fixed effects model
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2022 ◽  
Author(s):  
Yuxin Feng ◽  
Zhiru Zhou ◽  
Quanming Fei ◽  
Ying Wang

Abstract IntroductionTo evaluate the association between mobile/cellular phone use and risk of three intracranial tumors (glioma, meningioma and acoustic neuroma) based on case-control studies through pooling the published data .MethodsWe conducted a systematic literature search in databases including PubMed, EMBASE, and the Cochrane Library up to September 2021. The primary outcome was the risk of tumors by mobile/cellular phone use, which was measured by pooling each odds ratio (OR) and its 95% confidence interval (CI). The random- or fixed-effects model was applied to combine the results depending on the heterogeneity of the analysis.ResultsWe ultimately included 6 articles for glioma, 6 articles for meningioma and 8 for acoustic neuroma from 1999 to 2015 . There was no significant association between mobile/cellular phone use and risk of glioma (OR, 0.98; 95% CI, 0.81-1.17; I²=76.9%, p=0.001) and acoustic neuroma (OR, 0.98; 95% CI, 0.76-1.25; I²=60.7%, p=0.013). And no statistical significance was observed between any subgroup of duration of use and these two type of cancer. Howerver, mobile phone use was associated with decrease the risk of meningioma, especially when the time since first use was between 0-5 years (OR, 0.83; 95% CI, 0.76-0.90; I²=39.5%, p=0.142) and 5-10 years (OR, 0.83; 95% CI, 0.75-0.93; I²=32.3%, p=0.194), while the protective effect disappeared in longer term (more than 10/11 years)(OR, 0.91; 95% CI, 0.80-1.03; I²=0.0%, p=0.870). ConclusionEvidence from our study mobile/cellular phone use may decreased risk of meningioma. Further studies are needed to explore the possible influence of long-term use of mobile phone and underlying mechanism.


2022 ◽  
Vol 12 ◽  
Author(s):  
Philomin Juliana ◽  
Xinyao He ◽  
Felix Marza ◽  
Rabiul Islam ◽  
Babul Anwar ◽  
...  

Wheat blast is an emerging threat to wheat production, due to its recent migration to South Asia and Sub-Saharan Africa. Because genomic selection (GS) has emerged as a promising breeding strategy, the key objective of this study was to evaluate it for wheat blast phenotyped at precision phenotyping platforms in Quirusillas (Bolivia), Okinawa (Bolivia) and Jashore (Bangladesh) using three panels: (i) a diversity panel comprising 172 diverse spring wheat genotypes, (ii) a breeding panel comprising 248 elite breeding lines, and (iii) a full-sibs panel comprising 298 full-sibs. We evaluated two genomic prediction models (the genomic best linear unbiased prediction or GBLUP model and the Bayes B model) and compared the genomic prediction accuracies with accuracies from a fixed effects model (with selected blast-associated markers as fixed effects), a GBLUP + fixed effects model and a pedigree relationships-based model (ABLUP). On average, across all the panels and environments analyzed, the GBLUP + fixed effects model (0.63 ± 0.13) and the fixed effects model (0.62 ± 0.13) gave the highest prediction accuracies, followed by the Bayes B (0.59 ± 0.11), GBLUP (0.55 ± 0.1), and ABLUP (0.48 ± 0.06) models. The high prediction accuracies from the fixed effects model resulted from the markers tagging the 2NS translocation that had a large effect on blast in all the panels. This implies that in environments where the 2NS translocation-based blast resistance is effective, genotyping one to few markers tagging the translocation is sufficient to predict the blast response and genome-wide markers may not be needed. We also observed that marker-assisted selection (MAS) based on a few blast-associated markers outperformed GS as it selected the highest mean percentage (88.5%) of lines also selected by phenotypic selection and discarded the highest mean percentage of lines (91.8%) also discarded by phenotypic selection, across all panels. In conclusion, while this study demonstrates that MAS might be a powerful strategy to select for the 2NS translocation-based blast resistance, we emphasize that further efforts to use genomic tools to identify non-2NS translocation-based blast resistance are critical.


