The CONEstrip algorithm

Uncertainty models such as sets of desirable gambles and (conditional) lower previsions can be represented as convex cones. Checking the consistency of and drawing inferences from such models requires solving feasibility and optimization problems. We consider finitely generated such models. For closed cones, we can use linear programming; for conditional lower prevision-based cones, there is an efficient algorithm using an iteration of linear programs. We present an efficient algorithm for general cones that also uses an iteration of linear programs

Sets of Priors Reflecting Prior-Data Conflict and Agreement

In Bayesian statistics, the choice of prior distribution is often debatable, especially if prior knowledge is limited or data are scarce. In imprecise probability, sets of priors are used to accurately model and reflect prior knowledge. This has the advantage that prior-data conflict sensitivity can be modelled: Ranges of posterior inferences should be larger when prior and data are in conflict. We propose a new method for generating prior sets which, in addition to prior-data conflict sensitivity, allows to reflect strong prior-data agreement by decreased posterior imprecision.Comment: 12 pages, 6 figures, In: Paulo Joao Carvalho et al. (eds.), IPMU 2016: Proceedings of the 16th International Conference on Information Processing and Management of Uncertainty in Knowledge-Based Systems, Eindhoven, The Netherland

Factorisation properties of the strong product

We investigate a number of factorisation conditions in the frame- work of sets of probability measures, or coherent lower previsions, with finite referential spaces. We show that the so-called strong product constitutes one way to combine a number of marginal coherent lower previsions into an independent joint lower prevision, and we prove that under some conditions it is the only independent product that satisfies the factorisation conditions

Productivity and N-fixation of legume-cereal intercrops and their monocrop counterparts in organic cropping systems

Non-Peer ReviewedIn recent years, western Canada has seen considerable growth in organic production. This is due to heightened environmental awareness, reduced input costs, diversification of market opportunities, and food safety aspects. On the prairies, organic production generally includes the use of annual green manure (GrM) crops, which are plowed under to add nutrients to the soil. However, in a GrM plow-down year, farmers face loss of income. One alternative to growing a traditional GrM could be growing legumes alone or intercropping them with cereals and managing them as green feed forage (GF) for use on-farm or for sale to local livestock producers without compromising soil fertility levels. Intercropping legumes with cereals may be a novel approach to problems of nitrogen (N) supply as the legume may provide N to the current and subsequent crops. It was hypothesized that by intercropping the legume with a cereal, the inorganic N supply would be reduced to levels where N fixation in the legume would be stimulated. This study (i) compared yield in monoculture legume with legume-cereal intercrops (ii) investigated whether increasing cereal density stimulated the legume to fix more N (iii) Compared yield of a cereal grown after the GrM and GF crop treatments. The study included mixtures of feed pea (Pisum sativum cv 40-10 silage pea), oat (Avena sativa L.cv AC Morgan), and triticale (X Triticosecale Wittmack cv Pika). The experiment consisted of 16 treatments and 4 replicates in which feed pea, oat, and triticale were grown alone or in combination and managed as GrM or GF. Wheat and fallow (tillage) served as cropped and uncropped controls respectively. The intercropped oat was seeded at three densities (50, 100, and 150 plants m-2). In the second year, wheat was seeded in all plots. In this paper, biomass, total nitrogen (N), and nitrogen derived from the atmosphere (Ndfa) of treatments and subsequent yields of wheat grown after the treatments at the Delisle site are discussed. Results show that the oat (4238 kg ha-1) and fieldpea + oat 2 (3630 kg ha-1) treatments had the highest biomass whereas the triticale (1357 kg ha-1) treatment had the lowest. Among the intercrops, only the fieldpea + oat 2 treatments had higher total nitrogen (91.61 kg ha-1) than their monocultures, with the oat treatment being the least (45 kg ha-1). The highest %Ndfa was achieved at the highest intercropped cereal density of fieldpea + oat 1 (84%). Wheat grain yield were consistently higher following GrM treatments whereas biomass removal significantly compromised subsequent wheat yields in the GF treatments

Clinicopathological determinants of an elevated systemic inflammatory response following elective potentially curative resection for colorectal cancer

