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Shuffling a deck of cards is normally used for randomization. An imperfect shuffle would not produce the desired randomization, since there would be residual correlation with the original order. On the other hand, from the classical card magic literature it is known that eight successive perfect riffle shuffles returns the deck to the original order. The question addressed here is whether this observation is in fact unusual and surprising. Although a general closed‐form analytical solution does not appear to be possible, a simple program could be written to determine deck sizes and numbers of shuffles for which eventual reordering occurs. This computational approach correctly predicts the original observation of eight shuffles for a deck of 52 cards; in fact if the trivial solutions of integral multiples of eight shuffles are discarded, eight shuffles appears to be the unique solution for a 52 card deck.

The purpose of this paper is to present the results of a pilot trial, investigating the accessibility provided by a tablet computer (Apple iPad) to individuals with visual impairment. The study was designed around an N-of-1 randomised controlled trial (RCT), which was replicated for 12 participants. It served as an opportunity to evaluate the use N-of-1 trials in studies involving people who are visually impaired.

The study centred round an N-of-1 RCT, comparing the accessibility provided by control equipment (Windows computer) against the intervention equipment (Apple iPad). Twelve participants conducted six tests on the equipment as per randomisation, followed by a quantitative-based evaluation and short interviews.

One-sided individual randomisation tests showed a significant result for overall satisfaction in favour of the tablet at the 0.05 significance level for seven of the participants. Participants identified several strengths of the iPad in helping a partially sighted user in accessing the internet: inbuilt zoom and magnification options; increased control as a result of the touch screen; and accessibility tools being built into the operating system. The main limitation suggested was the way the zoom function operates by enlarging the onscreen keyboard. This caused difficulties for those with more severe visual impairments using this function in inputting text.

There has been limited research to substantiate positive reviews of the tablet computer for low-vision users. The results of this pilot study gives evidence in support of these potential benefits, and demonstrates the importance of a more thorough investigation.

This paper aims to evaluate the use of Mendelian randomization (MR) analyses for judging the effects of alcohol consumption on the risk of coronary heart disease (CHD).

This paper presents a review of methodology for MR and describes its early application to judging health effects of alcohol, current uses and a recommended approach of combining MR results with those from observational and experimental studies.

Early applications of MR to health effects of alcohol consumption were inadequate for providing unbiased results, but newer attempts using polygenic scores show promise. It is important to combine data from MR analyses with those from observational and experimental studies to obtain an unbiased and scientifically sound estimate of alcohol’s effects on health.

Giving advice to the public regarding alcohol consumption must be based on accurate, unbiased scientific data; this paper describes attempts to use MR for achieving this goal.

Given that light-to-moderate alcohol intake is associated with a lower risk of CHD, type II diabetes mellitus and total mortality, it is important to be able to evaluate both the benefits and harms from alcohol before giving advice regarding drinking.

This is part of a group of three papers dealing with the potential health benefits and harms associated with alcohol consumption.

The application of far-infrared energy to skin is expected to lead to vasodilatation of the skin surface, consequently warming the skin, and promoting sleep induction. The purpose of this paper was to test whether bedsheets impregnated with bioceramic far-infrared technology would improve the perception of sleep in a sample of healthy adults.

Twenty-nine adults consented to participate, randomizing 17 to the far-infrared bedsheets and 12 to the control bedsheets. Two of the control participants dropped out prior to randomization and prior to completing any assessments and therefore are excluded from the analyses. After baseline assessment, participants slept on their randomly assigned sheets for five weeks, followed by a one week “wash out”. Insomnia symptoms were assessed with the Insomnia Severity Index, depression symptoms with the Patient Health Questionnaire, “vigor” and “fatigue” with the Profile of Mood States, and napping behavior with daily sleep diaries.

During the period of randomization, the participants on the far-infrared sheets reported fewer insomnia symptoms and less napping. This advantage was lost during the wash out period.

Far-infrared technology produces benefits on reported sleep in healthy normal adults.

Single-party regimes increasingly use Subnational Performance Assessments (SPAs) – rankings of provinces and districts – to improve governance outcomes. SPAs assemble and publicize information on local government performance to facilitate monitoring and generate competition among officials. However, the evidence are sparse on their effects in this context. The authors argue that built-in incentive structures in centralized single-party regimes distort the positive impact of SPAs.

The staggered rollout of the Vietnam Provincial Governance and Public Administration Performance Index (PAPI) created a natural experiment. Due to 2010 budget constraints, the first iteration of the PAPI survey covered only 30 of Vietnam’s 63 provinces before covering all in 2011. The PAPI team used matching procedures to identify a statistical twin for each province before randomly selecting one from each pair. The authors use randomization inference to compare the outcomes of these control and treatment groups in 2011.

Exposure to PAPI helped improve almost all aspects of governance; however, significant evidence of prioritization bias exist. The positive effects only persisted for the dimension of administrative procedures, which was the one area of governance that was prioritized by the central government at the time. Other dimensions only registered short-term effects.

