Modelling two types of heterogeneity in the analysis of student success

ABSTRACT

Student dropout is a worldwide problem, leading private and public universities in developed and underdeveloped countries to study the subject carefully or, as has recently been done, to analyse what drives student success. On this matter, different approaches are used to obtain useful information for decision-making. We propose a model that considers the enrolment date to the dropout or graduation date and also covariates to measure student success rates, to identify what the academic and non-academic factors are, and how they drive the student success. Our proposal assumes that there is one part of the population who is not at risk of dropping out, and that the part of the population at risk is heterogeneous, that is, we assume two types of heterogeneity. We highlight two advantages of our model: one is to identify the period of higher risk to dropout due to considering the academic survival time and the second is due to the inclusion of covariates that enable us to identify the characteristics linked to dropout. In this research, we also demonstrate the identifiability of the model and describe the estimation procedures. To exemplify the applicability of the approach, we use two real datasets.     

Effective social education of exclusion: contributions from social pedagogy

The objective of this research was to identify effective strategies for socio-educational intervention with adolescents aged 12–16 years in a situation of social risk and provide some proposals from the field of social pedagogy. The research was conducted in three autonomous regions of Spain—Madrid, Galicia and Catalonia—between 2011 and 2013 and used the grounded theory approach. Thirty one practitioners and 19 adolescents participated in the focus groups and interviews. The main results suggest central strategies related to the empowerment and participation of adolescents, resilience and the flexible planning of interventions, with relevant implications for practice and policies.     

The Practice of Puxa-Puxa among Mozambican Women: A Systematic Inventory of Motives

Puxa-puxa is the elongation of the labia minora of the genital organs. It is one of the most widespread genital practices among women in Mozambique, and the practice seems to be specific to this country. The motives underlying this practice and its abandonment were examined in a theory-driven way. A total of 616 women currently living in the provinces of Maputo, Zambezia, and Nampula, aged 18 to 62, were presented with one of two questionnaires that contained items about possible motives for practicing puxa-puxa or possible motives for not practicing it. Seven separable motives for practicing puxa-puxa were found, and the most highly rated were “Having a satisfying sexual life”; “Satisfying my sexual partner”; and “Gaining self-control.” Five separable motives for not practicing puxa-puxa were found, and the most highly rated were “Disliking a painful practice”; “Affirming one's value as a person”; and “Avoiding contamination.” The main findings of the study are that the practice of puxa-puxa is associated with deep psychological motives common to most women in most cultures, namely having a satisfying sexual life with a reliable partner, creating the conditions for having children, and being able to care for them. The abandonment of this practice is largely the result of personal decisions, which are not taken under constraint and which are not exclusively taken from fear of illness.     

Performance of asymmetric links and correction methods for imbalanced data in binary regression

In binary regression, imbalanced data result from the presence of values equal to zero (or one) in a proportion that is significantly greater than the corresponding real values of one (or zero). In this work, we evaluate two methods developed to deal with imbalanced data and compare them to the use of asymmetric links. The results based on simulation study show, that correction methods do not adequately correct bias in the estimation of regression coefficients and that the models with power links and reverse power considered produce better results for certain types of imbalanced data. Additionally, we present an application for imbalanced data, identifying the best model among the various ones proposed. The parameters are estimated using a Bayesian approach, considering the Hamiltonian Monte-Carlo method, utilizing the No-U-Turn Sampler algorithm and the comparisons of models were developed using different criteria for model comparison, predictive evaluation and quantile residuals.     

Therapeutic Use of Fact Sheets in Family Therapy with Children and Adolescents With Functional Somatic Symptoms

Functional somatic symptoms signal distress and reflect an activation of the body's stress‐regulation systems. Many different types of stressors – physical, emotional or both – may activate the body's stress‐regulation systems. If stress‐related disruptions are extreme or are not limited in time, functional somatic symptoms may emerge, signalling that the body remains in a state of activation and somatic distress. In this paper, we describe the development of therapeutic fact sheets, which are used as part of our multimodal, family‐based, rehabilitation intervention for children and adolescents presenting with functional somatic symptoms. The fact sheets provide information about functional somatic symptoms – including their assessment and treatment – from a stress‐system framework. They are used in the context of a family intervention to facilitate engagement with the family and to reduce parental anxiety and reactivity. Whilst the fact sheets were initially developed for parents, over time we found that the sheets were also useful in managing anxiety in the medical and school systems. A key goal of this article is to share this resource with other clinicians working with children/adolescents with functional somatic symptoms.     

