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Precooling and sulfur dioxide fumigation were proved as effective methods for the preservation of longan (Dimocarpus longan Lour.) fruits. However, inadequate precooling and sulfur dioxide fumigation resulted in unexpected losses and short shelf life. A L9(34) orthogonal test was conducted to screen out ideal dosage of sodium metabisulfite (factor A), precooling method (factor B), and precooling duration (factor C) to improve the storability of longan fruit stored for 48 hr at room temperature (RT) (25℃). The overall qualities of all of the treated longan fruits after a 48‐hr storage (OQST) and during the 5‐day shelf at 25℃ (OQSF) were better than those of the control fruits. The treated fruits showed brighter fresh color (higher L*, b*, C*, and h° values but lower a* value), higher flavonoid, and chlorophyll contents. Moreover, the SO2 residue was concentrated in pericarp but little in aril for any of the 12 treatments. The multivariate variance analysis showed that factor A was dominant to determine both of the OQST and OQSF, while factor B affected the OQST, and factor C affected the OQSF. In total, "0.22% sodium metabisulfite + 4 hr precooling + uncovered precooling" was considered to be an ideal treatment. These results would contribute to improving longan postharvest preservation technology. [ABSTRACT FROM AUTHOR]

There are many benefits of breastfeeding to women and their infants but meeting the recommended 6 months of exclusive breastfeeding is likely to be more challenging for women with severe mental illness (SMI). This is the first systematic review that aims to examine evidence of (a) infant feeding outcomes in women with SMI and the factors associated with this, (b) the experiences of infant feeding and infant feeding support for women with SMI, (c) interventions for supporting infant feeding among these women and (d) health care professionals' attitudes toward supporting infant feeding in women with SMI. Mixed methods systematic review was carried out using the principles of Joanna Briggs Institute's (JBI) 'convergent integrated' methodology. CINAHL, PsycINFO, Medline and MIDIRS were used to search literature between 1994 and 2022. The quality of selected articles was assessed using JBI critical appraisal tools and thematic synthesis was undertaken to obtain findings. Eighteen papers were included in the final review. Women with SMI were less likely to initiate and continue breastfeeding than women without SMI. Several challenges with breastfeeding were highlighted, and while these were often linked to women's mental health difficulties, inconsistent advice from health care professionals and poor support with breastfeeding further compounded these challenges. This review highlights that policy and practice need to take into account the individual challenges women with SMI face when planning, initiating and maintaining breastfeeding. Education and training for health care professionals are needed to enable them to provide tailored infant feeding support to women with SMI, which reflects their individual needs. Key messages: Women with severe mental illness (SMI) are less likely to initiate and maintain breastfeeding compared to women without SMI.Challenges were identified among women with SMI including poor professional support with infant feeding.Education and training are required for health care professionals to individualise infant feeding support for women with SMI and should include information regarding medication and optimising sleep while breastfeeding.No evidence of effective interventions to support breastfeeding in women with SMI were identified and there was limited evidence of women's experiences of infant feeding.Further research is required with larger sample sizes and clearly defined measures of infant feeding outcomes. [ABSTRACT FROM AUTHOR]

The article presents a response to the paper "Orthogonal Frontiers and Alternative Mean-Variance Efficiency Tests," by Bruce N. Lehmann. The author discusses some difficulties associated with the approach outlined in the original article, such as using unknown betas. The author highlights the main contribution of the paper, the introduction of an alternative procedure allowing researchers not to be restricted by the number of time-series observations and to use returns on many individual assets instead of forming portfolios.

The article discusses the pattern in vegetation, in which the peaks in the graph of mean square against block size are interpreted. To analyze the peaks in the graph, a logarithmic transformation to both the variance and the spacing is applied, and fitted a polynomial regression of log-variance on log-spacing. The apparent fit by linear regressions results from failure to allow for the occurence of overall trends in representation of species, the rising curve to be expected for random distribution, and the application of logarithmic transformation to the variance data.

This paper investigates options market reaction to changes in the instantaneous variance of the underlying asset. There are three main findings. First, options market investors underreact to individual daily changes in instantaneous variance. Second, these same investors overreact to periods of mostly increasing or mostly decreasing daily changes in instantaneous variance. Third, they tend to underreact (overreact) to current daily changes in instantaneous variance that are preceded mostly by daily changes of the opposite (same) sign. The third finding can reconcile the first two and is also consistent with well-established cognitive biases. [ABSTRACT FROM AUTHOR]

Polymers are used in various industrial applications due to their ease of production, light weight, and ductility. Fillers such as clays are added to polymers to improve a range of factors such as material processing, thermal properties, fire retardance and cost. However, adding clays may negatively impact the mechanical performance of the composite. In addition, manufacturing parameters, for example, number of extrusions, press time, and so forth may also have an influence on the resulting composite system. This study performs a statistical analysis on a set of previously obtained experimental results, which investigated the influence of various manufacturing, material, and testing parameters on the composite mechanical properties. Exploratory data and statistical analysis techniques are applied to the historical tensile test data to gain insight into the influence on mechanical properties as well as the relationships and interactions between the parameters. Specifically, it is shown that clay loading does not have a statistically significant effect on the composite mechanical properties, which is contrary to literature. Another surprising result is the poor performance of the clay that is compatible with high‐density polyethylene compared to the clay that is compatible with poly vinyl chloride. The contribution of this paper is to demonstrate the usefulness of applying statistical analysis on a large volume of data to understand the diverse correlations between the different variables. [ABSTRACT FROM AUTHOR]

