A flexible mixed model for age-dependent performance: application to golf

We present a new mixed linear model for the relationship between age and performance. The model allows for random effects at the nodes of a barycentric interpolation, such that performance evolves with age in a non-prescriptive way. We use the model to investigate the effects of age on performance in golf and find that performance peaks in the 30s and then declines after that. We disaggregate performance into its constituent components and find that driving, which tends to require power and speed, deteriorates consistently from the early 20s, whilst putting, which requires touch and finesse, remains strong until the late 40s. Our model can be used in other settings, and requires only that measures of performance exist

Plus-Minus Player Ratings for Soccer

The paper presents plus–minus ratings for use in association football (soccer). We first describe the general plus–minus methodology as used in basketball and ice-hockey and then adapt it for use in soccer. The usual goal-differential plus–minus is considered before two new variations are proposed. For the first variation, we present a methodology to calculate an expected goals plus–minus rating. The second variation makes use of in-play probabilities of match outcome to evaluate an expected points plus–minus rating. We use the ratings to examine who are the best players in European football, and demonstrate how the players’ ratings evolve over time. Finally, we shed light on the debate regarding which is the strongest league. The model suggests the English Premier League is the strongest, with the German Bundesliga a close runner-up

Homozygosity for a missense mutation in the 67 kDa isoform of glutamate decarboxylase in a family with autosomal recessive spastic cerebral palsy: parallels with Stiff-Person Syndrome and other movement disorders

Background Cerebral palsy (CP) is an heterogeneous group of neurological disorders of movement and/or posture, with an estimated incidence of 1 in 1000 live births. Non-progressive forms of symmetrical, spastic CP have been identified, which show a Mendelian autosomal recessive pattern of inheritance. We recently described the mapping of a recessive spastic CP locus to a 5 cM chromosomal region located at 2q24-31.1, in rare consanguineous families. Methods Here we present data that refine this locus to a 0.5 cM region, flanked by the microsatellite markers D2S2345 and D2S326. The minimal region contains the candidate gene GAD1, which encodes a glutamate decarboxylase isoform (GAD67), involved in conversion of the amino acid and excitatory neurotransmitter glutamate to the inhibitory neurotransmitter γ-aminobutyric acid (GABA). Results A novel amino acid mis-sense mutation in GAD67 was detected, which segregated with CP in affected individuals. Conclusions This result is interesting because auto-antibodies to GAD67 and the more widely studied GAD65 homologue encoded by the GAD2 gene, are described in patients with Stiff-Person Syndrome (SPS), epilepsy, cerebellar ataxia and Batten disease. Further investigation seems merited of the possibility that variation in the GAD1 sequence, potentially affecting glutamate/GABA ratios, may underlie this form of spastic CP, given the presence of anti-GAD antibodies in SPS and the recognised excitotoxicity of glutamate in various contexts

Operational Research: Methods and Applications

Throughout its history, Operational Research has evolved to include a variety of methods, models and algorithms that have been applied to a diverse and wide range of contexts. This encyclopedic article consists of two main sections: methods and applications. The first aims to summarise the up-to-date knowledge and provide an overview of the state-of-the-art methods and key developments in the various subdomains of the field. The second offers a wide-ranging list of areas where Operational Research has been applied. The article is meant to be read in a nonlinear fashion. It should be used as a point of reference or first-port-of-call for a diverse pool of readers: academics, researchers, students, and practitioners. The entries within the methods and applications sections are presented in alphabetical order. The authors dedicate this paper to the 2023 Turkey/Syria earthquake victims. We sincerely hope that advances in OR will play a role towards minimising the pain and suffering caused by this and future catastrophes

Transmission of Problem Gambling Between Adjacent Generations

We investigate the extent to which gambling problems at age 20 are linked to parental gambling behaviour during childhood, employing data from a longitudinal study (ALSPAC) which has followed parents and children from Avon, England since pregnancy. 1058 children completed a problem gambling screen at age 20. When those children had been age 6, each of their parents was asked about their own gambling. We used regression to estimate the effect of parental gambling behaviour at child age 6 on the child’s problem gambling risk at age 20. Parental gambling participation at child age 6 was not a predictor of offspring problem gambling; but problem gambling by parents was a predictor of offspring problem gambling. However, this latter result was found only cross-gender (fathers’ behaviour influencing daughters and mothers’ behaviour influencing sons). This pattern was robust to models including measures of parental education and variables capturing family attitudes to health choices and the degree of domestic harmony. The sample illustrates high problem gambling prevalence amongst young adults. Although there is transmission of ‘problem gambling’ between generations, it appears to happen only cross-gender. This limits the importance of parental problem gambling as a source of the high prevalence because relatively few mothers exhibit problem gambling and risks to daughters from fathers are in the context of initially low baseline risks. Preventative policies might therefore be more appropriately targeted at young adults rather than rely on influencing parental gambling behaviour earlier in the child’s life. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s10899-020-09977-8) contains supplementary material, which is available to authorized users

Evaluating the impact of the uplift of stakes and prizes on B1 gaming machines in casinos

No abstract available