Query Complexity of Derivative-Free Optimization

This paper provides lower bounds on the convergence rate of Derivative Free Optimization (DFO) with noisy function evaluations, exposing a fundamental and unavoidable gap between the performance of algorithms with access to gradients and those with access to only function evaluations. However, there are situations in which DFO is unavoidable, and for such situations we propose a new DFO algorithm that is proved to be near optimal for the class of strongly convex objective functions. A distinctive feature of the algorithm is that it uses only Boolean-valued function comparisons, rather than function evaluations. This makes the algorithm useful in an even wider range of applications, such as optimization based on paired comparisons from human subjects, for example. We also show that regardless of whether DFO is based on noisy function evaluations or Boolean-valued function comparisons, the convergence rate is the same

How was it for you? A cross-disciplinary study of ‘troublesome knowledge’ as identified by undergraduate students and lecturers in Geography, Medical Science and Psychology

We carried out a small scale pilot study to determine whether participants would spontaneously identify Threshold Concepts (TC’s) and/or troublesome knowledge during open questioning on the characteristics of their disciplines. Students and lecturers reflected upon both easy and difficult aspects of their studies or teaching practice in either group discussions or one-to-one interviews. We compared students and staff observations both within and between the disciplines we examined (Geography, Medical Sciences and Psychology undergraduate degrees). Our intention was to provide specific examples of TC’s within our three disciplines to inform further discussion of embedding the enhancement theme both in our practice and in the learning experiences of our students. Our working hypothesis was that if TC’s exerted an influence on the teaching and learning experience either negatively or otherwise, then we would find ample evidence supplied in our interviews. What we found was that overwhelmingly our interviewees focussed on generic skills-based aspects of teaching and learning. Only three potential content-specific TC’s were offered spontaneously by students and these were all from the discipline of geography

Three and Four Region Multi-sector Linear Modelling Using UK Data : Some Preliminary Results

Scotland and Wales have relatively up-to-date, independently generated, IO tables. These can be separated out from a UK national IO table to construct an inter-regional table. We therefore undertake the detailed analysis at this three-region (Scotland, Wales and the Rest of the UK (RUK)) level, where the Rest of the UK is England and Northern Ireland. However, we also construct a more rudimentary four-region (Scotland, Wales, England and Ireland) set of IO and SAM accounts by constructing a separate Northern Ireland accounts. The inter-regional IO and SAM models are produced for the year 1999. This was determined by the availability of consistent data. In Section II we describe the construction of a three-region Input-Output model for the United Kingdom, which includes the regions of Scotland, Wales and the Rest of the UK (RUK). In Section III we extend the three-region model to construct an inter-regional Social Accounting Matrix. Section IV reports some results using the three-region IO and SAM models. In Section V, we generate a four-region IO and SAM model for the UK, which disaggregates Northern Ireland from the Rest of the UK, and provide some results using the four-region IO and SAM models. Section VI offers our conclusions

In situ observations of trophic behaviour and locomotion of Princaxelia amphipods (Crustacea, Pardaliscidae) at hadal depths in four West Pacific Trenches

Peer reviewedPublisher PD

Genetic Determinism in the Genetics Curriculum: An Exploratory Study of the Effects of Mendelian and Weldonian Emphases

Twenty-first century biology rejects genetic determinism, yet an exaggerated view of the power of genes in the making of bodies and minds remains a problem. What accounts for such tenacity? This article reports an exploratory study suggesting that the common reliance on Mendelian examples and concepts at the start of teaching in basic genetics is an eliminable source of determinism. Undergraduate students who attended a standard “Mendelian approach” university course in introductory genetics on average showed no change in their determinist views about genes. By contrast, students who attended an alternative course which, inspired by the work of a critic of early Mendelism, W. F. R. Weldon (1860-1906), replaced an emphasis on Mendel’s peas with an emphasis on developmental contexts and their role in bringing about phenotypic variability, were less determinist about genes by the end of teaching. Improvements in both the new Weldonian curriculum and the study design are in view for the future

Friends, Neighbours and Distant Partners: Extending or Decentring Family Relationships?