Aim: The aim of the study was to investigate the incidence of sleep disturbance and its relationship with anxiety and depression symptoms, social support and hope in breast cancer patients in China during chemotherapy. Design: A single‐centre cross‐sectional study. Methods: A total of 329 breast cancer patients were selected via convenience sampling method before they began chemotherapy (n = 115), before the 5th week of chemotherapy (n = 117) or 1 month after chemotherapy ended (n = 97) and administered paper‐and‐pencil questionnaires to evaluate sleep quality, depression and anxiety symptoms, social support and hope. Risk factors significantly associated with sleep disturbance during bivariate were incorporated in the multivariate analysis. Bivariate analyses showed that age, menopausal status, depression and anxiety symptoms, emotional/informational support, tangible support, affectionate support, positive social interaction and total support were predictors of sleep disturbance. Results: Sleep disturbance was prevalent in breast cancer patients before (27.0%), during (32.5%) and after (39.2%) chemotherapy, with 37.4%, 41.9% and 52.6% of participants, respectively, reporting sleeping below the recommended 7 h. Only 8.6%–15.5% of patients reported taking sedative‐hypnotic drugs during the chemotherapy. Multivariate analyses found that participants reporting clinically significant anxiety (HADS > 8) were 3.5 times more likely to report sleep disturbance (PSQI > 8) than participants without clinically significant anxiety, and each increment in emotional/informational support was associated with a 9.04% reduced risk of sleep disturbance. Moreover, age was an independent predictor of sleep disturbance during multivariate modelling. [ABSTRACT FROM AUTHOR]

This article updates the guidance published in 2015 for authors submitting papers to British Journal of Pharmacology (Curtis et al., 2015) and is intended to provide the rubric for peer review. Thus, it is directed towards authors, reviewers and editors. Explanations for many of the requirements were outlined previously and are not restated here. The new guidelines are intended to replace those published previously. The guidelines have been simplified for ease of understanding by authors, to make it more straightforward for peer reviewers to check compliance and to facilitate the curation of the journal's efforts to improve standards. [ABSTRACT FROM AUTHOR]

The paper presents a longitudinal exploration of identification with teams and multiteam systems (MTSs) in an organizational context that started using MTSs. Data were collected in five waves during the first 2 years in which the organization started the implementation of MTSs in order to aggregate teams in value streams as organizational units. The results show that there is a clear and distinct gap between team and MTS identification. This gap is greater in larger MTSs than smaller MTSs. This gap decreases in time mostly due to a rise in MTS identification in combination with a stable team identification across time. Additionally, our research showed that MTS identification is hindered when negative relations are present in the MTS. Finally, we show that identification with the team fosters innovative team performance and the identification with MTS moderates this positive association in a compensatory manner. The findings show important implications for the management of MTSs in modern organizations. [ABSTRACT FROM AUTHOR]

Slot die coating is a common method of manufacturing electrodes for lithium‐ion batteries. In this paper, a multi‐objective optimization research on the geometry of dual‐cavity die is investigated based on the numerical simulation of lithium battery anode slurry flow combined with the surface response optimization method. First, we use the Plackett–Burman test method to screen the geometric parameters significantly affecting the optimization objective. Then, based on the Box–Behnken response surface analysis method, we determine the optimal combination of parameters. The results show that the inner cavity radius and slot gap are the main structural variables affecting exit‐velocity uniformity and die deformation. The slot gap and slot length mainly affect the inlet pressure. The coefficient of deviation of exit velocity uniformity and average inlet pressure of the optimized die structure decreased by 51.3% and 7.6%, respectively. This research provides theoretical guidance for the design of slot coating dies. Highlights: Screening significant geometric parameters using Plackett–Burman test methodology.Box–Behnken response surface analysis to determine optimal parameters.Velocity uniformity and inlet pressure increased by 51.3% and 7.6%, respectively. [ABSTRACT FROM AUTHOR]

The article offers information on the research conducted by the authors related to visual categorization of the arch index (AI), a method of measuring foot posture in older people. It states that develop and evaluate a simple visual tool for foot posture assessment based on the AI that could be used in clinical and research settings It highlights that foot posture is considered to be an important component of musculoskeletal assessment in clinical practice and research. It mentions that variations in foot posture have been found to influence lower limb gait kinematics, muscle activity, balance and functional ability and predisposition to overuse injury.