Engineer-to-order (ETO) production planning and control: an empirical framework for machinery-building companies

This paper illustrates the results of an empirical study involving 21 engineer-to-order (ETO) companies, operating in the machinery-building industry. The study investigates the needs and requirements of such companies in terms of software support for governing the businesses, with particular emphasis on production planning and control (PPC) processes. An empirical analysis investigated two main aspects: (i) the set of business activities performed by the companies in the analysed industry and (ii) the relevant, high-level software functionalities required for the execution of such activities. As an answer to the observed compelling need for reviewing the general approaches to PPC in machinery-building companies, we develop an empirical, high-level production planning and scheduling reference framework, encompassing all the activities involved in the order fulfilment process.     

Exit is the answer: The political nature of Central American migration

This article provides evidence that many Central Americans who have joined the migrant caravans to the north manifest a profound discontent with the political institutions of their home countries. It is based on surveys with migrants in refugee centres, compared with similar data from the AmericasBarometer survey, and complemented with contextual qualitative data on the experience of immigrants passing through Mexico. The article shows that several Central Americans in route to the north do not trust their political institutions and express little support for their political system. It demonstrates that in contexts where economic instability, rampant crime, and environmental uncertainty prevail, many citizens keep exiting their countries under the conviction that government institutions have lost the capability to protect them from existential threats.     

WILL THE EUROPEAN COMMUNITY MAKE THE 1992 DEADLINE ON THE ABOLITION OF INTERNAL BORDER CONTROLS ?

The efforts by the 12 European countries to develop a single market are in jeopardy because of several factors including a failure to come to agreement on the Schengen Supplementary Agreement. If this agreement is not signed soon, the deadline of January 1, 1993 for the opening of the borders will pass. If this occurs, it will signify a failure of the 1st great test of European unity. The Schengen group includes the Benelux, FRG, and France, Italy (as of November 1991), and will probably include Spain and Portugal by June 1991. The primary reason for this trouble stems from the lack of parliamentary control during the negotiation process. Other problems stem from a failure to come to an agreement about the text of the agreement in regards to asylum seekers. The Agreement is not allowed to be modified by signatory States, they must either ratify it or not. There is a great deal of pressure to change this aspect of the Agreement, because it is felt by many that is abandons sovereignty about a crucial issue like frontier borders. Harmonizing rules of entry and granting of asylum are the 2 most powerful forces motivating people to fight against Community competency. Part of this problem is that the number of asylum seekers is growing rapidly and international rules of human rights are conflicting with the vested interests of the member states. Another source of discord was the Group of Coordinators's Palma Document which was approved by the European Council. In it, measures without consensus were called desirable, and those that could be approved were called essential. This way of doing things still created a democratic deficit and maintained the incoherent plan to lift internal borders. Decisive actions are required during the 2nd half of 1991 if the deadline is to be met because the rotating presidency goes to Portugal next. Portugal does not have the political power necessary to finalize the agreement. Denmark is then next after Portugal and is even less interested in coming to agreement than the UK. Therefore, if the agreement is to succeed it must be do so quickly or else suffer from political weakness.     

爱、幸福与命运——我的中国故事

几年前9月的一个夜晚，我来到上海，只携带着一些衣服和书来到了中国。开始了对未知国度的体验之旅，这悄然改变了我、我的人生、甚至还改变了我原本看待世界的方式。     

Are young people in the Philippines taking chances with HIV / AIDS?

The numbers of AIDS cases and HIV infections detected in the Philippines have risen slowly but steadily since the first AIDS case in the country was diagnosed in 1984. By the end of 1995, 234 AIDS cases and 470 HIV infections had been reported to the country's Department of Health. However, given the limited extent to which people have been tested for HIV infection, there are most likely many more cases than reported. The HIV/AIDS epidemic is spreading within the Filipino population. The country's substantial commercial sex trade, reports suggesting that many unmarried young men have sexual intercourse with girlfriends and acquaintances, and IV drug use among a small number of young people are factors which contribute to the potential for a serious HIV/AIDS epidemic in the Philippines. Findings from the 1994 national Young Adult Fertility and Sexuality Study, a household survey covering 10,879 men and women aged 15-24 years in 959 different communities, are presented. Almost all respondents had heard of AIDS, but there was some degree of ignorance and misinformation on the modes of HIV transmission. 13% of all single men reported having had only one sex partner, 10% reported two or more partners, and 3% reported five or more. 98% of sexually active men had heard of condoms, 58% knew that condom use can protect against HIV infection, 23% reported ever having used one, and 4% reported using a condom during the most recent act of sexual intercourse.