2022 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Yupeng Wang ◽  
Satoru Shimokawa

PurposeThis paper aims to investigate how differently the COVID-19 blockade regulations influence the prices of perishable and storable foods. The authors focus on the cases of the 2020 blockade at Hubei province and the 2021 blockade at Shijiazhuang city in China, and the authors examine how the blockade influenced the prices of Chinese cabbages (perishable) and potatoes (storable) within and around the blockade area.Design/methodology/approachThe paper employs the fixed effects model, the panel VAR (PVAR) model, and the spatial dynamic panel (SPD) model to estimate the impacts of the blockade on the food prices. It constructs the unique data set of 3-day average prices of Chinese cabbages and potatoes at main wholesale markets in China during the two urban blockade periods from January 1 to April 8 in 2020 and from January 1 to March 1 in 2021.FindingsThe results from the SPD models indicate that the price of Chinese cabbages was more vulnerable and increased by 7.1–9.8% due to the two blockades while the price of potatoes increased by 1.2–6.1%. The blockades also significantly influenced the prices in the areas adjacent to the blockade area. The SPD results demonstrate that the impacts of the blockades would be overestimated if the spatial dependence is not controlled for in the fixed effects model and the PVAR model.Research limitations/implicationsBecause the research focuses on the cases in China, the results may lack generalizability. Further research for other countries is encouraged.Originality/valueThis paper demonstrates the importance of considering food types and spatial dependence in examining the impact of the COVID-19 blockades on food prices.


2022 ◽  
Vol 11 ◽  
Author(s):  
Jiawei Zhou ◽  
Jianling Bai ◽  
Yuanping Yue ◽  
Xin Chen ◽  
Theis Lange ◽  
...  

BackgroundThis meta-analysis was designed to explore the relationship between the level of serum potassium and the treatment effect of epidermal growth factor receptor (EGFR) antagonist in advanced non-small cell lung cancer (aNSCLC).MethodsWe searched phase II/III prospective clinical trials on treatment with EGFR antagonists for aNSCLC patients. The objective response rate (ORR) and/or the disease control rate (DCR) and the incidence of hypokalemia of high grade (equal to or greater than grade 3) were summarized from all eligible trials. Heterogeneity, which was evaluated by Cochran’s Q-test and the I2 statistics, was used to determine whether a random effects model or a fixed effects model will be used to calculate pooled proportions. Subgroup analysis was performed on different interventions, line types, phases, and drug numbers.ResultsFrom 666 potentially relevant articles, 36 clinical trials with a total of 9,761 participants were included in this meta-analysis. The pooled ORR was 16.25% (95%CI = 12.45–21.19) when the incidence of hypokalemia was 0%–5%, and it increased to 34.58% (95%CI = 24.09–45.07) when the incidence of hypokalemia was greater than 5%. The pooled DCR were 56.03% (95%CI = 45.03–67.03) and 64.38% (95%CI = 48.60–80.17) when the incidence rates of hypokalemia were 0%–5% and greater than 5%, respectively. The results of the subgroup analysis were consistent with the results of the whole population, except for not first-line treatment, which may have been confounded by malnutrition or poor quality of life in long-term survival.ConclusionThe efficacy of anti-EGFR targeted therapy was positively associated with the hypokalemia incidence rate. Treatment effects on the different serum potassium strata need to be considered in future clinical trials with targeted therapy.


2022 ◽  
Vol 4 (2) ◽  
pp. p12
Author(s):  
John R. Lott, Jr ◽  
Carlisle E. Moody

Using a unique data set we link the race of police officers who kill suspects with the race of those who are killed across the United States. We have data on a total of 2,706 fatal police killings for the years 2013 to 2015. This is 1,333 more killings by police than is provided by the FBI data on justifiable police homicides. We conducted three tests of discrimination. The results of these tests are different. In the first test we find some evidence that white officers are more likely to kill a black suspect who is later found to be unarmed than they are to kill an unarmed white suspect. However, this result could not be confirmed using a fixed effects model on panel data aggregated to the city level. In the second test, we find that white police officers are no more likely to kill an unarmed black suspect than are black or Hispanic officers. The results of this test are confirmed by the panel data version of the test. The third discrimination test indicated that black suspects, whether armed or not, are no more likely to be killed by a white officer than they are to be killed by black or Hispanic officers. Similarly, Hispanic suspects are no more likely to be killed by white offices than officers of other races. These results are also confirmed by panel data analyses. We find that when there is more than one officer on the scene, unarmed black suspects are not more likely to be killed by white police officers than unarmed white suspects. This could be evidence supporting a policy of reducing the number of officers working alone. Also, we find no evidence that body cameras affect either the number of police killings or the racial composition of those killings.