In this paper, we implement a methodology to identify and measure premia in the pricing of forward foreign exchange that involves application of signal-extraction techniques from the engineering literature. Diagnostic tests indicate that these methods are quite successful in capturing the essence of the time-series properties of premium terms. The estimated premium models indicate that premia show a certain degree of persistance over time and that more than half the variance in the forecast error that results from the use of current forward rates as predictors of future spot rates is accounted for by variation in premium terms. The methodology can be applied straight-forwardly to the measurement of unobservables in other financial markets. [ABSTRACT FROM AUTHOR]

The Arbitrage Pricing Theory (APT) has been proposed as an alternative to the mean-variance Capital Asset Pricing Model (CAPM). This paper considers the testability of the APT and points out the irrelevance for testing of the approximation error. We refute Shanken's objections, including his assertion that Roll's critique of the CAPM is applicable to the APT. We also explain the testability of the APT on subsets, and we explore the relationship between the APT and the CAPM. [ABSTRACT FROM AUTHOR]

Previous work by the authors has described how optimal portfolios can be assembled given various assumptions about the variance covariance arrangement of stock returns, and stipulating the existence of a risk-free asset. The current paper offers additional simplification by relaxing the requirement for a risk-free asset. The authors show how to construct a complete frontier of efficient portfolios for the single-index model, and for when identical correlation coefficients prevail among all stocks.

The continuing keynesian-monetarist debate has resulted in increasing attention being focused on the channels of monetary policy. The issue is important for its policy implications and because it divides Keynesians and monetarists; and also because of its implications with respect to the appropriate degree of aggregation in macro econometric models. Support for the single equation approach derives largely from the complexity and uncertainty about the transmission mechanism of monetary policy. The purpose of this paper is to examine commercial bank portfolio changes as one possible link in the money-spending nexus and more specifically to test the hypothesis that changes in commercial bank portfolio composition affect the income velocity of money. Theoretical rationalizations for such a causal relationship have been provided by Warren Smith, William Silber, and Paul Anderson, and Silber and Anderson have since provided impressive empirical evidence in support of such a relationship. With the exception of a brief discussion by Leonall Andersen, criticism of this hypothesis has been negligible. Silber's empirical study is, in terms of policy implication, the most important work in this area and consequently will be the focal point of this paper. The bank portfolio-velocity hypothesis will be briefly discussed, then empirical results will be presented using multiple regression analysis of a distributed lag model. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to investigate the opposite case: What is the impact of ever lengthening revision horizon on the optimal portfolio of a mean-variance investor? We do not intend to examine in this paper what will be the overall division of the investors' wealth between the riskless asset and the risky portfolio but rather we will determine how in the framework of the mean-variance analysis the long-run investor will construct his risky portfolio. Neither do we intend to examine the adequacy of the mean-variance criterion for this investment in light of the considerable skewness of multiperiod multiplicative returns. The purpose of this paper is to investigate the opposite case: What is the impact of ever lengthening revision horizon on the optimal portfolio of a mean-variance investor? We do not intend to examine in this paper what will be the overall division of the investors' wealth between the riskless asset and the risky portfolio but rather we will determine how in the framework of the mean-variance analysis the long-run investor will construct his risky portfolio. Neither do we intend to examine the adequacy of the mean-variance criterion for this investment in light of the considerable skewness of multiperiod multiplicative returns. [ABSTRACT FROM AUTHOR]

Background: Caries-affected dentine is the common bonding substrate when treating a patient. At present, there are many methods used for caries removal. The aim of this study was to evaluate the microtensile bond strength of two adhesives (Clearfil Protect Bond and OptiBond Solo Plus Total-Etch) to caries-affected dentine after three different caries removal methods.Methods: Extracted carious human third molars were used and caries-affected dentine surfaces were obtained from one of the three removal methods: (i) round steel bur in a slow-speed handpiece; (ii) Er:YAG laser; or (iii) 600-grit silicon carbide abrasive paper. Each of the adhesives was used to bond resin composite to the caries-affected dentine according to the manufacturers' instructions. Hourglass-shaped specimens were prepared and stressed in tension at 1mm/min. Data were analysed using two-way analysis of variance and least significant difference test.Results: Clearfil Protect Bond showed significantly lower bond strength than OptiBond Solo Plus Total-Etch after caries removal with round steel bur, but the opposite was found for specimens treated with silicon carbide abrasive paper. For laser-treated dentine, no significant differences between the adhesives were revealed.Conclusions: Besides the differences in adhesives, different caries removal methods seem to influence resin adhesion to caries-affected dentine. [ABSTRACT FROM AUTHOR]

This paper analyzes the effect of error correlation on the SISRE bounding for GPS and Galileo satellites. For a given period of data collection, it computes the effective number of independent samples contained in a dataset applying an estimation variance analyses. Results show that the time between effective independent samples is highly dependent on the constellation and onboard clock type. On one hand, GPS satellites equipped with Rubidium clocks exhibit significantly longer error correlation than those with onboard Cesium clocks. On the other hand, Galileo satellites show substantially shorter correlation time among samples with less variability on a monthly basis. This paper also introduces a methodology to compute SISRE bounding accounting for the limited number of independent samples. Using a Bayesian approach, it computes the so‐called uncertainty factor by which the Gaussian distribution needs to be inflated in order to account for the observation data independence. [ABSTRACT FROM AUTHOR]

