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When waiting makes sense: how consumer anticipation affects later evaluations
Get PDFThis paper addresses a gap in knowledge about consumer anticipation. We build on the negative discount model (Loewenstein, 1987) which notes that utility may be gained through deferred consumption; the utility of looking forward to, and savoring forthcoming pleasant consumption adds to the total utility of the consumption episode. However, little is known about (1) the mental mechanisms involved in consumer anticipation, and their intensity, that underlie this effect, and (2) how evaluation of the object of anticipated consumption evolves over time, from the beginning of the anticipation period to post-consumption. Specifically, we ground our research in theories of attitude formation and change to investigate the circumstances in which evoking intense anticipation produces long-lasting and robust positive attitude.
From the literature, we develop hypotheses relating information provision and anticipation intensity to subsequent attitude change between pre- and post-consumption stages. We test hypotheses in five studies, in two cultural contexts involving pleasant anticipated consumption. We use an experimental approach manipulating real consumption experiences, recording attitudes pre- and post-consumption. We find that an “anticipation effect” on subsequent evaluations is explained by intensity of anticipation, which is driven by provision of information. We also note that a long-term desirable effect of anticipation is observed, irrespective of whether the core consumption experience was positive or negative
Impact of dietary forage proportion and crossbreeding on feed efficiency and methane emissions in lactating dairy cows
Get PDFIncreasing forage proportion (FP) in the diets of dairy cows would reduce competition for human edible foods and reduce feed costs, particularly in low-input systems. However, increasing FP reduces productivity and may increases methane (CH4) emissions parameters. This work aimed to investigate the impact of FP and breed on feed efficiency and CH4 emission parameters. Data from 32 individual experiments conducted at the Agri-food and Biosciences institute between 1992 and 2010 were utilised in this study resulting in data from 796 Holstein-Friesian (HF), 50 Norwegian Red (NR), 46 Jersey x HF (J×HF) and 16 NR × HF cows. Diets consisted of varying proportions of forage and concentrate dependent on the experimental protocols of each experiment. A linear mixed model was used to investigate the effect of low (LFP; 10% to 30%), medium (MFP; 30% to 59%), high (HFP; 60% to 87%) and pure (FOR; 100%) FP (DM basis) and breed on feed efficiency, and CH4 emission parameters and multivariate redundancy analysis identified associations between animal and dietary drivers on the same variables. Total DMI (kg/d) was higher for cows offered LFP (17.3) and MFP (17.9) compared to HFP (15.3) and FOR (13.8) (P<0.001). Milk yield (kg/d) (P<0.001), milk yield/DMI (kg/kg) (<0.001), ECM/DMI (kg/kg) (P<0.001) and milk energy/DMI (MJ/kg) (P<0.001) were higher for LFP and MFP compared to HFP and FOR. Methane/DMI (g/kg) was higher for HFP (24.3) compared to MFP (22.4) (P<0.001). Methane/milk yield (g/kg) (P<0.001) or CH4/ECM (g/kg) (P<0.001) was higher for HFP (22.5 or 21.6) and FOR (27.0 or 25.8) compared to MFP (19.1 or 17.9). There were no differences between LFP and MFP or between HFP and FOR for milk yield (kg/d), milk yield/DMI, ECM/DMI, milk energy/DMI, CH4/milk yield and CH4/ECM. Differences existed between breeds for residual feed intake (P=0.040), milk yield/DMI (P=0.041) and CH4/DMI (P=0.048) with multivariate redundancy analysis demonstrating negative correlations with efficiency and positive correlations with CH4/DMI and CH4/milk yield. Feeding concentrates at 70% to 90% of DMI (present LFP group) would not result in any further benefits for productivity, feed efficiency or CH4 yield and intensity when compared to feeding 41% to 70% concentrates of DMI (present MFP group). There may be opportunity to improve profitability for lower intensity farms with less concentrate input
Closing ranks: the Publishers Association in Victorian Britain and its powerful place in institutional formation
Get PDFProfessional associations have been explored as institutional agents and can be powerful mechanisms for instigating practices into an industry. Despite this identification there is a lack of research which delves deeper and explores the contexts that allow strategies which contribute to institutional formation; which in turn can create professional associations in the process. Through an analysis of archival letters and newspaper articles surrounding the formation of the net book agreement in the Victorian British publishing industry, this paper illustrates how individuals formed the Publishers Association to further their own causes and protect their business interests. This paper argues that the construction of the professional association was used as the vehicle for individuals with the most power in the Victorian publishing industry to instigate change
