited dose, the rabbit animal model appears the most sensitive with the guinea pig the least sensitive species.  相似文献   
146.
We propose a methodology, called defender–attacker decision tree analysis, to evaluate defensive actions against terrorist attacks in a dynamic and hostile environment. Like most game‐theoretic formulations of this problem, we assume that the defenders act rationally by maximizing their expected utility or minimizing their expected costs. However, we do not assume that attackers maximize their expected utilities. Instead, we encode the defender's limited knowledge about the attacker's motivations and capabilities as a conditional probability distribution over the attacker's decisions. We apply this methodology to the problem of defending against possible terrorist attacks on commercial airplanes, using one of three weapons: infrared‐guided MANPADS (man‐portable air defense systems), laser‐guided MANPADS, or visually targeted RPGs (rocket propelled grenades). We also evaluate three countermeasures against these weapons: DIRCMs (directional infrared countermeasures), perimeter control around the airport, and hardening airplanes. The model includes deterrence effects, the effectiveness of the countermeasures, and the substitution of weapons and targets once a specific countermeasure is selected. It also includes a second stage of defensive decisions after an attack occurs. Key findings are: (1) due to the high cost of the countermeasures, not implementing countermeasures is the preferred defensive alternative for a large range of parameters; (2) if the probability of an attack and the associated consequences are large, a combination of DIRCMs and ground perimeter control are preferred over any single countermeasure.  相似文献   
147.
The internet and other digital networks in the U.S. (and beyond) remain essentially an upgrade of the national telephone network built by AT&T over the first half of the twentieth century, and digital payment remains tethered to telephony at the level of infrastructure. Telephone history also continues to inform digital payment at the level of interface. Debit card readers feature a keypad nearly identical to those introduced (also by AT&T) to the dialling public a half-century ago on touch-tone telephones. In this essay I highlight the development of the touch-tone keypad as a transformative payment technology. There have been three great leaps forward in the history of telephone interface: the dial, the keypad and the touch screen. Each corresponds to a period of technological transformation in the telephone industry and society more broadly: the rotary dial and automation, touch-tone keypads and digitization, and touch screens and computerization. The successful careers of the dial and the keypad, especially when read in tandem, suggest that touch screens will alter the everyday economics of retail payment even more radically than its predecessors. I also describe a broader trajectory of digital naturalization, whereby telephone numbers have proliferated into a personal identification number, passwords and a plethora of personalized information. Payments increasingly circulate today as subsets of personal information within the vast sea of big data. Payment apps are demonstrating a capacity to reorganize retail transactions on a scale as vast as any technology since the cash register. The history of retail payment finds the point of sale heading from the till into shoppers’ pockets. As a result, consumers are increasingly shouldering the costs of purchasing, maintaining, upgrading and securing the technology used for everyday transactions.  相似文献   
148.
In this article, I explore the intricate relationship between regulation and contingency in processes of urban economic organisation by focusing on the workings of a central bus station in Accra, Ghana. After introducing the position of the station in Ghana’s urban economy and transport infrastructure, I set out its internal regulative arrangements in relation to larger socio-economic and political constellations the practices of the station workers are contingent upon. Next, I turn the analysis around and describe the ways in which people accommodate themselves within, exploit and thereby co-produce emergent contingencies. The focus on the station, I suggest, offers a window into the complex constituents of niche economic practices that prevail in many spheres of African cities and allows a nuanced reflection on the incongruous and undetermined dynamics of everyday urban ‘becomings.’  相似文献   
149.
Urban growth is a major factor of global environmental change and has important impacts on biodiversity, such as changes in species composition and biotic homogenization. Most previous studies have focused on effects of urban area as a general measure of urbanization, and on few or single taxa. Here, we analyzed the impacts of the different components of urban sprawl (i.e., scattered and widespread urban growth) on species richness of a variety of taxonomic groups covering mosses, vascular plants, gastropods, butterflies, and birds at the habitat and landscape scales. Besides urban area, we considered the average age, imperviousness, and dispersion degree of urban area, along with human population density, to disentangle the effects of the different components of urban sprawl on biodiversity. The study was carried out in the Swiss Plateau that has undergone substantial urban sprawl in recent decades.Vascular plants and birds showed the strongest responses to urban sprawl, especially at the landscape scale, with non-native and ruderal plants proliferating and common generalist birds increasing at the expense of specialist birds as urban sprawl grew. Overall, urban area had the greatest contribution on such impacts, but additional effects of urban dispersion (i.e., increase of non-native plants) and human population density (i.e., increases of ruderal plants and common generalist birds) were found. Our findings support the hypothesis that negative impacts of urban sprawl on biodiversity can be reduced by compacting urban growth while still avoiding the formation of very densely populated areas.  相似文献   
150.
The six recommendations made by the Guidelines for Assessment and Instruction in Statistics Education (GAISE) committee were first communicated in 2005 and more formally in 2010. In this article, 25 introductory statistics textbooks are examined to assess how well these textbooks have incorporated the three GAISE recommendations most relevant to implementation in textbooks (statistical literacy and thinking; use of real data; stress concepts over procedures). The implementation of another recommendation (using technology) is described but not assessed. In general, most textbooks appear to be adopting the GAISE recommendations reasonably well in both exposition and exercises. The textbooks are particularly adept at using real data, using real data well, and promoting statistical literacy. Textbooks are less adept—but still rated reasonably well, in general—at explaining concepts over procedures and promoting statistical thinking. In contrast, few textbooks have easy-usable glossaries of statistical terms to assist with understanding of statistical language and literacy development. Supplementary materials for this article are available online.  相似文献   
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