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211.
In this paper, we assume that the duration of a process has two different intrinsic components or phases which are independent. The first is the time it takes for a trade to be initiated in the market (for example, the time during which agents obtain knowledge about the market in which they are operating and accumulate information, which is coherent with Brownian motion) and the second is the subsequent time required for the trade to develop into a complete duration. Of course, if the first time is zero then the trade is initiated immediately and no initial knowledge is required. If we assume a specific compound Bernoulli distribution for the first time and an inverse Gaussian distribution for the second, the resulting convolution model has a mixture of an inverse Gaussian distribution with its reciprocal, which allows us to specify and test the unobserved heterogeneity in the autoregressive conditional duration (ACD) model.

Our proposals make it possible not only to capture various density shapes of the durations but also easily to accommodate the behaviour of the tail of the distribution and the non monotonic hazard function. The proposed model is easy to fit and characterizes the behaviour of the conditional durations reasonably well in terms of statistical criteria based on point and density forecasts.  相似文献   

212.
213.
Psychological capital (PsyCap) has been a topic of increasing interest in the last decade. However, there is a lack of validated instruments in Spanish to map PsyCap and its consequences for individuals’ well-being. Consequently, the goal of this study is to adapt the 12-item short version of the Psychological Capital Questionnaire (PCQ-12) to the Spanish context by analysing its internal consistency and reliability, factor solution and external validity. Results indicated that the PCQ-12 exhibited good Cronbach’s alpha (.87) and omega coefficient (.93) values in a sample from a vehicle inspection company (n = 798). As expected, results also revealed that a second-order factor structure provided the best fit. Moreover, PsyCap is associated with increased job engagement (β = .579; R2adjusted = .333), decreased job burnout (β = ?.409; R2adjusted = .166), and lower psychological distress (β = ?.349; R2adjusted = .121) (all < .01), which provided additional support for using the PCQ-12 in the Spanish context. Implications for theory and practice are discussed.  相似文献   
214.
In order to ensure sustainable development, aid donors need to improve the environmental effectiveness of their whole activity. This improvement seems to be influenced by their interactions with environmental NGOs (ENGOs). Faced with a diversity of interactions between these two kinds of actors, a strategic typology is proposed here to describe this multiplicity and, by doing so, to consider their environmental impact. Four relational postures have been identified: (i) external advocacy and (ii) the cooperation–criticism focus on the antagonistic link that exists between environment and development; (iii) environmental collaboration, and (iv) service provision, which focus on synergies that can exist between environment protection and development issues. Win–win solutions need to be continuously sought and enhanced. However, ENGOs and donors are called to recognize the necessity of maintaining a critical position in actors’ interactions vis-à-vis the implementation of development activities that are detrimental for the environment.  相似文献   
215.
Non-governmental organizations (NGOs) in sub-Saharan Africa (SSA) experience financial challenges that hinder efforts to promote social change and development. Revenue diversification is one adaptive response to these challenges, yet there is a lack of evidence concerning the relationship between revenue diversification and financial vulnerability among NGOs in SSA. Using data from an online survey of NGOs (N = 170), we hypothesized that a greater number of revenue sources is associated with lower probability of financial vulnerability, while a greater level of dependence on international funding is associated with higher probability of financial vulnerability. Results from probit regression models controlling for organizational characteristics indicated partial support for hypotheses. Having four or more types of revenue was associated with 87% lower probability of financial vulnerability compared to having one type of revenue (p < 0.001). Also, NGOs with up to half of their budgets covered by international sources had 17% lower probability of financial vulnerability compared to NGOs with no international funding (p < 0.05). Implications for future research to further explore these relationships are discussed.  相似文献   
216.
The goal of this study is to analyse the differences in attitudes towards habitual modes of transportation among users of public and private transportation. The explanatory capacity of attitudes when determining the mode choice, along with the structural and sociodemographic factors, are also verified. The study was performed in three Spanish cities with 742 participants. The results revealed that cars are better rated than public modes of transportation in the attributes associated with immediate advantages (i.e., speed and availability) and convenience. Subways are highly rated in both immediate and deferred advantages (environment, safety, cost and health). Buses are the mode rated the lowest of the three. Using logistic regression, it was verified that the variance explained by a model that includes attitudes (R2 = .639) is higher than the variance explained by a model based solely on variables related to infrastructures (R2 = .489). The discussion of these results includes proposals aimed at decreasing car use.  相似文献   
217.
The aim of this article is to examine senior women's involvement experience in Quebec, Canada. Study results are based on a qualitative methodology, and shed light on family history and continuity in the involvement trajectory, diversity in terms of group type and involvement practices, and gender differences in involvement. The meaning that older women attribute to their involvement is also addressed, including attitudes toward feminism. The discussion highlights the extent to which older women's involvement has been marked by their life trajectories, above and beyond their age. In sum, their involvement in the private and public spheres is quite impressive.  相似文献   
218.
Measuring access to water in the Sustainable Development Goals era involves taking into account the human rights framework. Therefore, its content should be considered to conceptualize the level of service through adequate indicators and to follow-up inequities reduction at global, national and local level. This research develops and tests a methodology to measure intra-community disparities based on human right to water normative criteria through a stratified sampling, splitting households served by community based organizations and those self-provided. This approach implies considering much reduced populations, thus special care needs to be taken with sample sizes and uncertainty of estimators. The proposed methodology is practical to locate and accurately characterize minority sectors within rural communities and allows moving beyond central-tendency estimators. It implies higher costs for field data collection than traditional approaches, but this can be assumed given the relevance of the approach from a human rights perspective, which calls for adequate tools for equity-oriented policy making at local level. The research point out how results might be used to shape decision-making processes.  相似文献   
219.
We investigated the association between number of offspring and later-life mortality of Finnish men and women born 1938–50, and whether the association was explained by living conditions in own childhood and adulthood, chronic conditions, fertility timing, and unobserved characteristics common to siblings. We used a longitudinal 1950 census sample to estimate mortality at ages 50–72. Relative to parents of two children, all-cause mortality is highest among childless men and women, and elevated among those with one child, independently of observed confounders. Fixed-effect models, which control for unobserved characteristics shared by siblings, clearly support these findings among men. Cardiovascular mortality is higher among men with no, one, or at least four children than among those with two. Living conditions in adulthood contribute to the association between the number of children and mortality to a greater extent than childhood background, and chronic conditions contribute to the excess mortality of the childless.  相似文献   
220.
This evaluation examined school and parent reports of the national student achievement testing system (SIMCE) in Chile regarding three dimensions: access, comprehension, and use. We conducted phone surveys with a representative sample of directors (N = 375), teachers (N = 1145) and parents (N = 625), and we collected more in-depth data through interviews and focus groups in 16 of these schools. The results indicate that access to the reports is not an obstacle to use for school actors, but it is for parents. While summative ratings of the reports in terms of their clarity and utility were generally very positive, the actual recall and interpretation of even basic information (assessed through case scenarios) was incorrect for a majority of teachers and parents, and reported uses of the information were both intended and unintended in nature. We also found some statistically significant differences regarding comprehension and use among subgroups of our sample. Our findings are especially relevant given the expectations attached to the use of the reports for school improvement on the one hand, and parents’ behavior as critical consumers of education on the other hand.  相似文献   
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