Introduction: The postoperative systemic inflammatory response (SIR) is related to both long- and short-term outcomes following surgery for colorectal cancer. However, it is not clear which clinicopathological factors are associated with the magnitude of the postoperative SIR. The present study was designed to determine the clinicopathological determinants of the postoperative systemic inflammatory response following colorectal cancer resection. Methods: Patients with a histologically proven diagnosis of colorectal cancer who underwent elective, potentially curative resection during a period from 1999 to 2013 were included in the study (n = 752). Clinicopathological data and the postoperative SIR, as evidenced by postoperative Glasgow Prognostic Score (poGPS), were recorded in a prospectively maintained database. Results: The majority of patients were aged 65 years or older, male, were overweight or obese, and had an open resection. After adjustment for year of operation, a high day 3 poGPS was independently associated with American Society of Anesthesiologists (ASA) grade (hazard ratio [HR] 1.96; confidence interval [CI] 1.25–3.09; p = 0.003), body mass index (BMI) (HR 1.60; CI 1.07–2.38; p = 0.001), mGPS (HR 2.03; CI 1.35–3.03; p = 0.001), and tumour site (HR 2.99; CI 1.56–5.71; p < 0.001). After adjustment for year of operation, a high day 4 poGPS was independently associated with ASA grade (HR 1.65; CI 1.06–2.57; p = 0.028), mGPS (HR 1.81; CI 1.22–2.68; p = 0.003), NLR (HR 0.50; CI 0.26–0.95; p = 0.034), and tumour site (HR 2.90; CI 1.49–5.65; p = 0.002). Conclusions: ASA grade, BMI, mGPS, and tumour site were consistently associated with the magnitude of the postoperative systemic inflammatory response, evidenced by a high poGPS on days 3 and 4, in patients undergoing elective potentially curative resection for colorectal cancer

Value co-creation in the animal healthcare sector

Domesticated animals form an important part of modern life, fulfilling roles as household companions, working animals or food producing livestock. Regardless of the position they realise within contemporary society,their day to day care is now complex and involves a range of animal healthcare practitioners in addition to the veterinary professional, termed paraprofessionals. The discerning nature of the modern client in combination with the developing roles of professionals within the sector has transformed market dynamics and highlighted the need for reflection on measures of service quality and its provision. This paper presents a conceptualisation of value co- creation within animal healthcare based on an analysis of sector stakeholders’ service experiences. Interviews with service providers and clients provide data for content analysis and highlight the dimensions of communication and integrated care as important components of service provision. Exploratory factor analysis of questionnaire data (n=271) following surveying of veterinarians and paraprofessionals,loaded onto seven latent factors, with strong dimensions of trust and communication identified. Disparity between veterinarian and client opinion was of interest and is worthy of further investigation,but results obtained support the application of value co-creation models to develop service quality within the UK animal healthcare sector

Computable randomness is about more than probabilities

We introduce a notion of computable randomness for infinite sequences that generalises the classical version in two important ways. First, our definition of computable randomness is associated with imprecise probability models, in the sense that we consider lower expectations (or sets of probabilities) instead of classical 'precise' probabilities. Secondly, instead of binary sequences, we consider sequences whose elements take values in some finite sample space. Interestingly, we find that every sequence is computably random with respect to at least one lower expectation, and that lower expectations that are more informative have fewer computably random sequences. This leads to the intriguing question whether every sequence is computably random with respect to a unique most informative lower expectation. We study this question in some detail and provide a partial answer

Barriers to hospital and tuberculosis programme collaboration in China: context matters

Background: In many developing countries, programmes for ‘diseases of social importance’, such as tuberculosis (TB), have traditionally been organised as vertical services. In most of China, general hospitals are required to report and refer suspected TB cases to the TB programme for standardised diagnosis and treatment. General hospitals are the major contacts of health services for the TB patients. Despite the implementation of public–public/private mix, directly observed treatment, short-course, TB reporting and referral still remain a challenge. Objective: This study aims to identify barriers to the collaboration between the TB programme and general hospitals in China. Design: This is a qualitative study conducted in two purposefully selected counties in China: one in Zhejiang, a more affluent eastern province, and another in Guangxi, a poorer southwest province. Sixteen in-depth interviews were conducted and triangulated with document review and field notes. An open systems perspective, which views organisations as social systems, was adopted. Results: The most perceived problem appeared to be untimely reporting and referral associated with non-standardised prescriptions and hospitalisation by the general hospitals. These problems could be due to the financial incentives of the general hospitals, poor supervision from the TB programme to general hospitals, and lack of technical support from the TB programme to the general hospitals. However, contextual factors, such as different funding natures of different organisations, the prevalent medical and relationship cultures, and limited TB funding, could constrain the processes of collaboration between the TB programme and the general hospitals. Conclusions: The challenges in the TB programme and general hospital collaboration are rooted in the context. Improving collaboration should reduce the potential mistrust of the two organisations by aligning their interests, improving training, and improving supervision of TB control in the hospitals. In particular, effective regulatory mechanisms are crucial to alleviate the negative impact of the contextual factors and ensure smooth collaboration