Single-stage portfolio optimization with automated machine learning for M6
No full textThe goal of the M6 forecasting competition was to shed light on the efficient market hypothesis by evaluating the forecasting abilities of participants and their investment
strategies. In this paper, we challenge the ‘estimate-then-optimize’ approach with one that directly optimizes portfolio weights from data. We frame portfolio selection as
a constrained penalized regression problem. We present a data-driven approach that automatically performs model selection and hyperparameter tuning to maximize the
objective without noisy or potentially misspecified intermediate steps. Finally, we show how the portfolio weights can be optimized using the Method of Moving Asymptotes. Testing on the M6 competition data, our approach achieves a global rate of return of 9.5% and an information ratio of 5.045, which is in stark contrast to the mean IR of
the M6 competition teams of -3.421 and the IR of 0.453 for the M6 benchmark
The spatial interlocking of commercial office real estate and advanced producer services: a central flow theory lens
Get PDFThe paper extends geographical enquiry into the external urban relations described by central flow theory in an exploration of the roles of commercial office real estate (CORE) and advanced producer services (APS) as a conduit for inter-city flows of finance in corporate globalization. The analysis investigates and benchmarks the spatial overlap between these city-based service networks and uses this to consider how their respective servicing strategies influence international capital flows. We find that the networks are interlocked, as the connectivity in one network can significantly explain the connectivity in the other. Both CORE and APS services promote cross-border flows of finance. Cities providing multinational CORE and APS services are able to articulate direct as well as indirect inter-city capital flows and spillovers to non-service sectors
Polymer-protected gold nanoparticles for photothermal treatment of Ehrlich Adenocarcinoma: in vitro and in vivo studies
Get PDFPhotothermal therapy (PTT) is recognized as an effective tool for the treatment of cancer and it has attracted considerable attention of scientists. In this work, gold nanospheres (AuNSs) and gold nanorods (AuNRs) stabilized using poly(N-vinylpyrrolidone) (PVP), pristine gellan gum (PGG), and poly(2-ethyl-2-oxazoline)-grafted gellan gum (GG-g-PEtOx) are synthesized and evaluated as PTT agents in Ehrlich cancer cells. The physicochemical characteristics of these AuNSs and AuNRs, including their surface plasmon resonance absorption spectra, size, zeta potential, and aspect ratio are studied using UV–vis-spectroscopy, dynamic light scattering, zeta potential, transmission electron microscopy, and optical microscopy techniques. The polymer-protected AuNSs exhibit light-to-heat conversion, raising the temperature from 37 to 43 °C when irradiated using a visible light source. In the case of AuNSs, considerable damage to Ehrlich cancer cells is observed following irradiation and 40 days of examination. However, with regard to AuNSs, the damage to Ehrlich cancer cells is slightly lower than observed in AuNRs. In vivo experiments demonstrate that laser irradiation of tumors in mice after injecting AuNSs leads to a statistically significant decrease in tumor size as compared to those not irradiated and the control samples
Developing an ontology-based tool for relating risks to the energy performance gap in buildings
Get PDFDespite extensive research on the underlying reasons for the energy performance gap in buildings, there is a critical need for stakeholders to standardize and facilitate the use of this knowledge and support its broader application by machines. Our research addresses this gap by developing both an ontology and a tool to utilize risk information regarding the performance gap in buildings. Research into this topic began with the creation of an energy- performance gap-risk ontology for new and existing buildings using the METHONTOLOGY method. This comprised a comprehensive literature review and semi-structured interviews with ten experts concerning six buildings, in order to develop taxonomies and define risk factor interactions. It was followed by a three-stage validation using a mixed-method research methodology. Steps included comparing the ontology with a similar empirical study, gathering expert opinions via interviews and ratings assessments, and finally, interviewing an experienced professional to ascertain whether there were any concepts not covered by the ontology. The taxonomies were modeled in Protégé 5.5, and using the ontology, a spreadsheet tool was developed using Microsoft Visual Basic for Applications in Excel.
