Estimation Of Random Effects Research Articles

A systematic review and meta-analysis of the prognostic value of radiomics based models in non-small cell lung cancer treated with curative radiotherapy

Background and purposeRadiomics allows extraction of quantifiable features from imaging. This study performs a systematic review and meta-analysis of the performance of radiomics based prognostic models in non-small cell lung cancer (NSCLC). Materials and methodsA literature review was performed following PRISMA guidelines. Medline, EMBASE and Cochrane databases were searched for articles investigating radiomics features predictive of overall survival (OS) in NSCLC treated with curative intent radiotherapy. A random-effects meta-analysis of Harrell’s Concordance Index (C-index) was performed on the performance of radiomics models. ResultsOf the 2746 articles retrieved, 40 studies of 55 datasets and 6223 patients were eligible for inclusion in the systematic review. There was significant heterogeneity in the methodology for feature selection and model development. Twelve datasets reported the C-index of radiomics based models in predicting OS and were included in the meta-analysis. The C-index random effects estimate was 0.57 (95% CI 0.53–0.62). There was significant heterogeneity (I2 = 70.3%). ConclusionsBased on this review, radiomics based models for lung cancer have to date demonstrated modest prognostic capabilities. Future research should consider using standardised radiomics features, robust feature selection and model development, and deep learning techniques, absolving the need for pre-defined features, to improve imaging-based models.

Fiscal decentralization and convergence in government spending in Malaysia

ABSTRACTIn this study, we highlight the influence of the federal system on the development expenditure of the states, which is crucial for socio‐economic development. First, we examine whether there is a convergence in development expenditure across Malaysian states. Second, we investigate the importance of decentralization in affecting the pattern of development expenditure in the short‐term and in the long‐term. The convergence analysis utilizes annual growth data from 2000 through 2015 for the short‐term and the averages of 3‐ and 5‐year growth for the long‐term. In this study, we employ the panel data approaches of pooled OLS, fixed effects and random effects estimation procedures. The findings provide empirical evidence of the convergence of development expenditure across the states in Malaysia in both the short‐term and the long‐term. Generally, all fiscal decentralization indicators (state per capita revenue, state own‐source per capita revenue, state own‐source revenue as a share of total revenue and inter‐state fiscal capacity) are imperative in influencing the fiscal behaviour of state governments in Malaysia. These indicators, as well as assistance from the federal government in the form of transfer payment, are very much needed to strengthen the expenditure capacity of the Malaysian states.

Air pollution and income distribution: evidence from Chinese provincial panel data.

In recent years, air pollution has caused an increasing number of problems in China. Individual health and labour productivity, which are affected by air pollution may affect income distribution. Therefore, this article will analyse the effect of air pollution on income distribution. We investigated the evolution of air pollution in China over the past two decades. Fixed-effects and random-effects estimation approaches were used with data from 30 provinces in China from 1998 to 2017 to analyse the effect of air pollution on income distribution. Empirical results reveal that air pollution significantly worsens income distribution in China. Then we explored the mechanism by which air pollution affects income distribution, and found that increasing health expenditures and declining labour productivity mediate the effect of air pollution on income distribution. Considering the potential endogenous problems of air pollution affecting income distribution, the simultaneous equation model and the instrumental variable approach are employed to overcome endogenous bias. Traditional mean regression was empirically found to overestimate the impact of air pollution on income distribution. Finally, some policy implications are proposed to improve air quality and income distribution.

The Household Secondary Attack Rate of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2): A Rapid Review.