Background: This paper is a follow‐up study continuing the COVISTRESS network previous research regarding health‐related determinants. Objective: The aim was to identify the main consequences of COVID‐19 lockdown on Body MassIndex and Perceived Fragility, related to Physical Activity (PA), for different categories of populations, worldwide. Design: The study design included an online survey, during the first wave of COVID‐19 lockdown, across different world regions. Setting and participants: The research was carried out on 10 121 participants from 67 countries. The recruitment of participants was achieved using snowball sampling techniques via social networks, with no exclusion criteria other than social media access. Main outcome measures: Body MassIndex, Physical Activity, Perceived Fragility and risk of getting infected items were analysed. SPSS software, v20, was used. Significance was set at P <.05. Results: Body MassIndex significantly increased during lockdown. For youth and young adults (18‐35 years), PA decreased by 31.25%, for adults (36‐65 years) by 26.05% and for the elderly (over 65 years) by 30.27%. There was a high level of Perceived Fragility and risk of getting infected for female participants and the elderly. Correlations between BMI, Perceived Fragility and PA were identified. Discussion and Conclusions: The research results extend and confirm evidence that the elderly are more likely to be at risk, by experiencing weight gain, physical inactivity and enhanced Perceived Fragility. As a consequence, populations need to counteract the constraints imposed by the lockdown by being physically active. [ABSTRACT FROM AUTHOR]

The article presents a commentary on the paper "Mean-Variance Versus Direct Utility Maximization," by Y. Kroll, H. Levy, and H. G. Markowitz. The author acknowledges that the analysis satisfactorily resolved both the multiplicative and additive scaling difficulties. He notes however that the paper introduced a new set of problems because of the arbitrary nature of the expected utility ratio. The author says an appropriate approach would map expected utility values for all utility functions having the same rankings into the same values, for purposes of comparison.

Pseudofactorialism is defined as 'the invalid statistical analysis that results from the misidentification of two or more response variables as representing different levels of an experimental variable or treatment factor. Most often the invalid analysis consists of use of an (n + 1)-way anova in a situation where two or more n-way anovas would be the appropriate approach'. I and my students examined a total of 1362 papers published from the 1960s to 2009 reporting manipulative experiments, primarily in the field of ecology. The error was present in 7% of these, including 9% of 80 experimental papers examined in 2009 issues of Ecology and the Journal of Animal Ecology. Key features of 60 cases of pseudofactorialism are tabulated as a basis for discussion of the varied ways and circumstances in which the error can occur. As co-authors, colleagues, editors and anonymous referees and editors who approved them for publication, a total of 459 persons other than the senior authors shared responsibility for these 60 papers. Pseudofactorialism may sometimes be motivated by a desire to test whether different response variables respond in the same way to treatment factors. Proper procedures for doing that are briefly reviewed. A major cause of pseudofactorialism is the widespread failure in statistics texts, primary literature and documentation for statistics software packages to distinguish the three major components of experimental design - treatment structure, design structure, response structure - and clearly define key terms such as experimental unit, evaluation unit, split unit, factorial and repeated measures. A quick way to check for the possible presence of the pseudofactorialism is to determine whether the number of valid experimental units in a study is smaller than (i) the error degrees of freedom in a multi-way anova; or (ii) the total number of tallies ( N) in a multi-way contingency table. Such situations also can indicate the commission of pseudoreplication, however. [ABSTRACT FROM AUTHOR]

Open systems theory offers a conceptual platform to understand how systems can be effective in adapting to their environments through purposeful action. It is relevant to the performance of national systems of innovation: open‐oriented countries are more likely to be successful in innovation because of the knowledge exchange between international organizations and organizations within the same country. In this paper, the open systems concept is defined and measured by a number of factors including extent of open trade, information and communication technology development, and online government service measures. In this study, the relationship between the measures of openness and the level of innovation of each country (measured using the Global Innovation Index) is analysed using analysis of variance, with results indicating a positive relationship. The theoretical contribution resides in the argument that a nation's openness relates to innovation capability and that this can be assessed by the factors in the model used in the paper. We argue that rather than focusing on innovation, countries should consider developing an open systems platform for innovation by maximizing their interactions with the international environment and developing mechanisms to circulate knowledge internally within the country. This should result in a supportive context where innovations can emerge. © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper studies the interrelationships in the strategic profile of a sample of small firms, and, by using cross-sectional analysis, attempts to identify any evidence to support the 'stages of growth' theories. Three surrogates for comparative growth were used in the analysis: number of employees, sales turnover, and profitability. A cluster analysis identified eight different 'types of small firms characterized by 'internal variables of ownership, management, and product structure; and the 'external' variables of product/market positioning. Analysis of variance tests found no significant differences between the clusters with regard to size. The results suggest that firms do change. but not necessarily in any prescribed sequence. Indeed, the evidence presented in the paper suggests that future research should be focused on developing theories which better describe the heterogeneity of the sector by analyzing the development within clusters of firms rather than seeking generalized over-arching theories. [ABSTRACT FROM AUTHOR]

This paper provides empirical support for the notion that Autoregressive Conditional Heteroskedasticity (ARCH) in daily stock return data reflects time dependence in the process generating information flow to the market. Daily trading volume, used as a proxy for information arrival time, is shown to have significant explanatory power regarding the variance of daily returns, which is an implication of the assumption that daily returns are subordinated to intraday equilibrium returns. Furthermore, ARCH effects tend to disappear when volume is included in the variance equation. [ABSTRACT FROM AUTHOR]

