Service learning and the practice of social justice and care

The values of a social justice pedagogy in teacher education are assumed to be firmly established in South African higher education. This article discusses how serviced learning (SL) can provide practical experience of caring and serve the promotion of the ideals of social justice in two initial teacher education programmes. However, an analysis of data in this case study shows that, although SL practice has served as a platform for social justice and for care as two basic educational values, participants were not yet able to verbalize and theorize these values. They were also not able to embed these values in their reflection about service as an inherent component of education. With data from different role players in a number of SL projects, we show that the students’ discourse of what it means to be a caring teacher in a just society has not yet been developed despite the successful practical experience. It was found that, although the students had been building a practice ‘platform’ for service, they had not yet been able to articulate the conceptual intersect of care and social justice clearly. With this epistemological notion in mind, two main themes from the data analysis are discussed: 1) How SL shifted student learning from ideas ‘about’ service to implemented service, and 2) how the practical experience promoted reciprocity in inter-institutional and inter-generational communities of practice.     

The value of the aggregate data approach in meta-analysis with time-to-event outcomes

Collecting individual patient data has been described as the 'gold standard' for undertaking meta-analysis. If studies involve time-to-event outcomes, conducting a meta-analysis based on aggregate data can be problematical. Two meta-analyses of randomized controlled trials with time-to-event outcomes are used to illustrate the practicality and value of several proposed methods to obtain summary statistic estimates. In the first example the results suggest that further effort should be made to find unpublished trials. In the second example the use of aggregate data for trials where no individual patient data have been supplied allows the totality of evidence to be assessed and indicates previously unrecognized heterogeneity.     

WinBUGS - A Bayesian modelling framework: Concepts,structure, and extensibility

WinBUGS is a fully extensible modular framework for constructing and analysing Bayesian full probability models. Models may be specified either textually via the BUGS language or pictorially using a graphical interface called DoodleBUGS. WinBUGS processes the model specification and constructs an object-oriented representation of the model. The software offers a user-interface, based on dialogue boxes and menu commands, through which the model may then be analysed using Markov chain Monte Carlo techniques. In this paper we discuss how and why various modern computing concepts, such as object-orientation and run-time linking, feature in the software's design. We also discuss how the framework may be extended. It is possible to write specific applications that form an apparently seamless interface with WinBUGS for users with specialized requirements. It is also possible to interface with WinBUGS at a lower level by incorporating new object types that may be used by WinBUGS without knowledge of the modules in which they are implemented. Neither of these types of extension require access to, or even recompilation of, the WinBUGS source-code.     

Radical Normals: The Moral Career of Straight Parents as Public Advocates for Their Gay Children

Sociological research has examined straight parents in “traditional” family arrangements who become gay rights activists, but pays insufficient attention to how this puzzling identity comes into being. Drawn from observations and interviews of parents participating in a local chapter of Parents and Friends of Lesbians and Gays (PFLAG) (2009 to 2010), this paper analyzes the parenting activities undertaken by straight parents of gay children as a moral career, involving stages of acceptance that can lead to eventual public advocacy. Paradoxically, these parents become radical normals through these stages; that is to say, they “do” the work of parenting by becoming gay rights advocates, motivated by commitments to conventional imperatives of loving and supporting a child. Using the conceptual scaffolding of the moral career, this paper identifies the mechanisms that move parents through these different career stages.     

Crown width models for woody plant species growing in urban areas of the U.S.

Urban Ecosystems - Crown widths of woody plant species growing in urban areas are of considerable importance as an overall indicator of health and also serve as an important factor for assessing...     

A parameterized perspective on packing paths of length two

We study (vertex-disjoint) packings of paths of length two (i.e., of P ₂’s) in graphs under a parameterized perspective. Starting from a maximal P ₂-packing ℘ of size j we use extremal combinatorial arguments for determining how many vertices of ℘ appear in some P ₂-packing of size (j+1) (if such a packing exists). We prove that one can ‘reuse’ 2.5j vertices. We also show that this bound is asymptotically sharp. Based on a WIN-WIN approach, we build an algorithm which decides, given a graph, if a P ₂-packing of size at least k exists in time O^*(2.448^3k)\mathcal{O}^{*}(2.448^{3k}) .     

A short proof of a result on a Vizing-like problem for integer total domination

In this note, we provide a short proof of a recent result on a Vizing-like problem for integer total domination in graphs given by Li and Hou (J. Comb. Optim., 2008).     

Analysis of ranked data in randomized blocks when there are missing values

Data consisting of ranks within blocks are considered for randomized block designs when there are missing values. Tied ranks are possible. Such data can be analysed using the Skillings–Mack test. Here we suggest a new approach based on carrying out an ANOVA on the ranks using the general linear model platform available in many statistical packages. Such a platform allows an ANOVA to be calculated when there are missing values. Indicative sizes and powers show the ANOVA approach performs better than the Skillings–Mack test.     

A characterization of graphs with disjoint dominating and paired-dominating sets

A dominating set of a graph is a set of vertices such that every vertex not in the set is adjacent to a vertex in the set, while a paired-dominating set of a graph is a set of vertices such that every vertex is adjacent to a vertex in the set and the subgraph induced by the set contains a perfect matching. In this paper, we provide a constructive characterization of graphs whose vertex set can be partitioned into a dominating set and a paired-dominating set.