BackgroundAlthough much of the public health effort to combat coronavirus disease 2019 (COVID-19) has focused on disease control strategies in public settings, transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) within households remains an important problem. The nature and determinants of household transmission are poorly understood. MethodsTo address this gap, we gathered and analyzed data from 22 published and prepublished studies from 10 countries (20 291 household contacts) that were available through 2 September 2020. Our goal was to combine estimates of the SARS-CoV-2 household secondary attack rate (SAR) and to explore variation in estimates of the household SAR. ResultsThe overall pooled random-effects estimate of the household SAR was 17.1% (95% confidence interval [CI], 13.7–21.2%). In study-level, random-effects meta-regressions stratified by testing frequency (1 test, 2 tests, >2 tests), SAR estimates were 9.2% (95% CI, 6.7–12.3%), 17.5% (95% CI, 13.9–21.8%), and 21.3% (95% CI, 13.8–31.3%), respectively. Household SARs tended to be higher among older adult contacts and among contacts of symptomatic cases. ConclusionsThese findings suggest that SARs reported using a single follow-up test may be underestimated, and that testing household contacts of COVID-19 cases on multiple occasions may increase the yield for identifying secondary cases.

COVID-19 and investor sentiment influence on the US and European countries sector returns

Although some studies recently address the association between COVID-19 sentiment and returns, volatility, or stock trading volume, no one conducts an analysis to measure the impact of investor rationality or irrationality on the influence on countries and sectors’ returns. This work creates a text media sentiment and combines its influence with the outbreak cases on the stock market sector returns of the US, Europe, and their main countries most affected by the pandemic. This allows us to perceive the ranking impact of rationality or irrationality on country and sector stock returns. This work applies a random-effects robust panel estimation, with an M-estimator. This paper concludes that US returns are more sensitive to sentiment, and thus more prone to irrational factors than confirmed cases compared to Europe and that country factors influence the returns differently. In Italy and Spain as the most punished countries in Europe apart from the UK, present sector indexes return more reactive to verified cases, or rationality, namely, tourism, real estate, and the automobile (this last one in Italy). The importance of this work resides in providing a new in-depth analysis of irrational behavioral metrics among countries, which allows for comparison. Moreover, it allows observing which sectors’ and which countries’ asset returns are most sensitive to rational or irrational expressions of events, allowing for arbitraging, financial planning for investors, decision-makers, and academia on an in and out of pandemic context. AcknowledgmentThis work is funded by National Funds through the FCT – Foundation for Science and Technology, I.P., within the scope of the project Refª UIDB/05583/2020. Furthermore, we would like to thank the Research Centre in Digital Services (CISeD) and the Polytechnic Institute of Viseu for their support.

The effectiveness of FX interventions: A meta-analysis

There is ample empirical literature centering on the effectiveness of foreign exchange intervention (FXI). Given the mix of objectives and country-heterogeneity, the general lack of consensus thus far is no surprise. We shed light on this debate by conducting the first comprehensive meta-analysis in the FXI literature, with 279 reported effects that stem from 74 distinct empirical studies. We cover estimations conducted in 19 countries across five decades. Overall, our meta-survey reports an average depreciation of domestic currency of 1% and a reduction of exchange rate volatility of 0.6%, in response to a $1 billion US dollar purchase. Results are qualitatively confirmed but smaller in size under fixed and random-effect estimations. When narrowing in on different economic factors, we find that effects are magnified for cases consistent with the monetary trilemma (greater if financial openness and monetary independence are low). Effects are also larger in emerging than advanced economies, when banking crises remain mild, and when interventions are large in size and are announced.

Is meconium exposure associated with autism spectrum disorders in children?

BackgroundThe results differ among published studies regarding exposure to meconium and the risk of developing autism spectrum disorders (ASDs).PurposeThe present study pooled all of the epidemiologic studies retrieved from broader databases on the association between meconium exposure and risk of developing ASD in children.MethodsThe Web of Science, PubMed, Scopus, and Google Scholar databases were searched without language restrictions for articles published between their inception to February 20, 2020, using relevant keywords. The pooled odds ratios (ORs) and their 95% confidence intervals (CIs) were calculated as random-effect estimates of the associations among studies. A subgroup analysis was conducted to explore any potential sources of heterogeneity among studies.ResultsThe pooled estimate of OR reported a weakly significant association between meconium exposure and ASD development in children (OR, 1.13; 95% CI, 1.03–1.24). There was low heterogeneity among the articles reporting risk for ASD among children (I2=19.3%; P=0.259). The results of subgroup analysis based on meconium exposure showed a significant association between a meconium-stained neonate and ASD development (OR, 1.18; 95% CI, 1.11–1.24).CouclusionMeconium exposure was weakly associated with an increased risk of ASD. However, more evidence based on large prospective cohort studies is required to provide conclusive evidence about whether meconium exposure is associated with an increased risk of ASD development.