This paper provides new tests of the arbitrage pricing theory (APT). Test results appear to be extremely sensitive to the number of securities used in the two stages of the tests of the APT model. New tests also indicate that unique risk is fully as important as common risk. While these tests have serious limitations, they are inconsistent with the APT. [ABSTRACT FROM AUTHOR]

This paper presents a method for solving the mean-variance portfolio selection problem that is applicable to the case where the number of securities is nondenumerably infinite. Necessary conditions for the existence of an optimal portfolio density are obtained and an expression for the efficient frontier is derived. The conditions for the existence of an optimal portfolio of continuously maturing bonds when their covariance matrix is singular are used to derive an arbitrage-free bond pricing equation. A method for estimating the covariance matrix and the associated efficient frontier is presented. [ABSTRACT FROM AUTHOR]

With a short sales restriction, there may be switching points along the mean variance frontier corresponding to changes in the set of assets held. Traditional wisdom holds that each switching point corresponds to a kink, while Ross has claimed that kinks never occur. This paper shows that the truth lies between the two views, since the efficient frontier may or may not be kinked at a switching point. There is some indication that kinks are rare, since a kink corresponds to a portfolio in which all assets have the same expected return. [ABSTRACT FROM AUTHOR]

In this paper a discrete mixture of normal distributions is proposed to explain the observed significant kurtosis (fat tails) and significant positive skewness in the distribution of daily rates of returns for a sample of common stocks and indexes. Stationarity tests on the parameter estimates of this discrete mixture of normal distributions model revealed significant differences in the mean estimates that can explain the observed skewness and significant differences in the variance estimates that can explain the observed kurtosis. An alternative explanation for the observed fat tails is the symmetric student model. The result of a comparison between the models is that the discrete mixture of normal distributions model has substantially more descriptive validity than the student model. [ABSTRACT FROM AUTHOR]

This paper presents an analysis of the testability of the mean variance efficiency of a market index when the returns on some components of the index itself are not perfectly observable. The results are basically not supportive of the notion that mean variance efficiency is testable on a subset of the assets. Bounding the market share of the missing asset and its expected return is not sufficient to produce a valid test. When the variance of the missing asset is bounded, and the amount of wealth that might be missing is small, it is possible, in principle, to reject correctly the mean variance efficiency of a market index. [ABSTRACT FROM AUTHOR]

Levy and Markowitz showed, for various utility functions and empirical returns distributions, that the expected utility maximizer could typically do very well if he acted knowing only the mean and variance of each distribution. Levy and Markowitz considered only situations in which the expected utility maximizer chose among a finite number of alternate probability distributions. The present paper examines the same questions for a case with an infinite number of alternate distributions, namely those available from the standard portfolio constraint set. [ABSTRACT FROM AUTHOR]

The paper relates two phenomena in the stock market: the high return during the month of January and the apparent existence of widespread sales of stocks for tax purposes towards the end of the fiscal year. The findings suggest that, due to the tax-induced sales, the price of many stocks over the last 35 years was temporarily depressed in December but recovered in the following January. This price recovery is a major contributor to the high returns observed in January. The tax effect is present in firms of all sizes but much more pronounced for small firms. The analysis also indicates that a more precise identification of the tax-switch candidates may prove that the tax-induced sales are, in fact, the sole contributor to the high January's returns. [ABSTRACT FROM AUTHOR]

This paper examines the informativeness of embedded value reporting to stock price by investigating the cross‐sectional variations in life insurers' price to embedded value ratios. By conducting variance decomposition analysis on a dataset provided by Morgan Stanley, we find that 15 percent (40 percent) of the difference between embedded value and stock price can be explained by growth opportunities and future stock returns in the short (long) run. One‐third and two‐thirds of the unexplained variation are attributed to firm‐ and country‐specific factors, respectively. The above findings provide investors with a better understanding of the value relevance of embedded value reporting. [ABSTRACT FROM AUTHOR]

The article discusses the effects of accounting variations on decision making and the paper "An Experimental Design for Study of Effects of Accounting Variations in Decision Making" by R.E. Jensen. The statistical methodology and design used by Jensen in his research of the effects of alternative accounting reporting techniques in the selection of portfolios and their security evaluation is examined as is the data collection. The limitation of whether or not there was adequate control over the research environment and the probability level of the statistical tests is not known in Jensen's paper because he does not mention these issues.

The purpose of the present paper is to examine the adequacy of variance as a measure of risk. Despite the abundance of literature on risk and portfolio diversification, virtually all of which uses variance as the measure of risk, there has been little progress on this problem beyond the original contributions. Tobin has pointed out that variance is the appropriate measure of risk if either the probability distribution of returns can be fully described by two parameters (e.g., normal) or the investor utility functions can be approximated by quadratics. Markowitz has suggested the possibility of using the semi-variance as a measure of risk, but for the most part his analysis of risk and portfolio diversification closely parallels that of Tobin. The subsequent literature has in general used variance as a measure of risk without further consideration. Moreover, those studies which have examined the measurement of risk explicitly either have provided only minor modifications to the Tobin-Markowitz analysis or have proposed alternative measures of risk which have been generally ignored. Thus, whether for reasons of convenience, theory or tradition, variance continues to be almost universally used as the measure of risk in portfolio models. The present paper takes a different approach to the problem of using variance as a measure of risk and reaches the conclusion that variance is ambiguous and yields conflicting results when calculated from information generally available to decision makers. If variance is in fact the best measure of risk (and thus appropriate for computing the locus of efficient portfolios and calculating the discount for uncertainty in capital asset prices) the question remains: which variance? In the case of a stock portfolio, the variance in the rate of return for an individual stock may be calculated from price information recorded over a shorter or longer period of time; moreover, observations from the same period of time when aggregated u... [ABSTRACT FROM AUTHOR]