[No abstract][No keywords]

Teaching Teachers for the Future (TTF) Project: Development of the TTF TPACK survey instrument

This paper presents a summary of the key findings of the TTF TPACK Survey developed and administered for the Teaching the Teachers for the Future (TTF) Project implemented in 2011. The TTF Project, funded by an Australian Government ICT Innovation Fund grant, involved all 39 Australian Higher Education Institutions which provide initial teacher education. TTF data collections were undertaken at the end of Semester 1 (T1) and at the end of Semester 2 (T2) in 2011. A total of 12881 participants completed the first survey (T1) and 5809 participants completed the second survey (T2). Groups of like-named items from the T1 survey were subject to a battery of complementary data analysis techniques. The psychometric properties of the four scales: Confidence - teacher items; Usefulness - teacher items; Confidence - student items; Usefulness- student items, were confirmed both at T1 and T2. Among the key findings summarised, at the national level, the scale: Confidence to use ICT as a teacher showed measurable growth across the whole scale from T1 to T2, and the scale: Confidence to facilitate student use of ICT also showed measurable growth across the whole scale from T1 to T2. Additional key TTF TPACK Survey findings are summarised

Active Ranking using Pairwise Comparisons

This paper examines the problem of ranking a collection of objects using pairwise comparisons (rankings of two objects). In general, the ranking of $n$ objects can be identified by standard sorting methods using $n log_2 n$ pairwise comparisons. We are interested in natural situations in which relationships among the objects may allow for ranking using far fewer pairwise comparisons. Specifically, we assume that the objects can be embedded into a $d$-dimensional Euclidean space and that the rankings reflect their relative distances from a common reference point in $R^d$. We show that under this assumption the number of possible rankings grows like $n^{2d}$ and demonstrate an algorithm that can identify a randomly selected ranking using just slightly more than $d log n$ adaptively selected pairwise comparisons, on average. If instead the comparisons are chosen at random, then almost all pairwise comparisons must be made in order to identify any ranking. In addition, we propose a robust, error-tolerant algorithm that only requires that the pairwise comparisons are probably correct. Experimental studies with synthetic and real datasets support the conclusions of our theoretical analysis.Comment: 17 pages, an extended version of our NIPS 2011 paper. The new version revises the argument of the robust section and slightly modifies the result there to give it more impac

Reflexivity in quantitative research: A rationale and beginner's guide

Reflexivity is the act of examining one's own assumptions, beliefs, and judgments, and thinking carefully and critically about how these influence the research process. The practice of reflexivity confronts and questions who we are as researchers and how this guides our research. It is central in debates on objectivity, subjectivity, and the very foundations of social science research and generated knowledge. Incorporating reflexivity in the research process is traditionally recognized as one of the most notable differences between qualitative and quantitative methodologies. Qualitative research centres and celebrates participants’ lived experience, and qualitative researchers are readily encouraged to consider how their own positionalities inform the research process, forming an important part of qualitative research training. Quantitative methodologies in social and personality psychology, on the other hand, have remained seemingly detached from this level of reflexivity and general reflective practises. In this commentary, we, three quantitative researchers who have grappled with the compatibility of reflexivity with our research, argue that reflexivity has much to offer quantitative methodologists, in social and personality psychology and beyond. The act of reflexivity prompts researchers to acknowledge and centre their positionalities, encourages a more thoughtful engagement with every step of the research process, and thus, as we argue, contributes to the ongoing reappraisal of openness and transparency in psychology. In this paper, we make the case for integrating reflexivity across all research approaches, before providing a ‘beginner’s guide’ for quantitative researchers wishing to engage reflexivity within their work, providing concrete recommendations, worked examples, and reflexivity prompts