The Effect of Problem-Based Learning (PBL) Model On Mathematical Communication Skills of Junior High School Students – A Meta-Analysis Study

This study aims to integrate research findings on the effect of the Problem-Based Learning (PBL) model on the mathematical communication skills of junior high school students in Indonesia since 2014. The research method used is a meta-analysis with many samples studied, namely 12 published articles. The sampling technique used was purposive sampling. The effect size transformation is based on the g hedge equation calculated using the Comprehensive Meta-Analysis (CMA) application. Based on the results of the analysis, the combined effect of PBL on mathematical communication skills is 0.791, with the high influence criteria according to the random-effect estimation model. There are four criteria considered, namely, sample size, year of study, source of journal publication, and grade level. The results of the heterogeneity test seen based on the variables studied showed that the effect of the PBL learning model was not significantly different from the three moderator variables in terms of sample size, year of study, and publication journals and very different in terms of grade level. This finding is surprising because the random-effects model, as determined by the heterogeneity test, showed variation between effect sizes. Only one of the four variables causes this variation. Therefore further research is needed, which includes more studies and the characteristics studied to describe it more accurately.

RURAL DEVELOPMENT POLICY AND POVERTY ALLEVIATION: THE CASE OF VILLAGE FUNDS IN ACEH PROVINCE, INDONESIA

Village funds is still a new fiscal policy that was initially launched in 2015 by the seventh president of Indonesia, “Joko Widodo”, as his pilot project. Some villages have significantly benefited from developments and improvements initiated by the policy. However, it also has been identified through various investigative analysis that not all village funds allocations transferred to local governments have been implemented effectively and efficiently. This research examines the relationship between the village funds allocations and poverty alleviation in Aceh province, Indonesia. Using a panel data model that provides random-effects estimations, it concludes the village funds allocations from the period of 2015 to 2018 cannot reduce the poverty rate in 23 regencies/municipalities in Aceh. Fiscal variables, government expenditure and government own revenue have also shown a positive relationship with the poverty rate. Furthermore, with fixed-effects estimation, village funds allocations also show the same result of its relationship with the number of people living in poverty. Meanwhile, one fiscal variable, GDRP has a negative and significant relationship with the number of people living in poverty. Some social variables, such as education and population have also had significant and negative effects on the poverty rate and the number of people living in poverty.

Banks’ Governance, Capital Structure and Performance in Ghana

The paper explores the mechanisms through which banks rely on good governance to attract more equity capital towards the improvement of their profitability. The study employed a panel data for twenty-nine commercial banks in Ghana between the years from 2003 to 2015, using the Generalized Method of Moments (GMM), Fixed Effects and Random Effects estimators. The results are robust notwithstanding the estimation method employed, that bank governance affects banks’ performance in Ghana. Larger board size improves return on the banks’ equity just as large proportion of directors with finance expertise induces bank performance. All estimates also show that equity funding has a negative and significant effect on bank performance. The paper also found evidence that good bank governance attracts equity capital which, in turn, induces greater profitability. The study recommends for managers and policymakers of banks to adopt policies that will position the banks to improve governance structure, to improve managerial expertise to drive bank performance. Admonitions to expand bank capitalisation should not be encouraged without recourse to the improvement in bank governance effectiveness.

Innovation and Human Development Perspectives in West Africa

Innovation during this era of globalization plays a crucial role in the growth and development of an economy. This study empirically investigates the role of research and development (innovation) on human development in West Africa (2004—2014). The estimation techniques utilized to carry out the objective are the standard variations of the Generalized least squares—Panel Fixed and Panel Random effects estimation techniques. The empirical results show that research and development in West Africa has a statistically significant positive impact on human development which emphasizes the potentials of human development to be harnessed by consistent research and development. The study recommends increased research and development (innovation) through adequate research and development funding and university-industry partnership for real human development problems to be solved.

