Erratum for article “Methodological problems in every black-box study of forensic firearm comparisons” https://doi.org/10.1093/lpr/mgae015

Reviews conducted by the National Academy of Sciences (2009) and the President’s Council of Advisors on Science and Technology (2016) concluded that the field of forensic firearm comparisons has not been demonstrated to be scientifically valid. Scientific validity requires adequately designed studies of firearm examiner performance in terms of accuracy, repeatability, and reproducibility. Researchers have performed “black-box” studies with the goal of estimating these performance measures. As statisticians with expertise in experimental design, we conducted a literature search of such studies to date and then evaluated the design and statistical analysis methods used in each study. Our conclusion is that all studies in our literature search have methodological flaws that are so grave that they render the studies invalid, that is, incapable of establishing scientific validity of the field of firearms examination. Notably, error rates among firearms examiners, both collectively and individually, remain unknown. Therefore, statements about the common origin of bullets or cartridge cases that are based on examination of “individual” characteristics do not have a scientific basis. We provide some recommendations for the design and analysis of future studies.

Five double-blind trials of the prophylactic treatment of migraine with beta-blockers were reviewed critically with regard to problem investigated, design, "blindness" of patient, side effects, statistical validity, and conclusions. The initial use of a "responder-finding" period may limit the validity of results from a subsequent double-blind crossover placebo-controlled study because it may impair "blindness". A d-propranolol versus racemic propranolol versus placebo study was reanalysed with conventional statistical methods, which showed that d-propranolol had no significant effect. In a multicentre study including 96 patients calculation of 95% confidence limits demonstrated that timolol and propranolol are equally effective in common migraine prophylaxis. Metopropolol and propranolol were apparently equally effective in 34 patients, but the calculation of confidence limits showed that a larger study is needed to confirm this conclusion. A group comparison study with three doses of nadolol and placebo lacked statistical evaluation of the results, thereby making it impossible to draw a conclusion about the efficacy of nadolol. It is concluded that there are considerable methodological problems in published papers on beta-blocker and migraine.

Following the rapid development of gene selection methods, several comparison studies have been reported for ranking methods on various datasets. In order to reduce bias in performance measures, most studies use an evaluation scheme based on cross-validation. In this paper we focus on the methodology of evaluation itself and address methodological problems using three representative algorithms on two public datasets. More specifically, the paper discusses the need of an independent test-set to reduce bias associated with cross-validation, the use of case specific considerations for generalization, as well as other measures that reflect stability and consistency of the result. Such measures reflect the influence of the actual dataset distribution on the performance of gene selection methods.

This thesis has two main aims: to give information about attitudes to painting among the French symbolist poets and critics, 1885-1895 and, from here, to examine the place of painting in the work of three of the most important poets of this period. After introductory remarks on the tradition of inter-arts comparisons in French nineteenth-century aesthetic theory and on the methodological problems raised by the study of such comparisons (together with the inadequacies of previous work on the subject for the period in question), chapter two examines Albert Aurier's definition of pictorial Symbolism in order to show that the reluctance of symbolist poets and painters alike to accept it is based upon differences in attitudes among both groups to the subject-matter of painting. These different attitudes in turn influence interpretations of pictorial form which are studied in chapter three. Particular attention is paid to those poets and critics who seek to assimilate visual values within verbal models of expression as part of a wider search for a synthesis of the arts. The thesis then goes on to study the work of three poets who apply, in their experiments with poetic language the lessons taken from a profound understanding of specific painting. Chapter four discusses Manet’s influence upon Mallarme’s poetic style through a detailed analysis of the changes made by the poet to successive versions of 'L'Apres-midi d'un faune' ; Chapter five, the influence of Seurat's divisionist technique upon the 'vers libre' of Gustave Kahn; chapter six, that of Gauguin's synthetist style upon the abstract poetic language of Alfred Jarry. Through these poets, the thesis attempts to show the extent to which pictorial reference and analogy contributed to certain fundamental developments in modern French poetry.

To examine the long-term productivity, profitability, and ecological interactions associated with whole farming systems, we established an interdisciplinary replicated comparison of a conventional and an experimental alternative crop-livestock farming system in southwest Virginia in 1988. The conventional system uses the best management practices commonly used in the mid-Atlantic region. The alternative system puts more emphasis on crop rotation, grazing and forage management, conservation tillage, cover crops, and integrated pest management. Each is managed as a year-round system, with management decisions based on the system's overall goals.The comparison is planned to run for 10 years, so that only preliminary conclusions can be drawn so far. These include the following: 1) similar total productivity can be achieved with either reduced or full use of herbicides and insecticides; 2) the need for N fertilization can be decreased using grazing management and short-rotation alfalfa; and 3) recycling of manure from cattle fed corn silage provides most nutrients needed for the following corn crop. The comparative profitability of the two systems has fluctuated among years, and it is too early to know which system is more profitable. The process of interdisciplinary systems research has increased our knowledge of total system interactions, challenged prior assumptions, and clarified the methodological problems of integrated systems research.

Despite differences in their mechanisms and outcomes, little is known about whether postsurgical changes in eating behaviours also differ by bariatric procedure. Following a systematic search, 23 studies on changes in binge eating disorder (BED) and related behaviours, bulimia nervosa and related behaviours, night eating syndrome, grazing and emotional eating after Roux-en-Y gastric bypass (RYGB), adjustable gastric banding (AGB) and vertical sleeve gastrectomy (VSG) were reviewed. Significant methodological problems and a dearth of literature regarding many behaviours and VSG were seen. Regarding BED and related behaviours, although later re-increases were noted, short to medium-term reductions after RYGB were common, and reported changes after AGB were inconsistent. Short to medium-term reductions in emotional eating, and from a few studies, short to long-term reductions in bulimic symptoms, were reported after RYGB. Reoccurrences and new occurrences of problem and disordered eating, especially BED and binge episodes, were apparent after RYGB and AGB. Further conclusions and comparisons could not be made because of limited or low-quality evidence. Long-term comparison studies of changes to problematic and disordered eating in RYGB, AGB and VSG patients are needed. It is currently unclear whether any bariatric procedure leads to long-term improvement of any problematic or disordered eating behaviours.