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51.
This study is to determine the association between parenting style of mothers and the social competence of their adolescent daughters in effective communication, problem solving skills and use of basic social skills dimensions. The data were gathered for the mean age of 11–15 years on 737 Iranian adolescent girls in a cross sectional study design. The parenting style of mothers was based on their demand and responsiveness. These scales classified mothers into four parenting styles as follows: authoritative, authoritarian, permissive, or neglectful. The social competence was also categorized into effective relationship, problem solving skills, use of basic social skills dimensions. The mean scores of the adolescents’ social competence whose mothers had permissive and authoritative parenting style was higher than that for the two other groups for all the dimensions (p < 0.05). The results showed that with the expectation of controlling roles, the supportive role of mothers can be more effective in providing opportunities for social competence performance.  相似文献   
52.
Felicia Wu  Hasan Guclu 《Risk analysis》2013,33(12):2168-2178
In this study, we developed a social network model of the global trade of maize: one of the most important food, feed, and industrial crops worldwide, and critical to food security. We used this model to analyze patterns of maize trade among nations, and to determine where vulnerabilities in food security might arise if maize availability was decreased due to factors such as diversion to nonfood uses, climatic factors, or plant diseases. Using data on imports and exports from the U.N. Commodity Trade Statistics Database for each year from 2000 to 2009 inclusive, we summarized statistics on volumes of maize trade between pairs of nations for 217 nations. There is evidence of market segregation among clusters of nations; with three prominent clusters representing Europe, Brazil and Argentina, and the United States. The United States is by far the largest exporter of maize worldwide, whereas Japan and the Republic of Korea are the largest maize importers. In particular, the star‐shaped cluster of the network that represents U.S. maize trade to other nations indicates the potential for food security risks because of the lack of trade these other nations conduct with other maize exporters. If a scenario arose in which U.S. maize could not be exported in as large quantities, maize supplies in many nations could be jeopardized. We discuss this in the context of recent maize ethanol production and its attendant impacts on food prices elsewhere worldwide.  相似文献   
53.
Longitudinal count data with excessive zeros frequently occur in social, biological, medical, and health research. To model such data, zero-inflated Poisson (ZIP) models are commonly used, after separating zero and positive responses. As longitudinal count responses are likely to be serially correlated, such separation may destroy the underlying serial correlation structure. To overcome this problem recently observation- and parameter-driven modelling approaches have been proposed. In the observation-driven model, the response at a specific time point is modelled through the responses at previous time points after incorporating serial correlation. One limitation of the observation-driven model is that it fails to accommodate the presence of any possible over-dispersion, which frequently occurs in the count responses. This limitation is overcome in a parameter-driven model, where the serial correlation is captured through the latent process using random effects. We compare the results obtained by the two models. A quasi-likelihood approach has been developed to estimate the model parameters. The methodology is illustrated with analysis of two real life datasets. To examine model performance the models are also compared through a simulation study.  相似文献   
54.
This paper proposes a new test statistic based on the computational approach test (CAT) for one-way analysis of variance (ANOVA) under heteroscedasticity. The proposed test was compared with other popular tests according to type I error and power of tests under different combinations of variances, means, number of groups and sample sizes. As a result, it was observed that the proposed test yields better results than other tests in many cases.  相似文献   
55.
This study evaluated the cross‐cultural measurement invariance of the Pediatric Quality of Life Inventory version 4.0 (PedsQL?) among adolescents sampled from Bulgaria, Croatia, India, Indonesia, Nigeria, Serbia, and Turkey. The multiple‐indicator multiple‐cause (MIMIC) model was used, which allowed controlling of demographic variables (i.e., age, gender, and socioeconomic status). Significant effects of country on scores within the PedsQL? domains were observed, with up to 17 items showing differential item functioning (DIF) across the countries. We did not find support for cross‐cultural measurement invariance hypotheses for scores on the PedsQL? adolescent self‐report in this study. Researchers should use caution in making cross‐cultural quality of life comparisons while using the PedsQL.  相似文献   
56.