Is the Balassa-Samuelson Hypothesis still relevant? Cross-country evidence from 1950 -2017

Abstract. We revisit the Balassa and Samuelson hypothesis based on the relationship between real exchange rate and total factor productivity relative to the United States and investigate with panel data set of 182 countries from 1950 to 2017. Results, suggest that there is an inverse relationship between the two, an increase in productivity results in an increase in real exchange rate and the findings supports the hypothesis. We use a range of tests including Arellano-Bond Dynamic Panel Data (both fixed and random effect) estimator and findings validates the hypothesis. All these additional tests confirm that the relationship between real exchange rate and relative factor producity are related in the long-run also. Keywords. Balassa–Samuelson effect; Exchange rate, Fixed effect model, Random effect model, Trade and globalization. JEL. C15, E31, F31, F41.

The Impact of Human Development on the Standard of Living in Alleviating Poverty: Evidence from Africa

The African Union 2030, 2063, and beyond strategic, focused on transformative economic growth and regional integration, empowering the populace and consolidating peace and society cannot be achieved without considering human development as synergies in elevating these policies. A large focus on empowering the populace through domestic credit can help this agenda be realized. For robustness sake, the researcher developed both subjective and objective measures to check the various relationships of the variable that helps to achieve the standard of living. Using data from the World Bank's development indicators and Human Development indicators from 1998 to 2017, the researcher examined human development reduces poverty. In this meta-analysis, the study empirically synthesizes a total of four African countries under study, fixed and random effects estimation, domestic credit and human development study find out these variables have a positive relationship of poverty which helps to improve the standard of living. The findings of this study have important implications for policy implementation and therefore, helps to improve the standard of living in the four countries under study.

The Effectiveness of FX Interventions: A Meta-Analysis

There is ample empirical literature centering on the effectiveness of foreign exchange intervention (FXI). Given the mix of objectives and country-heterogeneity, the general lack of consensus thus far is no surprise. We shed light on this debate by conducting the first comprehensive meta-analysis in the FXI literature, with 279 reported effects that stem from 74 distinct empirical studies. We cover estimations conducted in 19 countries across five decades. Overall, our meta-survey reports an average depreciation of domestic currency of 1% and a reduction of exchange rate volatility of 0.6%, in response to a $1 billion US dollar purchase. Results are qualitatively confirmed but smaller in size under fixed and random-effect estimations. When narrowing in on different economic factors, we find that effects are magnified for cases consistent with the monetary trilemma (greater if financial openness and monetary independence are low). Effects are also larger in emerging than advanced economies, when banking crises remain mild, and when interventions are large in size and are announced.

Urban-rural divide in foodborne illness in China: what can we learn from the socioeconomic factors?

Background China’s urban-rural divide, though still improving, can be seen from various sectors of the economy. The objective of this study is to explore how socioeconomic factors in and across both urban and rural areas explain the occurrence of foodborne illness in China. Over the last decades, food safety laws and regulations have been established in China, but more understanding about the food safety issues are needed in order to eliminate food safety hazards. Methods This study intends to estimate several panel data models in econometrics to obtain the average partial effects of many socioeconomic factors in and across urban and rural areas on per capita foodborne incidents and patients, respectively. Given the fractional nature of the two dependent variables, fractional probit models are estimated using both the Quasi Maximum Likelihood Estimation (QMLE) and the bootstrap Generalized Estimating Equations (GEE) approaches in addition to the standard estimation of panel data random effects, fixed effects, and Tobit models. China official data on foodborne incident and patient cases in each province and in each year from 2011 to 2018 are obtained from various issues of the China Health Statistical Yearbook. Additional data on 19 socioeconomic variables are obtained from various issues of the China Statistical Yearbook. Results The main results show that socioeconomic factors such as owning TVs, owning refrigerators, consumption expenditures and household income in urban or rural areas explain the per capita foodborne incidents or per capita foodborne patients differently, reflecting differences in people’s food safety awareness, food storage patterns, food markets, and income effects in the urban and rural areas. Socioeconomic factors such as urbanization and primary industry’s share of the gross regional product across areas tend to worsen the food safety problem. Improving regional economies and increasing government spending on public health could reduce the occurrence of foodborne illness. Conclusions It is suggested that governments take into account the social disparities of urban and rural areas when designing and implementing food safety policies. It is also suggested that a holistic approach is needed to resolve food safety issues by combining food safety control and management policies with soil and water management policies.

