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121.
This experiment investigated the effect of peer discouragement on adolescent risk taking. Overall, 269 Dutch adolescents aged 11–15 years completed a risk taking computer task in the presence of an e‐confederate who demonstrated very little risk taking (passive peer discouragement) and/or sent risk‐discouraging messages to participants (active peer discouragement). The results showed that, compared to a situation with no peer discouragement, adolescents took significantly less risk only when they encountered a combination of active and passive peer discouragement; hence, when peers practiced what they preached. No gender differences were found in the effect of passive and active peer discouragement on risk taking. The results showed that digital peer messages play a promising role in diminishing adolescent risk taking.  相似文献   
122.
Urban afforestation improves life quality in urban centers providing social and environmental benefits. Understanding growth of urban trees exposed to air pollution will support planning, managing and expanding urban areas. This approach intends to determine growth patterns of urban trees to support future urban planning. Non-destructive samples were collected from trees of Araucaria angustifolia (Bertol.) Kuntze in Araucaria city, Parana State, Brazil. Growth rings were related to pollutant concentrations and meteorological series. Growth reduction was observed except in the border areas of the city. Trees established during or after the period of industrialization incentives were most affected by air pollution, indicating that immature plants are more vulnerable. Sulphur dioxide and nitric oxide significantly affected growth of smaller trees. Those greater than 60 cm dbh did not demonstrate significant correlation with any identified pollutant. As the trees established before accentuated urbanization were less affected by air pollution, it is reinforced the importance of preserving remaining urban trees. We suggest that planning urban afforestation should precede industries placing. When urban planning is impossible, new planted trees should not be expected to grow as in free pollution areas, but they will still present satisfactory diameter increment, contributing to improve local urban environment.  相似文献   
123.
In a recent article from the Annals of Applied Statistics, Cox discussed the main phases of applied statistical research ranging from clarifying study objectives to final data analysis and interpreting results. As an incidental remark to these main phases, we advocate that beyond cleaning and preprocessing the data, it is a good practice to audit the data to determine if they can be trusted at all. A case study based on Ghanaian Official Fishery Statistics is used to illustrate this need, with Benford's law being the tool used to carrying out the data audit. Supplementary materials for this article are available online.  相似文献   
124.
ABSTRACT

In 2013, after nearly two decades of operating in a distributed legacy Integrated Library System (ILS) environment on local servers, the Orbis Cascade Alliance, a consortium of public and private academic libraries in Washington, Oregon, and Idaho, began a two-year-long process to migrate its 37 members to a shared implementation of Ex Libris's cloud-based Alma library management system (LMS) and Primo discovery interface. Although much has been written on electronic resource management (ERM) functionality at an institution level, little has been written on serials and ERM functionality and workflows within a shared consortial environment. This article discusses the challenges and opportunities of implementing a consortial-based LMS, with particular emphasis on serials and ERM functionality. Key migration issues related to serials control, acquisitions, licensing, administration, cataloging, statistics, and interoperability are examined at the institutional and large-scale networked levels. Benefits and limitations of using a shared consortial cloud-based LMS are explored, and the overall capabilities of the Alma LMS for electronic resource management are reviewed.  相似文献   
125.
High-content automated imaging platforms allow the multiplexing of several targets simultaneously to generate multi-parametric single-cell data sets over extended periods of time. Typically, standard simple measures such as mean value of all cells at every time point are calculated to summarize the temporal process, resulting in loss of time dynamics of the single cells. Multiple experiments are performed but observation time points are not necessarily identical, leading to difficulties when integrating summary measures from different experiments. We used functional data analysis to analyze continuous curve data, where the temporal process of a response variable for each single cell can be described using a smooth curve. This allows analyses to be performed on continuous functions, rather than on original discrete data points. Functional regression models were applied to determine common temporal characteristics of a set of single cell curves and random effects were employed in the models to explain variation between experiments. The aim of the multiplexing approach is to simultaneously analyze the effect of a large number of compounds in comparison to control to discriminate between their mode of action. Functional principal component analysis based on T-statistic curves for pairwise comparison to control was used to study time-dependent compound effects.  相似文献   
126.
We derive an empirical poverty index containing most of those proposed in the literature. Then, we study its asymptotic behavior by using empirical processes theory. From the results obtained, we derive a Wald-type test for comparing a vector of theoretical poverty indices to a vector of reference indices. We study the test statistic under the null hypothesis of equality, fixed alternatives, and a sequence of local alternatives. A simulation experiment conducted shows that our test performs well for exponential and Pareto data.  相似文献   
127.
The randomized response technique (RRT) is an important tool, commonly used to avoid biased answers in survey on sensitive issues by preserving the respondents’ privacy. In this paper, we introduce a data collection method for survey on sensitive issues combining both the unrelated-question RRT and the direct question design. The direct questioning method is utilized to obtain responses to a non sensitive question that is related to the innocuous question from the unrelated-question RRT. These responses serve as additional information that can be used to improve the estimation of the prevalence of the sensitive behavior. Furthermore, we propose two new methods for the estimation of the proportion of respondents possessing the sensitive attribute under a missing data setup. More specifically, we develop the weighted estimator and the weighted conditional likelihood estimator. The performances of our estimators are studied numerically and compared with that of an existing one. Both proposed estimators are more efficient than the Greenberg's estimator. We illustrate our methods using real data from a survey study on illegal use of cable TV service in Taiwan.  相似文献   
128.
This paper describes the population of children in care in New South Wales, Australia, who were adopted by their foster families (N?=?372) from 2003 to 2014. Data pertaining to 370 of these adoptees were available and obtained from administrative records accompanying adoption applications. Most of these children had been placed with their subsequent adoptive family during infancy. However, adoption orders occurred much later in their lives. According to the available information at the time of adoption, these children did not suffer the high levels of mental health problems typically identified in populations of children in foster care. Though the data do not include follow-up to determine if the contact agreed upon at the time of adoption orders translated into practice, the most frequently postadoption arrangement recorded was face-to-face contact, four times a year with mother and siblings. The high levels of openness and face-to-face contact in Australian adoptions from care are a significant point of difference with other adoption models, and presents a need for research in the area.

IMPLICATIONS
  • Following the change of legislation in New South Wales, Australia, that prioritises open adoption over foster care, social workers in the field of child protection are well placed to assist in this process.

  • Social workers can assess children entering care to identify those who will benefit from adoption in a timely manner; undertake casework and administrative aspects of the adoption process; work closely with the child, and birth and adoptive families by delivering pre- and post-adoption supports; and conduct longitudinal research on the outcomes for children adopted from care.

  相似文献   
129.
This study examines immigrants' identification with the host country. We use survey data of more than 1,700 Turkish and Moroccan immigrants and more than 2,200 natives in the Netherlands. We answer four main questions in this study. First, do immigrants have lower national identification than natives? Second, does the level of national identification differ between immigrant groups? Third, do economic and social integration similarly affect national identification among immigrants and natives? And fourth, what are important additional determinants of national identification among immigrants? The results show that, compared to Dutch natives, Turkish but not Moroccan immigrants have lower national identification. Being employed and socially integrated is associated with higher national identification among immigrants as well as natives, but only among immigrants is higher occupational status associated with higher national identification. For immigrants, Dutch language proficiency, perceived discrimination, and contact with natives proved to be important conditions for national identification.  相似文献   
130.
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