Replicability is not Reproducibility:\ud Nor is it Good Science

At various machine learning conferences, at various times, there have been discussions arising from the inability to replicate the experimental results published in a paper. There seems to be a wide spread view that we need to do something to address this problem, as it is essential to the advancement of our field. The most compelling argument would seem to be that reproducibility of experimental results is the hallmark of science. Therefore, given that most of us regard machine learning as a scientific discipline, being able to replicate experiments is paramount. I want to challenge this view by separating the notion of reproducibility, a generally desirable property, from replicability, its poor cousin. I claim there are important differences between the two. Reproducibility requires changes; replicability avoids them. Although reproducibility is desirable, I contend that the impoverished version, replicability, is one not worth having

Reproducible Research: a Dissenting Opinion

Reproducible Research, the de facto title of a growing movement\ud within many scientific fields, would require the code, used to\ud generate the experimental results, be published along with any\ud paper. Probably the most compelling argument for this is that it is\ud simply following good scientific practice, established over the\ud years by the greats of science. It is further claimed that\ud misconduct is causing a growing crisis of confidence in science.\ud That, without this requirement being enforced, science would\ud inevitably fall into disrepute. This viewpoint is becoming\ud ubiquitous but here I offer a dissenting opinion. I contend that\ud the consequences are somewhat overstated. Misconduct is far from\ud solely a recent phenomenon; science has succeeded despite it.\ud Further, I would argue that the problem of public trust is more to\ud do with other factors. I would also contend that the effort\ud necessary to meet the movement's aims, and the general attitude it\ud engenders, would not serve any of the research disciplines well

Webs in multiparton scattering using the replica trick

Soft gluon exponentiation in non-abelian gauge theories can be described in terms of webs. So far this description has been restricted to amplitudes with two hard partons, where webs were defined as the colour-connected subset of diagrams. Here we generalise the concept of webs to the multi-leg case, where the hard interaction involves non-trivial colour flow. Using the replica trick from statistical physics we solve the combinatorial problem of non-abelian exponentiation to all orders. In particular, we derive an algorithm for computing the colour factor associated with any given diagram in the exponent. The emerging result is exponentiation of a sum of webs, where each web is a linear combination of a subset of diagrams that are mutually related by permuting the eikonal gluon attachments to each hard parton. These linear combinations are responsible for partial cancellation of subdivergences, conforming with the renormalization of a multi-leg eikonal vertex. We also discuss the generalisation of exponentiation properties to beyond the eikonal approximatio

Brief intervention to prevent hazardous drinking in young people aged 14–15 in a high school setting (SIPS JR-HIGH): study protocol for a randomized controlled trial

Background: Whilst the overall proportion of young people drinking alcohol in the United Kingdom has decreased in recent years, those who do drink appear to drink a larger amount, and more frequently. Early and heavy drinking by younger adolescents is a significant public health problem linked to intellectual impairment, increased risk of injuries, mental health issues, unprotected or regretted sexual experience, violence, and sometimes accidental death, which leads to high social and economic costs. This feasibility pilot trial aims to explore the feasibility of delivering brief alcohol intervention in a school setting with adolescents aged 14 and 15 and to examine the acceptability of study measures to school staff, young people and parents. Methods and design: Seven schools across one geographical area in the North East of England will be recruited. Schools will be randomly allocated to one of three conditions: provision of an advice leaflet (control condition, n= 2 schools); a 30-minute brief interactive session, which combines structured advice and motivational interviewing techniques delivered by the school learning mentor (level 1 condition, n= 2 schools); and a 60-minute session involving family members delivered by the school learning mentor (level 2 condition, n= 3 schools). Participants will be year 10 school pupils (aged 14 and 15) who screen positively on a single alcohol screening question and who consent to take part in the trial. Year 10 pupils in all seven schools will be followed up at 6 and 12 months. Secondary outcome measures include the ten-question Alcohol-Use Disorders Identification Test. The EQ-5D-Y and a modified short service use questionnaire will inform the health and social resource costs for any future economic evaluation. Young people recruited into the trial will also complete a 28-day timeline follow back questionnaire at 12-month follow-up. A qualitative evaluation (with young people, school staff, learning mentors, and parents) will examine facilitators and barriers to the use of screening and brief intervention approaches in the school setting in this age group

Maternal and neonatal outcomes after caesarean delivery in the African Surgical Outcomes Study: a 7-day prospective observational cohort study.

BACKGROUND: Maternal and neonatal mortality is high in Africa, but few large, prospective studies have been done to investigate the risk factors associated with these poor maternal and neonatal outcomes. METHODS: A 7-day, international, prospective, observational cohort study was done in patients having caesarean delivery in 183 hospitals across 22 countries in Africa. The inclusion criteria were all consecutive patients (aged ≥18 years) admitted to participating centres having elective and non-elective caesarean delivery during the 7-day study cohort period. To ensure a representative sample, each hospital had to provide data for 90% of the eligible patients during the recruitment week. The primary outcome was in-hospital maternal mortality and complications, which were assessed by local investigators. The study was registered on the South African National Health Research Database, number KZ_2015RP7_22, and on ClinicalTrials.gov, number NCT03044899. FINDINGS: Between February, 2016, and May, 2016, 3792 patients were recruited from hospitals across Africa. 3685 were included in the postoperative complications analysis (107 missing data) and 3684 were included in the maternal mortality analysis (108 missing data). These hospitals had a combined number of specialist surgeons, obstetricians, and anaesthetists totalling 0·7 per 100 000 population (IQR 0·2-2·0). Maternal mortality was 20 (0·5%) of 3684 patients (95% CI 0·3-0·8). Complications occurred in 633 (17·4%) of 3636 mothers (16·2-18·6), which were predominantly severe intraoperative and postoperative bleeding (136 [3·8%] of 3612 mothers). Maternal mortality was independently associated with a preoperative presentation of placenta praevia, placental abruption, ruptured uterus, antepartum haemorrhage (odds ratio 4·47 [95% CI 1·46-13·65]), and perioperative severe obstetric haemorrhage (5·87 [1·99-17·34]) or anaesthesia complications (11·47 (1·20-109·20]). Neonatal mortality was 153 (4·4%) of 3506 infants (95% CI 3·7-5·0). INTERPRETATION: Maternal mortality after caesarean delivery in Africa is 50 times higher than that of high-income countries and is driven by peripartum haemorrhage and anaesthesia complications. Neonatal mortality is double the global average. Early identification and appropriate management of mothers at risk of peripartum haemorrhage might improve maternal and neonatal outcomes in Africa. FUNDING: Medical Research Council of South Africa.Medical Research Council of South Africa