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21.
This paper concerns the forecasting of seasonal intraday time series that exhibit repeating intraweek and intraday cycles. A recently proposed exponential smoothing method involves smoothing a different intraday cycle for each distinct type of day of the week. Similar days are allocated identical intraday cycles. A limitation is that the method allows only whole days to be treated as identical. We introduce a new exponential smoothing formulation that allows parts of different days of the week to be treated as identical. The result is a method that involves the smoothing and initialisation of fewer terms. We evaluate forecasting up to a day ahead using two empirical studies. For electricity load data, the new method compares well with a range of alternatives. The second study involves a series of arrivals at a call centre that is open for a shorter duration at the weekends than on weekdays. Among the variety of methods considered, the new method is the only one that can model in a satisfactory way in this situation, where the number of periods on each day of the week is not the same.  相似文献   
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Objective: To understand how the Greek system uniquely influences smoking attitudes, beliefs, and behaviors among college students who belong to a social sorority or fraternity. Participants: Active members of sororities (n = 16) and fraternities (n = 17) were interviewed between February 2013 and October 2015. Methods: In-depth interviews were conducted examining the social influences of the Greek system on member smoking. Transcribed interviews were coded and analyzed for themes. Results: Sorority and fraternity members experienced different social influences on smoking. Sorority stigmatization of smoking outside bars or parties caused sorority members to hide their smoking. Fraternity members had no social penalties for smoking and allowed smoking at the fraternity house. Fraternity members influenced both fraternity members and sorority members to smoke by sharing cigarettes and smoking at parties. Conclusions: Sororities and fraternities have created social environments that both promote smoking and stigmatize it, presenting unique challenges in college student smoking prevention and cessation efforts.  相似文献   
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Research on polyamorous relationships has increased substantially over the past decade. This work has documented how polyamory is practiced and why individuals might pursue such arrangements. However, there is a lack of a systematic investigation of who is in polyamorous relationships and how they might differ from individuals in monogamous relationships. The present study is one of the first to address this by comparing the demographic backgrounds of individuals in polyamorous (N = 2,428) and monogamous (= 539) relationships in the United States. Compared to participants in monogamous relationships, those in polyamorous relationships were more likely to report minority sexual identities. Despite similar age distributions, individuals in polyamorous relationships were more likely to report being in a civil union, being divorced, and earning less than $40,000 per year compared to individuals in monogamous relationships. People in polyamorous relationships were also more likely to select “other” options for most demographic characteristics, suggesting that they tend to choose less traditional response options in general. The current research highlights several demographic differences that need to be considered and potentially controlled for in future comparisons of polyamorous and monogamous relationships.  相似文献   
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Popular commentaries lament that reforms to the financing of Higher Education (HE) in the UK will operate as a significant deterrent to HE participation amongst students from less advantaged backgrounds. This view of debt as a deterrent is powerful and exists not only at a societal level, but also, as we show, is present in schools. Our data reveal, however, that these ‘debt commentaries’ play out very differently across schools according to the nature of their catchment and the sorts of views staff hold about pupils in relation to their fear of debt. Furthermore, students’ views on debt largely contradict these popular ‘debt-as-deterrent’ narratives and instead are often characterised by acceptance, ambivalence and at times positive orientations towards the prospect of debt. These findings vividly illuminate both the regional and institutional specificity of staff and student decision making in relation to ‘debt’, hence they have substantial implications for HE funding policy specifically and debates about widening participation in HE more generally, where ensuring greater equity in the scope of choices young people have when it comes to choosing a university is a pressing concern.  相似文献   
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Given a noisy time series (or signal), one may wish to remove the noise from the observed series. Assuming that the noise-free series lies in some low-dimensional subspace of rank r, a common approach is to embed the noisy time series into a Hankel trajectory matrix. The singular value decomposition is then used to deconstruct the Hankel matrix into a sum of rank-one components. We wish to demonstrate that there may be some potential in using difference-based methods of the observed series in order to provide guidance regarding the separation of the noise from the signal, and to estimate the rank of the low-dimensional subspace in which the true signal is assumed to lie.  相似文献   
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This study considers key value differences between leaders of two types of social ventures: for-profit social benefit corporations and nonprofit organizations. The research question asks to what degree the value sets of leaders of benefit corporations are congruent with those of similarly situated individuals in nonprofit organizations. The results show the values of leaders working in benefit corporations and nonprofit organizations are in many ways aligned, but there are notable statistical differences. A sectoral association of values is also present with employees in both types of organization, especially when the previous work experience of employees is considered.  相似文献   
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This article compares mothers’ experience of having children with more than one partner in two liberal welfare regimes (the United States and Australia) and two social democratic regimes (Sweden and Norway). We use survey-based union and birth histories in Australia and the United States and data from national population registers in Norway and Sweden to estimate the likelihood of experiencing childbearing across partnerships at any point in the childbearing career. We find that births with new partners constitute a substantial proportion of all births in each country we study. Despite quite different arrangements for social welfare, the determinants of childbearing across partnerships are very similar. Women who had their first birth at a very young age or who are less well-educated are most likely to have children with different partners. The educational gradient in childbearing across partnerships is also consistently negative across countries, particularly in contrast to educational gradients in childbearing with the same partner. The risk of childbearing across partnerships increased dramatically in all countries from the 1980s to the 2000s, and educational differences also increased, again, in both liberal and social democratic welfare regimes.  相似文献   
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