Transformed-likelihood estimators for dynamic panel models with a very small T

Conventional OLS fixed-effects and GLS random-effects estimators of dynamic models that control for individual-effects are known to be biased when applied to short panel data (T ≤ 10). GMM estimators are the most used alternative but are known to have drawbacks. Transformed-likelihood estimators are unused in political science. Of these, orthogonal reparameterization estimators are only tangentially referred to in any discipline. We introduce these estimators and test their performance, demonstrating that the unused orthogonal reparameterization estimator in particular performs very well and is an improvement on the commonly used GMM estimators. When T and/or N are small, it provides efficiency gains and overcomes the issues GMM estimators encounter in the estimation of long-run effects when the coefficient on the lagged dependent variable is close to one.

Effects of hypertonic saline versus mannitol in patients with traumatic brain injury in prehospital, emergency department, and intensive care unit settings: a systematic review and meta-analysis

BackgroundIntracranial pressure control has long been recognized as an important requirement for patients with severe traumatic brain injury. Hypertonic saline has drawn attention as an alternative to mannitol in this setting. The aim of this study was to assess the effects of hypertonic saline versus mannitol on clinical outcomes in patients with traumatic brain injury in prehospital, emergency department, and intensive care unit settings by systematically reviewing the literature and synthesizing the evidence from randomized controlled trials.MethodsWe searched the MEDLINE database, the Cochrane Central Register of Controlled Trials, and the Igaku Chuo Zasshi (ICHUSHI) Web database with no date restrictions. We selected randomized controlled trials in which the clinical outcomes of adult patients with traumatic brain injury were compared between hypertonic saline and mannitol strategies. Two investigators independently screened the search results and conducted the data extraction. The primary outcome was all-cause mortality. The secondary outcomes were 90-day and 180-day mortality, good neurological outcomes, reduction in intracranial pressure, and serum sodium level. Random effects estimators with weights calculated by the inverse variance method were used to determine the pooled risk ratios.ResultsA total of 125 patients from four randomized trials were included, and all the studies were conducted in the intensive care unit. Among 105 patients from three trials that evaluated the primary outcome, 50 patients were assigned to the hypertonic saline group and 55 patients were assigned to the mannitol group. During the observation period, death was observed for 16 patients in the hypertonic saline group (32.0%) and 21 patients in the mannitol group (38.2%). The risks were not significant between the two infusion strategies (pooled risk ratio, 0.82; 95% confidence interval, 0.49–1.37). There were also no significant differences between the two groups in the other secondary outcomes. However, the certainty of the evidence was rated very low for all outcomes.ConclusionsOur findings revealed no significant difference in the all-cause mortality rates between patients receiving hypertonic saline or mannitol to control intracranial pressure. Further investigation is warranted because we only included a limited number of studies

The impact of corporate social responsibility on stock price volatility of the US banks: a moderating role of tax

