The role of financing frictions in agricultural investment decisions: an analysis pre and post financial crisis

This paper uses a fundamental Q model of investment to consider the role played by financing frictions in agricultural investment decisions, controlling econometrically for censoring, heterogeneity and errors-in-variables. Our findings suggest that farmer's investment decisions are not driven by market fundamentals. We find some evidence that debt overhang restricts investment but investment is not dependent on liquidity or internal funds. The role of financing frictions in determining investment decisions changes in the post-financial crisis period when debt overhang becomes a significant impediment to farm investment. The evidence suggests that farmers increasingly rely on internal liquidity to drive investment. Finally, we find no evidence that farmers use on-farm capital to fund on-farm investment.Credit Constraints, Firm Level Investment, Tobin's Q, Debt, Agricultural Finance, G31, G32, F34,

Coding classroom dialogue: Methodological considerations for researchers

Systematic analysis or coding of classroom dialogue is useful for assessing the role of high-quality interaction in supporting learning. However, although coding is an immensely complex and cognitively demanding activity that has taxed researchers over decades, the methodological challenges are often not discussed or problematised in empirical reports. Accordingly, this paper aims to help researchers make sense of the challenges, strengths and practical applications of using systematic coding schemes for analysing classroom dialogue. It presents an in-depth analysis of the pros and cons of contrasting approaches and the key methodological considerations, including scope, grain size, reliability and validity. It goes on to provide a worked example, illustrating how one team tackled the challenges in adapting for a new research objective an earlier coding scheme developed for use across diverse contexts. Two original, theory-informed analytic tools created to study the relationship between dialogic teaching and student learning in English primary schools are shared and made available for others’ use or adaptation. The paper offers practical guidance for developing or adapting coding schemes for different research purposes. It highlights the need for further precision and critical attention to the ways in which scholars are investigating dialogic practices intended to support learning.ESR

Linearity in the non-deterministic call-by-value setting

We consider the non-deterministic extension of the call-by-value lambda calculus, which corresponds to the additive fragment of the linear-algebraic lambda-calculus. We define a fine-grained type system, capturing the right linearity present in such formalisms. After proving the subject reduction and the strong normalisation properties, we propose a translation of this calculus into the System F with pairs, which corresponds to a non linear fragment of linear logic. The translation provides a deeper understanding of the linearity in our setting.Comment: 15 pages. To appear in WoLLIC 201

Self-tuned quantum dot gain in photonic crystal lasers

We demonstrate that very few (1 to 3) quantum dots as a gain medium are sufficient to realize a photonic crystal laser based on a high-quality nanocavity. Photon correlation measurements show a transition from a thermal to a coherent light state proving that lasing action occurs at ultra-low thresholds. Observation of lasing is unexpected since the cavity mode is in general not resonant with the discrete quantum dot states and emission at those frequencies is suppressed. In this situation, the quasi-continuous quantum dot states become crucial since they provide an energy-transfer channel into the lasing mode, effectively leading to a self-tuned resonance for the gain medium.Comment: 4 pages, 4 figures, submitted to Phys. Re

BJET Editorial for the 50th Anniversary Volume in 2019: Looking back, reaching forward

The Editors are thrilled to introduce the 50th Anniversary volume of the British Journal of Educational Technology (BJET). This momentous milestone has spurred us to share with the readership our pride and sense of responsibility for editing one of the top journals in the field

Teacher–Student Dialogue During Classroom Teaching: Does It Really Impact on Student Outcomes?

It is now widely believed that classroom dialogue matters as regards student outcome, with optimal patterns often regarded as requiring some or all of: open questions; elaboration of previous contributions; reasoned discussion of competing viewpoints; linkage and coordination across contributions; meta-cognitive engagement with dialogue; high student participation. To date however, the relevance of such features has been most convincingly examined in relation to small-group interaction amongst students; little is known about applicability to teacher-student dialogue. The paper reports a large-scale study that permits some rebalancing. The study revolves around the two lessons (covering two of mathematics, literacy and science) that were video-recorded in each of 72 demographically diverse classrooms (students aged 10-11 years). Key measures of teacher-student dialogue were related to six indices of student outcome, which jointly covered curriculum mastery, reasoning, and educationally relevant attitudes. Prior attainment and attitudes were considered in analyses as were other factors, e.g. student demographics and further aspects of classroom practice, that might confound interpretation of dialogue-outcome relations. So long as students participated extensively, elaboration and querying of previous contributions were found to be positively associated with curriculum mastery, and elaboration was also positively associated with attitudes.ESR

BJET Editorial November 2016

Greetings to the BJET community from the new editorial team. We took over in July 2016 and are excited about the opportunity to lead and shape this esteemed journal. In this editorial we outline our policies and vision for the future and report on our first few months in post

Dialogic practices in primary school classrooms

Research into classroom dialogue suggests that certain forms are especially productive for students’ learning (Howe and Abedin, 2013). Despite the large number of studies in this area, there is inadequate evidence about the prevalence of the identified forms, let alone their productivity. However, scarcity is widely presumed. The overall aim of the study reported in this paper was to examine the extent to which the forms are embedded within current practice in UK primary schools. Video-recordings of two lessons from each of 36 classrooms formed the database, with two subjects from mathematics, English and science covered in each classroom. Each lesson was coded per turn for the presence of ‘dialogic moves’ and rated overall for the level of student involvement in specified activities. Results revealed that the supposedly productive forms were not always as scarce as sometimes presumed, while also highlighting huge variation in their relative occurrence. They also point to the role of professional development for teachers in promoting use of some forms