Summary 1.An analysis of variance (anova) or other linear models of the residuals of a simple linear regression is being increasingly used in ecology to compare two or more groups. Such a procedure (hereafter, ‘residual index’) was used in 8% and 2% of the papers published during 1999 in the Journal of Animal Ecology and in Ecology, respectively, and has been recently recommended for studying condition. 2.Although the residual index is similar to an analysis of covariance (ancova), it is not identical and is incorrect for at least four reasons: (i) the regression coefficient used by the residual index differs from the one used in ancova and is not the least-squares estimator of the model. (ii)in contrast to the ancova, the error d.f. in the residual index are overestimated because of the estimation of the regression coefficient. (iii)the residual index also assumes the homogeneity of regression coefficients (parallelism assumption), which should be tested with a special ancova design. (iv)even if the assumptions of the linear model hold for the original variables, they will not hold for the residuals. 3.More importantly, the residual index is an ad hoc sequential procedure with no statistical justification, unlike the well-known ancova. For these reasons, I suggest that a t-test or an anova of the residuals should never be used in place of an ancova to study condition or any other variable. [ABSTRACT FROM AUTHOR]

In the previous paper, Cooley and Houck examined the simultaneous use of common and antithetic random number streams as a variance-reduction strategy for simulation studies employing response surface methodology (RSM). Our paper supplements their work and further explores pseudorandom number assignments in response surface designs. Specifically, an alternative strategy for assigning pseudorandom numbers is proposed; this strategy is more efficient than that given by Cooley and Houck, especially when more than two factors are involved. [ABSTRACT FROM AUTHOR]

This paper documents the statistical properties of contemporary business fluctuations in the United Kingdom. We study the period 1956-90 using quarterly, detrended data on key aggregate variables. We compute selected moments of the data, compare our results with those for the United States, and rigorously test for dynamic instabilities. Our findings confirm the existence of substantive cyclical regularities, both across countries and across time. Some notable cross-country differences are also identified. Conclusions about stability are shown to be potentially sensitive to the method of testing. In general, cross-correlations are appreciably more stable than standard deviations. [ABSTRACT FROM AUTHOR]

Background: Comparative optimism, the belief that negative events are more likely to happen to others rather than to oneself, is well established in health risk research. It is unknown, however, whether comparative optimism also permeates people's health expectations and potentially behaviour during the COVID‐19 pandemic. Objectives: Data were collected through an international survey (N = 6485) exploring people's thoughts and psychosocial behaviours relating to COVID‐19. This paper reports UK data on comparative optimism. In particular, we examine the belief that negative events surrounding risk and recovery from COVID‐19 are perceived as more likely to happen to others rather than to oneself. Methods: Using online snowball sampling through social media, anonymous UK survey data were collected from N = 645 adults during weeks 5‐8 of the UK COVID‐19 lockdown. The sample was normally distributed in terms of age and reflected the UK ethnic and disability profile. Findings: Respondents demonstrated comparative optimism where they believed that as compared to others of the same age and gender, they were unlikely to experience a range of controllable (eg accidentally infect/ be infected) and uncontrollable (eg need hospitalization/ intensive care treatment if infected) COVID‐19‐related risks in the short term (P <.001). They were comparatively pessimistic (ie thinking they were more at risk than others for developing COVID‐19‐related infection or symptoms) when thinking about the next year. Discussion: This is one of the first ever studies to report compelling comparative biases in UK adults' thinking about COVID‐19. [ABSTRACT FROM AUTHOR]

In a recent paper we extended and refined some tools introduced by O'Hagan for criticism of Bayesian hierarchical models. Especially, avoiding double use of data by a data-splitting approach was a main concern. Such tools can be applied at each node of the model, with a view to diagnosing problems of model fit at any point in the model structure. As O'Hagan, we investigated a Gaussian model of one-way analysis of variance. Through extensive Markov chain Monte Carlo simulations it was shown that our method detects model misspecification about as well as the one of O'Hagan, when this is properly calibrated, while retaining the desired false warning probability for data generated from the assumed model. In the present paper, we suggest some new measures of conflict based on tail probabilities of the so-called integrated posterior distributions introduced in our recent paper. These new measures are equivalent to the measure applied in the latter paper in simple Gaussian models, but seem more appropriately adjusted to deviations from normality and to conflicts not concerning location parameters. A general linear normal model with known covariance matrices is considered in detail. [ABSTRACT FROM AUTHOR]

This paper examines the dynamic relationship between interest rates, inflation and economic growth using a long dataset for the UK. The approach adopted enables us to identify structural breaks in the dynamic system (vector autoregression (VAR)). We find interest rates respond much more strongly to growth and inflation over recent decades, and forecast error variance decomposition analysis indicates there is increasing interconnectedness between the variables in recent years. Economic policymakers need to carefully monitor the linkages between these variables and be prepared to adjust their monetary policy tools when faced with structural changes. [ABSTRACT FROM AUTHOR]

