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21.

Biological invasions represent today one of the main cause of the global biodiversity crisis, particularly in urban and suburban areas. Research on this topic have traditionally focused on ecological impacts, with poor regards to the social components. The ring-necked parakeet Psittacula krameri is one of the most successful invaders and it is widely appreciated by the general public, being introduced through the pet trade. In this work we assessed whether long-term introduction, total population size and number of loud flight-calls affected social perception of this species in three populations from Italian cities. We used a visual survey (N?=?414 questionnaires), which has been proven to be successful for testing attitudes on ring-necked parakeets. Tolerance towards this invasive species declined sharply with increasing number of loud calls by this species, thus providing support to the hypothesis of involvement of the ring-necked parakeet in noise pollution. Conversely, total population size and years since the first local introduction were not found out to be important variable determining social attitudes. Awareness on invasive species impacts is mostly obtained only when invasive populations are already affecting native biodiversity and human wellness, thus when management becomes challenging. Thus, at early invasion stages, intervention towards invasive species, particularly if charismatic, are often hampered by social public and animal right movements, especially in urban ecosystems. Educational campaigns on ecological and social impact by invasive alien species in urban ecosystems are therefore strongly recommended to implement effective management actions.

  相似文献   
22.
Previous studies have suggested that the reunion episode of the still‐face procedure has the potential to reveal the regulatory resources of the mother–infant dyad that appear to be predictive of future adaptation. Nevertheless, differences across dyads with respect to these resources have received little attention, as also have the factors that are responsible for such differences. This study addresses this gap in the literature by testing whether the dyad reunion patterns can be predicted by the mothers' sensitivity assessed 3 months earlier, and by the contingent degree of the matched states in the play episode. Three dyadic patterns were identified through cluster analysis, which were characterized by playful, neutrally matched, and disrupted interactions. Multinomial logistic regression shows that the mothers' sensitivity predicts membership to the playful group, and the matched states in the play episode predict membership to the neutrally matched and disrupted groups. These findings show that the vulnerability to disrupt an ongoing interaction after a temporary perturbation is seen for only some dyads; moreover, they support the view of early regulatory development as a multidetermined achievement. Overall, these findings have important theoretical implications related to the identification of early regulatory difficulties as precursors of later developmental outcomes.  相似文献   
23.
Evidence from several countries has shown the over‐representation of racial/ethnic minority groups in child protection services (CPS). The objective of the present study was to explore whether racial/ethnic and socio‐economic biases influence Spanish CPS caseworkers' judgements of the severity of child maltreatment. Moreover, the study attempted to explore the influence on these judgements of the use of structured instruments and professional experience. Two case vignettes of child maltreatment were presented to 405 CPS caseworkers and 169 students of social work and psychology. Family ethnic origin and income were manipulated in the vignettes. The findings showed no statistical evidence of biases related to family ethnic origin or socio‐economic status (SES) in Spanish CPS caseworkers' judgements of maltreatment severity. Biases related to family SES were found for students for the vignettes of physical abuse. CPS caseworkers and students who did not use a structured instrument to assess maltreatment severity tended to underestimate the severity for the vignettes of parental incapacity to control child/adolescent behaviour and to overestimate it for the vignettes of physical abuse. CPS caseworkers who used a structured instrument showed higher percentages of accuracy and inter‐rater agreement, supporting the relevance of structured tools in reducing potential caseworkers' biases.  相似文献   
24.
Air pollution has been linked to an increased risk of several respiratory diseases in children, especially respiratory tract infections. The present study aims to evaluate the association between pediatric emergency department (PED) presentations for bronchiolitis and air pollution. PED presentations due to bronchiolitis in children aged less than 1 year were retrospectively collected from 2007 to 2018 in Padova, Italy, together with daily environmental data. A conditional logistic regression based on a time-stratified case-crossover design was performed to evaluate the association between PED presentations and exposure to NO2, PM2.5, and PM10. Models were adjusted for temperature, relative humidity, atmospheric pressure, and public holidays. Delayed effects in time were evaluated using distributed lag non-linear models. Odds ratio for lagged exposure from 0 to 14 days were obtained. Overall, 2251 children presented to the PED for bronchiolitis. Infants’ exposure to higher concentrations of PM10 and PM2.5 in the 5 days before the presentation to the PED increased the risk of accessing the PED by more than 10%, whereas high concentrations of NO2 between 2 and 12 days before the PED presentation were associated with an increased risk of up to 30%. The association between pollutants and infants who required hospitalization was even greater. A cumulative effect of NO2 among the 2 weeks preceding the presentation was also observed. In summary, PM and NO2 concentrations are associated with PED presentations and hospitalizations for bronchiolitis. Exposure of infants to air pollution could damage the respiratory tract mucosa, facilitating viral infections and exacerbating symptoms.  相似文献   
25.
A pivotal characteristic of credit defaults that is ignored by most credit scoring models is the rarity of the event. The most widely used model to estimate the probability of default is the logistic regression model. Since the dependent variable represents a rare event, the logistic regression model shows relevant drawbacks, for example, underestimation of the default probability, which could be very risky for banks. In order to overcome these drawbacks, we propose the generalized extreme value regression model. In particular, in a generalized linear model (GLM) with the binary-dependent variable we suggest the quantile function of the GEV distribution as link function, so our attention is focused on the tail of the response curve for values close to one. The estimation procedure used is the maximum-likelihood method. This model accommodates skewness and it presents a generalisation of GLMs with complementary log–log link function. We analyse its performance by simulation studies. Finally, we apply the proposed model to empirical data on Italian small and medium enterprises.  相似文献   
26.
Abstract