The ontology identified 36 primary risk factors, and a total of 95 when including additional risks linked to certain factors. Factors such as professional liability insurance, stakeholder motivation, effective communication, experience, training, integrated design, simplicity of detailing, building systems or design, and project commissioning can help manage the performance gap in buildings. The tool developed serves as a decision-support system, offering features like project risk checklists to assist stakeholders in addressing the performance gap. This study is the first to develop an energy performance gap-risk ontology and a tool to help project stakeholders collect, store, and share building risk information
Developing robust incomplete Cholesky factorizations in half precision arithmetic
Get PDFIncomplete factorizations have long been popular general-purpose algebraic preconditioners for solving large sparse linear systems of equations. Guaranteeing the factorization is breakdown free while computing a high quality preconditioner is challenging. A resurgence of interest in using low precision arithmetic makes the search for robustness more important and more challenging. In this paper, we focus on ill-conditioned symmetric positive definite problems and explore a number of approaches for preventing and handling breakdowns: prescaling of the system matrix, a look-ahead strategy to anticipate breakdown as early as possible, the use of global shifts, and a modification of an idea developed in the field of numerical optimization for the complete Cholesky factorization of dense matrices. Our numerical simulations target highly ill-conditioned sparse linear systems with the goal of computing the factors in half precision arithmetic and then achieving double precision accuracy using mixed precision refinement. We also consider the often overlooked issue of growth in the
sizes of entries in the factors that can occur when using
any precision and can render the computed factors
ineffective as preconditioners
The connoisseur’s emancipation of dissonance: how changing the experience of musical tension can inform individual responses to organizational paradoxes
Get PDFAlthough literature identifies a repertoire of constructive and defensive responses to paradox, the problem of overcoming dissonance remains. While a both-and response at the individual or collective level is desirable, individuals encountering paradoxes will likely respond defensively, separating tensions into either-or poles. Insight into how individuals can work with tension created by dissonance is limited. Musical composition may have something to share. Since the Renaissance, composers have exposed listeners to constructively responding to tension through increasingly dissonant music. Arnold Schönberg’s dodecaphonic (twelve-tone) system emancipates the constraints of dissonance, reducing listeners’ resistance and developing a connoisseur’s appreciation of structural incompatibilities
Design and synthesis of aliphatic supramolecular polymers featuring amide, urethane, and urea hydrogen bonding units
Get PDFFunctionalisation of polyurethane-urea oligomers with hydrogen bonding amide end groups leads to dramatic thermal, mechanical, morphological, and rheological changes of supramolecular polyurethane elastomers. This study reports the design, synthesis and characterisation of six new aliphatic thermally stable supramolecular polyurethanes (SPUs). It was found that introduction of the amide end groups affords a polymer network that is maintained by dynamic associations within the solid state of the material. Through atomic force microscopy (AFM), the aggregation of hard segments of these phase separated SPU networks was found to be more prominent with the introduction of the amide end groups. The strong hydrogen bonding associations between the amide end groups were complemented by urea-urea and urethane-urethane interactions from the main chains to enhance the self-assembly and phase separation of SPUs and also improve the mechanical, thermal and rheological properties with respect to other SPU elastomers that feature bisamide end groups. These thermally stable phase separated SPUs also displayed remarkable re-adhesive capabilities on both glass and aluminium substrates, for example, SPU2 exhibited unique reusability after seven adhesion cycles