This paper explores the implications that spatial effects can hold for the application of measures of σ-convergence. The bias of a common indicator of σ-convergence is examined for a family of spatial process models including: [a] spatial lag, [b] spatial error, and [c] spatial moving average. We show that the measure of σ-convergence is sensitive to a number of distinct influences including global dispersion, spatial dependence, and a variety of forms of spatial heterogeneity. We suggest a decomposition of the convergence indicator into two components: one reflecting global dispersion, and one reflecting the influence of spatial effects. We then illustrate this approach with a case study of the U.S. states over the 1929–2000 period. [ABSTRACT FROM AUTHOR]

Background: Double‐eyelid blepharoplasty is a popular cosmetic procedure in Asia; however, there are some drawbacks to this procedure for mild blepharoptosis. Enhancing movement of the levator aponeurosis can correct blepharoptosis through the release of fibrous web bands present between the preaponeurotic fat pad and levator aponeurosis. Aim: To improve our understanding of the anatomical link between the levator aponeurosis and orbital septum fat and to introduce that the release of the link can provide favorable results in double‐eyelid blepharoplasty. Patients/Methods: We included patients with latent ptosis or subclinical blepharoptosis who underwent double‐eyelid blepharoplasty with the release of fibrous web bands between June 2021 and March 2023. Mild ptosis was corrected following complete release of the fibrous bands beneath the preaponeurotic fat pad. Patients were followed up for 4–12 months postoperatively, and surgical outcomes were evaluated. Patient demographic variables and photographs were collected pre‐ and postoperatively. Patients, surgeons, and laypersons were asked to evaluate the outcomes postoperatively. The Friedman's nonparametric (for repeated measures) two‐way analysis of variance was used for statistical analyses. Results: Outcomes were assessed in 45 individuals with an average monitoring period of 6.9 months. There were no cases of incomplete eyelid closure or upper eyelid ectropion. Over 50% of the surgical outcomes were deemed "satisfactory" by each of the three groups in relation to the widening of the eyelid fissure. Most of the examined patients demonstrated favorable long‐term results. Conclusions: Fibrous web bands are implicated in subclinical or mild blepharoptosis. The release of fibrous web bands between the preaponeurotic fat pad and levator aponeurosis can provide favorable results in double‐eyelid blepharoplasty. [ABSTRACT FROM AUTHOR]

Aim: To investigate whether resilience mediates the connection between caregiver burden and hope among caregivers of patients with inflammatory bowel disease (IBD). Design: A cross‐sectional study. Methods: Two hundred patients with IBD were conveniently sampled from two tertiary hospitals in Jiangsu Province, China. The main instruments involved the Zarit Burden Interview, the 10‐item Connor‐Davidson resilience scale, and the Herth Hope Index. We conducted descriptive analysis and Pearson correlations using SPSS 25.0. The PROCESS v3.3 macro analysed the mediating effect. We report the results in line with the STROBE checklist. Results: Caregiver burden was significantly negatively connected with hope and resilience, whereas resilience positively correlated with hope. The mediation role of resilience was significant in the relationship between caregiver burden and hope, with mediating effects accounting for 47.86% of the overall effect. Conclusions: Resilience partially mediates the association between caregiver burden and hope among patients with IBD. This finding highlights the protective role of resilience in undermining caregiver burden and strengthening hope. Implications for Practice: In clinical practice, healthcare providers should perform routine psychological assessments for caregivers of patients with IBD. Furthermore, resilience training should be incorporated into interventions to alleviate caregiver burden and enhance hope. Patient or Public Contribution: None. [ABSTRACT FROM AUTHOR]

Requiring no fuel for generation and negligible material/energy for operation and maintenance, photovoltaic (PV) systems have environmental impacts mostly due to the production of modules and the commissioning of power plants. Thus, extending the service lifetime of these systems from 30 to 40 years through an enhanced lamination process for module production potentially reduces environmental impacts per unit energy generated. Life cycle assessment is employed to evaluate the environmental impacts under scenarios for resource utilizations for the new lamination process, operation and maintenance requirements in the extended service lifetime, and degradation rates of the devised modules. Extending the service lifetime significantly reduces environmental impacts across categories, with a 21–27% reduction in global warming potential on the pessimistic and optimistic ends. At least 20% impact reduction is achieved in most impact categories, even under a pessimistic scenario. Considering uncertainty models in the life cycle inventories, samples are generated for scenarios via Monte Carlo simulation, and with significant improvements with large effects in most environmental impact categories, deterministic impact comparisons are supported by ANOVA and Tukey tests. Production strategies for more durable and reliable PV modules have a significant potential in contributing to global sustainability efforts. [ABSTRACT FROM AUTHOR]