PurposeCorporate social responsibility (CSR) is considered one of the crucial branding and promotional tools for banks to legitimise their role in society to become socially and environmentally responsible corporate citizen. The purpose of this study is to investigate the effect of CSR on stock price volatility of the US banks. This study further examined the moderating role of tax on the relationship between CSR and stock price volatility.Design/methodology/approachThis study uses the random-effects panel regression estimation technique to test the hypotheses. The authors include a sample of 37 US banks from 2013 to 2017 with 144 bank-years observation. The authors consider the environmental, social and governance (ESG) scores from Refinitiv as a proxy for CSR. The financial data are also collected from the Refinitiv Datastream database.FindingsThis study finds a significant and positive relationship between CSR and stock price volatility, which indicates that shareholders of the US banks may not prefer excess concentration on CSR because of the additional cost of investment associated with implementing CSR. Also, tax payments and stock price volatility show a significant positive association, which implies that there is a higher possibility of an increase in stock price volatility if the tax rate increases. Generally, shareholders are not interested in paying more taxes, so they may swap the market instead of paying more tax. On the other hand, the authors find a non-significant moderating effect of tax payment on CSR-volatility nexus.Originality/valuePrevious studies mainly focussed on CSR and financial performance of banks. Conversely, studies focussing on CSR and stock volatility are limited. This study will fill the gap in the literature by considering the effect of CSR on the stock price volatility of the US banks.

Effects of Febuxostat on Mortality and Cardiovascular Outcomes: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

ObjectiveTo investigate the association between using febuxostat and cardiovascular events.MethodsSystematic search of randomized controlled trials was performed using PubMed/MEDLINE, Cochrane review, and EMBASE databases through April 17, 2019. Meta-analysis was performed using random effect model and estimates were reported as risk difference (RD) with 95% CIs. The certainty of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation approach. The main outcomes of interest were cardiovascular mortality and all-cause mortality.ResultsA total of 15 randomized controlled trials (16,070 participants) were included. The mean ± SD age was 58.1±11.7 years. At the median follow-up of 6.4 months, use of febuxostat was not associated with statistically significant risk of cardiovascular mortality (RD, 0.12%; 95% CI, -0.25% to 0.49%; I2=48%; low certainty evidence), all-cause mortality (RD, 0.20%; 95% CI, -0.28% to 0.68%; I2 =60%; very low certainty evidence), major adverse cardiovascular events (RD, 0.40%; 95% CI, -0.34% to 1.13%; I2=26%; low certainty evidence), myocardial infarction (RD, -0.06%; 95% CI, -0.29% to 0.17%; I2 =0%; moderate certainty evidence), stroke (RD, 0.10%; 95% CI, -0.15% to 0.35%; I2=0%; moderate certainty evidence), or new-onset hypertension (RD, 1.58%; 95% CI, -0.63% to 3.78%; I2=58%; very low certainty evidence). These findings were consistent in patients with existing cardiovascular disease.ConclusionThis meta-analysis suggested that use of febuxostat was not associated with higher risk of mortality or adverse cardiovascular outcomes in patients with gout and hyperuricemia. The results were limited by low to moderate certainty of evidence.

The nexus between capital structure, firm-specific factors, macroeconomic factors and financial performance in the textile sector of Pakistan

The study aimed to analyse the role of the capital structure in the financial performance of 90 textile firms listed in Pakistan Stock Exchange (PSX) during the period 2008–2017. The dependent variable was return on equity as a proxy for financial performance. The independent variables were the debt to equity, total debt to total assets, asset turnover ratios, sales growth, taxation, and export growth, while the firm size was taken as a control variable. The panel regression estimation technique was employed for analysis purposes, and both cross-sectional and time-series data were collected for this study. This study used the random-effect regression estimation model based on the Hausman diagnostic test statistics. The results indicate that the capital structure debt to equity variable has a negative and significant relationship with financial performance while the asset turnover ratio and firm performance showed a negative and statistically insignificant relationship. Export growth and sales growth have a considerable positive connection with financial performance; however, firm size has a negative and significant impact on firm performance, in favour of our alternative research hypothesis. The remaining variables include tax payable and the total debt to total assets ratio, which have an insignificant connection with financial performance (ROE) and validate the agency theory. With better corporate governance by putting more pressure on managers or increasing managerial ownership, institutional investors can reduce the capital, leverage risk and the overall firm capital cost that help to improve the firm's financial performance and economic stability.