Differential item functioning (DIF) is present when something about the characteristics of a test taker interferes with the relationship between ability and item response. Non uniform DIF (NUDIF) exists when there is interaction between ability level and group membership. The aim of this study is to propose guidelines to evaluate the severity of NUDIF, taking into account the family of Rasch models. The severity of NUDIF is evaluated trying to quantify the overall biasing impact of the presence in the test of NUDIF items, on the estimated measure of the latent trait of interest.  相似文献   
27.
This article analyses aspirations and intentions to migrate based on Gallup World Poll for the period 2010–2015. We estimate individual‐level traits associated with aspirations and intentions to migrate across groups of countries in different regions and with different income levels. This paper brings together previous hypotheses regarding migration aspirations and tests them under several specifications, while keeping separate findings according to migration aspirations and intentions to appreciate differences between them. Being dissatisfied with one’s own standard of living is associated with a higher probability of desiring to move, while the relation with the actual preparation to migrate is less clear. Some individual traits remain significant across (almost) all specifications: being male, foreign‐born, highly educated, and having networks abroad are associated with higher probability of preparing for international migration. Aspects related to one’s economic situation are not consistently significant across specifications, signalling the importance of contextual analyses for these factors.  相似文献   
28.
Event counts are response variables with non-negative integer values representing the number of times that an event occurs within a fixed domain such as a time interval, a geographical area or a cell of a contingency table. Analysis of counts by Gaussian regression models ignores the discreteness, asymmetry and heteroscedasticity and is inefficient, providing unrealistic standard errors or possibly negative predictions of the expected number of events. The Poisson regression is the standard model for count data with underlying assumptions on the generating process which may be implausible in many applications. Statisticians have long recognized the limitation of imposing equidispersion under the Poisson regression model. A typical situation is when the conditional variance exceeds the conditional mean, in which case models allowing for overdispersion are routinely used. Less reported is the case of underdispersion with fewer modeling alternatives and assessments available in the literature. One of such alternatives, the Gamma-count model, is adopted here in the analysis of an agronomic experiment designed to investigate the effect of levels of defoliation on different phenological states upon the number of cotton bolls. Data set and code for analysis are available as online supplements. Results show improvements over the Poisson model and the semi-parametric quasi-Poisson model in capturing the observed variability in the data. Estimating rather than assuming the underlying variance process leads to important insights into the process.  相似文献   
29.
This study used the social cognitive theory of well‐being (SCTW; Lent, 2004 ) to examine the role of career decision self‐efficacy (CDSE), perceived educational barriers, and independent self‐construal on the life satisfaction of 176 Mexican American college women. A 3‐step hierarchical regression analysis indicated that independent self‐construal, CDSE, and fewer perceived educational barriers significantly predicted greater life satisfaction among Mexican American college women above and beyond the influence of socioeconomic status and generational status. These findings are consistent with SCTW and highlight the need for counselors and researchers to be aware of the role that self‐construal, CDSE, and perceived educational barriers can have on Mexican American women's life satisfaction. Implications for practice at the secondary‐school and university levels are discussed.  相似文献   
30.
This article deals with the estimation of parametric equivalence scales for Italian households with different demographic characteristics: composition, location and number of employed members in the household. Using a sample of 43,701 observations on monthly current expenditures from 1997 to 2004 we estimate a demand system for ten goods and we tackle the problem of corner solutions for some goods adopting the Two Step estimator proposed by Shonkweiler and Yen (Am J Agric Econ 81:972–982, 1999). The consumption behavior of households is also analyzed calculating compensated, uncompensated and expenditure elasticites for each commodity. By considering households that differ in composition (number of children), geographic location (four-different macro-areas of Italy), and number of employed adults, we allow for a range of useful comparisons.  相似文献   
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