Poor diet quality (diet diversity and animal‐source food [ASF] consumption) during childhood negatively affects growth, development, behaviour and physiologic function in later life. Relatively less is known about the impact of poor diet on the growth of school‐age children compared to children <5 years of age, especially in low/middle‐income countries. A better understanding of delivery strategies for effective interventions to improve diet and hence growth in school‐age children is needed. A 36‐month longitudinal controlled impact evaluation in rural Nepal assessed the nutrition and growth of children <5 years of age in families assigned via community clusters to full package intervention (community development, training in nutrition [during pregnancy and for children <5 years] and livestock husbandry), partial package (training only) or control (no inputs). Concurrent data were collected prospectively (baseline plus additional four rounds) on school‐age children (5–8 years at baseline) in these households; the present study analysed findings in the cohort of school‐age children seen at all five study visits (n = 341). Diet quality improved more in the full package school‐age children compared to those in partial package or control households. full package children consumed more ASF (β +0.40 [CI 0.07,0.73], p < 0.05), more diverse diets (β +0.93 [CI 0.55,1.31], p < 0.001) and had better head circumference z‐scores (β +0.21 [CI 0.07,0.35], p < 0.01) than control children. In conclusion, a multi‐sectoral community development intervention was associated with improvements in diet and growth of school‐age children in rural Nepal even though the intervention focused on the diet of children <5 years of age. The diet and growth of school‐age children can be favourably influenced by community‐level interventions, even indirectly. Key messages: Relatively less is known about the factors that influence diet quality and growth in school‐age children compared to younger children, especially in low‐ and middle‐income countries.Better diet quality and growth were found among school‐age children whose families participated in an impact study multi‐sectoral intervention compared to children in control families or those whose families only received nutrition training.Diet and growth of school‐age children can be favourably influenced by community‐level interventions. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate household food security (access) level and the dietary diversity of households in the Nsukka Local Government Area in South‐eastern Nigeria. From 20 local communities of Nsukka, 390 women were randomly sampled from the women's group and asked to complete a survey that determined the Household Food Insecurity Access Scale scores and the Household Dietary Diversity Scores (HDDS). The descriptive results indicated a high level of food insecurity with 82.6% households reporting various degrees of food insecurity. Over half of the sampled population experienced insufficient food quality. They either ate unwanted food (65.9%), limited variety (63.1%), or unpreferred food (64.6%). Some households experienced insufficient food intake by going a whole day without food (38.2%), go to sleep hungry (45.1%), or have no food of any kind (49%). The analysis of variance showed no significant difference (p = 0.428) in the food security level of households headed by males as compared with those headed by females. Approximately 53.6% of households fell at or below the average HDDS; males headed 48% of these households, while females headed 64%. The chi‐square test indicated factors associated with household food security including age, education, work status and income, whereas the gender of the household head, household size and marital status were not significantly associated. Public–private partnerships, nutrition orientation and food intervention programs could improve food security in this area. Key messages: This study found a high level of household food insecurity in Nsukka Local Government Area (NLGA) at 82.6%, with 60.3% of households being severely food insecure and 13.3% and 9% mildly and moderately food insecure, respectively, resulting in anxiety for most households.The majority ate limited variety, unwanted and unpreferred food, with more households consuming starchy foods than protein‐rich foods. About 53.6% households fell at or below average dietary diversity.There was no difference in household food security based on the gender of the household head.Food security was associated with education, age, income and work status.Rural households within NLGA require food intervention programs to alleviate food insecurity. [ABSTRACT FROM AUTHOR]

The note comments on the article by T. Kloek from the 1972 issue of "Econometrica" about the consistency of variance estimation in the linear model. It considers the usual linear model with n observations and k explanatory variables which is formally described by yn = Xnβ + εn. The note shows that T. Kloek's assumption that rank (Xn) = k (at least for some n ≥ n0) is not necessary either to establish consistency.

Scientific techniques for inventory management typically are applied to systems containing many items. Such techniques require an estimation of the demand variance (and mean) of each item from historical data. This research demonstrates a significant potential for improvement in system cost performance from using least-squares regression fits of a variance-to-mean functional relation instead of the standard statistical variance estimate. Even when there is a moderate degree of heterogeneity among items and when the form of the variance-to-mean relation is misspecified, substantial cost savings may be realized. The cost of statistical uncertainty may be reduced by half. The research also provides evidence that system cost is fairly insensitive to the number of items used to fit the regression. This paper provides the underlying reason why a regression-derived variance estimator yields lower cost: it is less variable than the usual individual item variance estimator. [ABSTRACT FROM AUTHOR]

The objective of this paper is to introduce the Wiener-Kolmogorov (WK) method to business researchers and to applied workers who have an interest in spectral techniques. It is seen that the advantage of the WK method is that it provides better forecasts than autoregressive regression analysis when the order of the true autoregressive process is large. The paper outlines the steps involved in the WK method. Also discussed is a laborsaving feature to guide one at the outset as to whether the WK algorithm should be used. A numerical example is given to illustrate the application of the method in time-series forecasting. [ABSTRACT FROM AUTHOR]

This paper proposes a method, canonical rotation analysis, which facilitates the substantive interpretation of results in multivariate analysis. Canonical rotation analysis is developed as a model which integrates multivariate least squares approaches and the varimax rotation criterion. The generalized applicability of the model to canonical correlation, multiple discriminant analysis, and multivariate analysis of variance is developed. The advantages and limitations of canonical rotation analysis are discussed and illustrated in the context of an industrial marketing research problem. [ABSTRACT FROM AUTHOR]