This paper presents a practical model for firm expansion through franchising. The model allows the possibility of opening both company-owned and franchised stores. The objective is to maximize the expected returns to the franchisor from both types of stores, subject to the total capital outlay budget and the excess capacity available at each warehouse. A relaxation for this problem is studied and a heuristic solution procedure that makes use of this relaxation is developed. Experimental results over a wide range of problem structures show this solution methodology to be very effective, with gaps between feasible solution values and upper bounds generally in the 0 to 1 percent range. An efficient branch-and-bound code also is developed. This code is tested on problems with up to 100 potential store locations and 20 regions. It is found to be at least two orders of magnitude faster than a state-of-the-art commercial integer programming package.  相似文献   
57.
This paper studies demands and expectations of people about the content of the new constitution supposed to be prepared after the parliamentary election of June, 2011 in Turkey. For that purpose, a survey was applied across the country to 6,810 people with different ethnic identities, religious faiths and political tendencies. Economic and social conditions of the respondents were studied and subsequently their tendencies regarding two of the most frequently discussed topics of the country namely Secularism and Republic were explored. For that purpose, statistical technics and the logistic regression technic were used. We interestingly found out that the two principles mentioned above have been substantially accepted by different parts of the society and there are no considerable negative reactions regarding those issues. It was found out in this study that almost all parts of the Turkish society accept some fundamental principles of the regime like Republic and Secularism as well as the Presidency of Religious Affairs. It appears that in Turkey basic differences regarding perspectives on political and social values arise rather from sectarian identities.  相似文献   
58.

The Jaffna Peninsula in Sri Lanka has a generally flat topography with a median elevation of 2.72 m, and thus faces a high risk from sea-level rise that has the potential to have adverse impacts on the livelihoods of coastal communities. Understanding these risks and identifying the regions that could be adversely impacted is critical for planning future settlements and developing preventative protocols where possible. The aim of this study was to analyze the exposure of coastal settlements of the Jaffna Peninsula to climate risks, particularly to sea-level rise, and to identify the areas that are likely to be impacted under different sea-level rise scenarios. Raster-based sea-level rise modeling was performed with a digital elevation model produced with topographic contours and spot heights. The spatial distribution of individual residential houses for the entire Jaffna Peninsula was obtained through manual digitization using virtual globe platforms and high-resolution satellite images, and the houses exposed to inundation under various Representative Concentration Pathways from 2025 to 2100 were identified. The results showed that a majority (55.5%) of the residential buildings in the Jaffna Peninsula are located within 3 m above sea level. Approximately 5554 (5.6%) of the houses were projected to be inundated by 2100, and this projection increased to approximately 25,074 (25.4%) under high tide scenarios. This study highlights the coastal communities with a high level of exposure to coastal inundation where adaptation planning is essential. These results provide insights for coastal managers and policy makers for future planning of new settlements and urban expansion.

  相似文献   
59.
In the real problems, there are many cases which have correlated quality characteristics so multiple response optimization can be more realistic if we can consider correlation structure of responses. In this study we propose a new method which uses multivariate normal probability to find the optimal treatment in an experimental design. Moreover, a heuristic method is used to find better factors’ level in all possible combinations in the designs with large number of controllable factors and their levels. Some simulated numerical examples and a real case were studied by the proposed approach and the comparison of the results with previous methods show efficiency of the proposed method.  相似文献   
60.
Hospital ethics committees (HECs) are typically charged with addressing ethical disputes, conflicts, and dilemmas that arise in the course of patient care. HECs are not widely viewed as having a therapeutic role for health care professionals who experience psychological distress or anticipatory grief in the course of discharging professional duties. A case is presented in which an ethics consultation was requested, chiefly, to secure emotional support for health care professionals who had been asked by a patient to discontinue life-sustaining treatments. As the case demonstrates, HECs may be called upon to provide emotional support and reassurance to health care professionals who willingly carry out psychologically difficult actions, even though these actions may be ethically uncontroversial. In providing this service, the HEC may not necessarily engage in its customary activity of deliberating an ethics issue and resolving a conflict but may still provide valuable assistance, as in the case presented.  相似文献   
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