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刻意创新     
我们大多数人都认同创新是成长的关键途径。问题是如何创新?许多企业依靠突发机遇。也就是说,他们指望某个人提出产品或服务方面的点子,然后从中获利。然而有些时候,企业必须发掘比以往更多的创意,并先于竞争对手将创意化为切实可行的产品与服务。此时,企业便不能再依靠机缘巧合了。我们需要可持续、可重复的创新方法。  相似文献   
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The 2014 release of a new set of purchasing power parity (PPP) conversion factors (PPPs) for 2011 has prompted a revision of the World Bank’s international poverty line. In revising the line, we have sought to minimize changes to the real purchasing power of the earlier $1.25 line (in 2005 PPPs), so as to preserve the integrity of the goalposts for international targets such as the Sustainable Development Goals (SDGs) and the World Bank’s twin goals – which were set with respect to that line. In particular, the new line was obtained by inflating the same fifteen national poverty lines – originally used by Ravallion et al. (World Bank Econ. Rev. 23(2): 163–184 2009) to construct the $1.25 line – to 2011 prices in local currency units, and then converting them to US dollars using 2011 PPP conversion factors. With a small approximation, this procedure yields a new international poverty line of $1.90 per person per day. In combination with other changes described in the paper, this revision leads to relatively small changes in global poverty incidence for 2011: from 14.5 % using the old method to 14.1 % using the new method. In 2012, the new reference year for the global count, we find 12.7 % of the world’s population, or 897 million people, are living in extreme poverty. There are changes in the regional composition of poverty, but they are also relatively small. This paper documents methodological decisions taken in the process of updating both the poverty line and the consumption and income distributions at the country level, including issues of inter-temporal and spatial price adjustments. It also describes various caveats and limitations of the approach taken.  相似文献   
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The cost of an uncontrolled incursion of invasive alien species (IAS) arising from undetected entry through ports can be substantial, and knowledge of port‐specific risks is needed to help allocate limited surveillance resources. Quantifying the establishment likelihood of such an incursion requires quantifying the ability of a species to enter, establish, and spread. Estimation of the approach rate of IAS into ports provides a measure of likelihood of entry. Data on the approach rate of IAS are typically sparse, and the combinations of risk factors relating to country of origin and port of arrival diverse. This presents challenges to making formal statistical inference on establishment likelihood. Here we demonstrate how these challenges can be overcome with judicious use of mixed‐effects models when estimating the incursion likelihood into Australia of the European (Apis mellifera) and Asian (A. cerana) honeybees, along with the invasive parasites of biosecurity concern they host (e.g., Varroa destructor). Our results demonstrate how skewed the establishment likelihood is, with one‐tenth of the ports accounting for 80% or more of the likelihood for both species. These results have been utilized by biosecurity agencies in the allocation of resources to the surveillance of maritime ports.  相似文献   
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Though language manifests linearly, one word at a time, children must learn that words are embedded in constituents, which are in turn embedded in larger constituents. That is, they must learn that syntax is hierarchically structured. Prosody—speech melody and rhythm—is likewise hierarchically organized, with smaller prosodic constituents embedded in larger ones. This paper presents results showing that 20‐month‐olds (= 40) can use modifier + clause prosody to learn constituents at multiple levels in a hierarchically structured artificial grammar, but that they fail to learn from clause + modifier prosody. We consider several explanations for this asymmetry, and suggest that it may be due to the frequency of the two constructions in the input. Two parallel experiments with adults suggest that older learners may not be able to learn the prosodically marked constituents. Instead, adult responses are likely based on perceptually prominent boundary words.  相似文献   
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Population Research and Policy Review - The current study examines the association between social context and the formation of same-sex coresidential unions, with a particular focus on sexual...  相似文献   
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When immigrants enter the US they typically access a marriage market with a larger supply of educated spouses compared to the marriage market in their home countries. Absent any selectivity bias, this access should increase the likelihood that migrants ‘marry-up’ in terms of education. We combine survey data on British and German immigrants in the US with data on natives in Britain and Germany to estimate the causal effect of migration on educational mobility through cross-national marriage. To control for selective mating, we instrument educational attainment using government spending on education in the years each person was of school-age. To control for selective migration, we instrument the migration decision using inflows of immigrants to the US during puberty and early adulthood. We find strong selectivity effects that work against the positive prospects of the US marriage market. All migrants give up spousal education in exchange for US entry and assimilation. Migrant men also give up spousal education because they cannot compete with native men as bread-earners. Migrant women have some advantage in the US marriage market, as they can compete with native women in home production.  相似文献   
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This article deconstructs the “illegal–legal” binary that characterizes much immigration scholarship. Using in‐depth interviews with 42 1.5‐generation Brazilian immigrants in young adulthood, I find that respondents discuss a distinct hierarchy with four categories of legal membership—undocumented, liminal legality, lawful permanent resident (LPR), and citizen—that affect their daily lives and incorporation. Liminally legal and LPR statuses in particular challenge this illegal–legal dichotomy. Liminal legality is an “in‐between” status in which immigrants possess social security numbers and work permits but have no guarantee of eventual citizenship. Without opportunities to regularize their status, both undocumented and liminally legal young adults face increased vulnerabilities to poverty and social exclusion. Liminally legal youth, however, are in better positions than their undocumented peers during early adulthood because of state‐delimited rights associated with their legal status.  相似文献   
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