Our study provides an examination of the impact of SPAs in a single-party regime context. In addition, the authors leverage the natural experiment to identify information effects causally. The authors also look past short-term effects to compare outcomes for five years after the treatment occurred.

The purpose of this study is to present a systematic methodological review of the application of field experiments in the domain of marketing research. By performing this study, the authors seek to offer necessary advice and suggestions to marketing scholars interested in the application of field experiments and to promote the adoption of field experiments as a preferred methodological choice among scholars in this domain.

A total of 315 field experiments published in the ten leading marketing journals in the past five decades were analyzed in this systematic methodological review. This study examines various aspects of field experiments, including the research profile of existing research, different trends and topics related to field experiments, choice of research questions, methods of observations, unobtrusive data collection, types of interventions and outcome variables.

This study identified various trends and topics, categories of manipulations, types of limitations and important considerations in designing field experiments and offered necessary advice on the future of field experiments in marketing research.

This study provides a complete roadmap for future marketing scholars to adopt field studies in their research plans. The systematic summary of limitations and the checklist will be helpful for the researchers to design and execute field studies more effectively and efficiently.

This review study offers a complete roadmap for marketing scholars who are interested in adopting field experiments in their research projects. The discussion of trends and topics, manipulations, limitations, design considerations and checklist items for field experiments offers relevant insights to marketing scholars and may help them design and execute field experiments more effectively and efficiently.

To the best of the authors’ knowledge, this study is the first of its kind to provide a comprehensive methodological review of field experiments published in leading marketing journals throughout the past five decades. This study makes novel and unique contributions to both theory and literature on field experiments in the marketing discipline.

The need for randomised controlled trials (RCTs) to support evidence‐based services to improve outcomes for children is increasingly recognised by researchers and policy‐makers. However, this brings a pressing requirement to build research capacity for conducting RCTs and to address the concerns of practitioners who may be suspicious about the method. This article reviews a variety of texts on the subject, ranging from analyses of the historical and political context of RCTs, to concise introductions of the key methodological and practical issues, to more in‐depth discussions of complex designs and statistics. The article seeks to help readers navigate these resources by focusing on seven questions that seem particularly salient for those considering whether and how to commission, undertake, participate in or use results from RCTs.

Meat consumption has a variety of implications in society. While various types of meat-restricted diets exist to address this, not enough is known about how the average meat consumer views different avenues to lessening their intake. In response, this study aims to assess US omnivores’ impressions of three meat-restricted diets.

An online survey was administered to a cross-sectional, census-balanced sample from Nielsen of 30,000+ US adults. Omnivores (N = 928) were randomized into one of the three conditions where they were asked about their perceptions of a vegetarian diet, a reduced-meat diet or a chicken-free diet as individuals not currently following that dietary pattern.

The findings showed that omnivores had a more favorable perception of a reduced-meat diet on a greater number of study variables as compared to the vegetarian or chicken-free diets. The research also demonstrated that a majority of omnivores were in the precontemplation stage of cognitive change, suggesting that most American omnivores are not actively demonstrating a readiness to alter their meat consumption in the ways presented.

This research is the first to examine the comparative trends around these three diets among omnivores. It also speaks to how the desirability of meat restriction varies by type of approach, i.e. elimination or reduction, and if the latter, what type. The findings may be of relevance for efforts to reduce global meat consumption for ethical, health, or environmental reasons.

By using the central limit theorem, it is possible to consider the Fourier’s transform of a stochastic process with independent increments as a Gaussian random variable of which the mathematical expectation and the variance are respectively integrals of the mean and the variance of this process. One can then use this result to analyze the statistical properties of linear feedback systems in the frequency domain, that is to say in terms of transfer functions. The advantage of this approach is that one can deal with linear systems subject to squared white noises, in a very simple manner.

While the main purpose of reporting – e.g. reporting for taxes – is to gauge the economic state of a company, the fact that reporting is done at pre-determined dates distorts the reporting results. For example, to create a larger impression of their productivity, companies fire temporary workers before the reporting date and re-hire then right away. The purpose of this study is to decide how to avoid such distortion.

This study aims to come up with a solution which is applicable for all possible reasonable optimality criteria. Thus, a general formalism for describing and analyzing all such criteria is used.

This study shows that most distortion problems will disappear if the fixed pre-determined reporting dates are replaced with individualized random reporting dates. This study also shows that for all reasonable optimality criteria, the optimal way to assign reporting dates is to do it uniformly.

This study shows that for all reasonable optimality criteria, the optimal way to assign reporting dates is to do it uniformly.

It is found that the individualized random tax reporting dates would be beneficial for economy.

It is found that the individualized random tax reporting dates would be beneficial for society as a whole.

This study proposes a new idea of replacing the fixed pre-determining reporting dates with randomized ones. On the informal level, this idea may have been proposed earlier, but what is completely new is our analysis of which randomization of reporting dates is the best for economy: it turns out that under all reasonable optimality criteria, uniform randomization works the best.