A comparison of approaches for estimating the effect of women's education on the probability of using modern contraceptive methods in Malawi

The aim of this study is to estimate the effect of education on the probability of married Malawian women using modern contraceptive methods by accounting for both observed and unobserved confounders. We conduct a sensitivity analysis and compare the results of naive models with instrumental variable models to account for the potential endogeneity of education. Our findings demonstrate conflicting results between the two modelling approaches. The naive models report smaller education effects on the probability of using modern contraceptive methods compared to instrumental variable models. We also find that by relaxing the functional form assumption on the effect of continuous covariates, using a flexible instrumental variable model, the education's effect follows a positive, nonlinear pattern. This finding is not observed with a classic instrumental variable model.     

Modified chain sampling plans for lot inspection by variables and attributes

The purpose of acceptance sampling is to develop decision rules to accept or reject production lots based on sample data. When testing is destructive or expensive, dependent sampling procedures cumulate results from several preceding lots. This chaining of past lot results reduces the required size of the samples. A large part of these procedures only chain past lot results when defects are found in the current sample. However, such selective use of past lot results only achieves a limited reduction of sample sizes. In this article, a modified approach for chaining past lot results is proposed that is less selective in its use of quality history and, as a result, requires a smaller sample size than the one required for commonly used dependent sampling procedures, such as multiple dependent sampling plans and chain sampling plans of Dodge. The proposed plans are applicable for inspection by attributes and inspection by variables. Several properties of their operating characteristic-curves are derived, and search procedures are given to select such modified chain sampling plans by using the two-point method.     

Preverbal Infants' Ability to Encode the Outcome of Distributive Actions

This research examined whether 10‐month‐old infants expect agents to perform equal distribution of resources. In Experiment 1, infants saw a distributor performing either an equal distribution where one strawberry was given to each of two recipients, or an unequal distribution that favored one of the recipients. Infants looked longer at the unequal test event, suggesting that they expected the strawberries to be distributed equally. In Experiment 2, the potential recipients were replaced with inanimate objects to rule out a lower‐level alternative explanation of the results in Experiment 1 based on symmetric movement of the distributor. Infants' looking times did not reveal a preference for one of the two outcomes of the test events (i.e., symmetric or asymmetric movement). Experiment 3 controlled for the role of the distributive action, that is, here the distributors only removed barriers revealing strawberries that the recipients already had. No preference was observed when an equal or unequal initial allocation of resources was revealed. Experiment 4 assessed whether infants relied on affiliative information provided by the distributor's movements. The distributor made the same movements as in Experiment 1, but without distributing any strawberries, and no difference in looking times was observed. These findings support the view that preverbal infants expect agents to behave according to a simple principle: Resources are to be distributed equally among equivalent recipients. We discuss the possible links between such reactions and the emergence of an early sense of fairness.     

Testing for Serial Independence: Beyond the Portmanteau Approach

Portmanteau tests are typically used to test serial independence even if, by construction, they are generally powerful only in presence of pairwise dependence between lagged variables. In this article, we present a simple statistic defining a new serial independence test, which is able to detect more general forms of dependence. In particular, differently from the Portmanteau tests, the resulting test is powerful also under a dependent process characterized by pairwise independence. A diagram, based on p-values from the proposed test, is introduced to investigate serial dependence. Finally, the effectiveness of the proposal is evaluated in a simulation study and with an application on financial data. Both show that the new test, used in synergy with the existing ones, helps in the identification of the true data-generating process. Supplementary materials for this article are available online.     

Are We Educating Creative Professionals? The Results of Some Experiments on the Education of Social Work Students in Italy

Creativity is a competence crucial for the practice of social work. In particular, it is associated with a greater ability to solve complex problems and to learn, and it is considered to be an integral element of the professional identity of social workers. Nevertheless, in the past 20 years, neoliberal policies and bureaucratization have promoted models of education focused more on technical skills than on imaginative and ideational capacities. This article presents the results of two experiments conducted to determine the effects on creativity and imagination of the technical education of social workers. The results show that creativity is not a variable independent of the type of education delivered to students and that educational programmes which emphasise only the technical dimension of social work can have a direct influence on the creative abilities of students. It is therefore necessary to strike the right balance between education aimed at the acquisition of technical skills and education that promotes creativity.     

Education and Life Satisfaction in Relation to the Probability of Social Trust: a Conceptual Framework and Empirical Analysis

We employ cross-sectional microdata from 2010 through 2012 collected by the Italian National Institute of Statistics to investigate the proposed conceptual framework regarding the joint relationship between education, life satisfaction and the probability of social trust. The analysis has been carried out using two alternative specifications of the logit model: parametric and semiparametric. Our findings suggest that (a) both modelling methods that we utilise yield consistent results in terms of the positive effects of education and life satisfaction on social trust; (b) for unsatisfied individuals, social trust is generally low and largely unresponsive to the individual’s education level, whereas for ‘sufficiently satisfied’ individuals, social trust increases strongly with education; (c) there are some gender differences in the joint relationship between education, life satisfaction and social trust and (d) the parametric approach tends to mask some interesting patterns that are captured by the semiparametric specification. This finding implies that the parametric approach leads to a biased interpretation of the results, with an apparent failure of some of the assumptions made in the conceptual framework.     

The Place of Construction in Sociological Realism

In the contemporary epistemological debate on social reality, characterized by the crisis of post‐modern theories and the emergence of new forms of realism, are there any approaches not acknowledging some specific ontological character to the construction of social objects? The question is apparently rhetorical, but the implication of this problem are not obvious. In the sociological literature the opposition between reality and construction is not clearly defined. Sometimes it is considered a dichotomy, in other situations the synthesis of alternative theses in a dialectical horizon. The more systematic attempt considers reality and construction as analytical macro‐dimensions where the relation between social ontology and epistemology operates. From this stance, the acknowledgement of the role of social construction in a wider realist horizon is the true overtaking of postmodern philosophy. If it is true that facts exist beyond representations, it is also true that representations themselves have a specific effect on reality, who continually re‐structures itself around specific relations of emergent power. Stating that reality is socially constructed is an evident limit of postmodern theories. On the other hand, stating that only facts exist constitute an impoverishment of realism and its replacement in neo‐positivism. Social phenomena are real because they are based on specific properties of the inter‐subjective construction of social reality. This thesis represents the revitalization of an advanced, anti‐positivistic realism and the definition of the specificity of social objects. The aim of this essay is to search for a specific place of construction within the development of realist social ontology.     

Analysis of the spread of Rhynchophorus ferrugineus in an urban area,using GIS techniques: a study case in Central Italy

Urban Ecosystems - The spread of the red palm weevil is now a very severe problem on a global scale. In this paper, we investigate its spread during the 2007–2013 period in a coastal urban...     

Model-based clustering with sparse covariance matrices

Statistics and Computing - Finite Gaussian mixture models are widely used for model-based clustering of continuous data. Nevertheless, since the number of model parameters scales quadratically with...