Economies ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 12
Author(s):  
Mahdi Salehi ◽  
Grzegorz Zimon ◽  
Maryam Seifzadeh

The present study investigates the relationship between management characteristics (managerial entrenchment, CEO narcissism, overconfidence, board effort, real and accrual-based earnings management) and the audit report readability of listed firms. In other words, this paper seeks to answer the question of “whether management characteristics can have a favourable effect on the audit report readability or not.” The multivariate regression model is used for this study. Research hypotheses were also examined using a sample of 1004 observations on the Tehran Stock Exchange during 2012–2018 and by employing multiple regression patterns based on a panel data technique and fixed effects model. The results show a negative and significant relationship between managerial entrenchment and real and accrual-based earnings management and the audit report readability, based on the FOG index, and a positive and significant relationship between management narcissism, CEO overconfidence, and board effort and the audit report readability, based on the FOG index. Moreover, a negative and significant relationship exists between management entrenchment, CEO overconfidence, real and accrual-based earnings management, and audit report readability based on text length and Flesch indices. A positive and significant relationship was evident between CEO narcissism and board effort and audit report readability based on the same indices. Besides, research models were also examined for more confidence using other additional methods, including FE, T + 1, ABB, and GMM, which confirm the study’s preliminary results. Since the present study is the first paper to investigate such a topic in the emergent markets, it provides valuable information about intrinsic and acquisitive characteristics of management for users, analysts, and legal institutions that contribute significantly to financial statement readability.


2022 ◽  
Vol 9 (1) ◽  
pp. e000603
Author(s):  
Lanlan Ji ◽  
Wenhui Xie ◽  
Serena Fasano ◽  
Zhuoli Zhang

ObjectiveGlucocorticoids (GC) withdrawal is part of the targets in current recommendations for SLE, but relapse is the most worrying issue. We aimed to investigate the predictors for flare in patients with SLE after GC withdrawal.MethodsWe systematically searched PubMed, EMBASE and Cochrane Library as well as Scopus databases up to 9 July 2021 for studies concerning predictive factors of relapses in patients with SLE after GC cessation. Pooled OR and 95% CI were combined using a random-effects or fixed-effects model.Results635 patients with SLE with GC discontinuation in 9 publications were eligible for the final analysis. Of them, 99.5% patients were in clinical remission before GC withdrawal. Serologically active yet clinically quiescent (SACQ) was associated with an increased risk of flare after GC withdrawal (OR 1.78, 95% CI (1.00 to 3.15)). Older age and concomitant use of hydroxychloroquine (HCQ) trended towards decreased risk of flare (weighted mean difference (WMD) −2.04, 95% CI (−4.15 to 0.06) for age and OR 0.50, 95% CI (0.23 to 1.07) for HCQ), yet not statistically significant. No significant association was observed regarding gender (pooled OR 1.75; 95% CI (0.59 to 5.20)), disease duration (WMD −11.91, 95% CI (−27.73 to 3.91)), remission duration (WMD −8.55, 95% CI (−33.33 to 16.23)), GC treatment duration (WMD −10.10, 95% CI (−64.09 to 43.88)), concomitant use of immunosuppressant (OR 0.86, 95% CI (0.48 to 1.53)).ConclusionYounger age and SACQ were potential risk factors of SLE flare among patients who discontinued GC. HCQ, but not immunosuppressant might prevent flare. GC withdrawal should be done with caution in this subgroup of patients.


Author(s):  
Н.Н. Дубенок ◽  
В.В. Кузьмичев ◽  
А.В. Лебедев

Основными исходными данными для определения запаса служат результаты обмеров диаметров и высот деревьев. Но обмеры диаметров деревьев на высоте груди выполнить намного проще, чем обмеры высот, поэтому ограничиваются замерами высот 15–25 деревьев. Цель исследования – по материалам измерения модельных деревьев в сосновых древостоях выбрать наиболее адекватную простую модель, которая передает зависимость между высотой деревьев и диаметром на высоте груди. Объектом исследования послужили сосновые древостои искусственного происхождения на постоянных пробных площадях в Лесной опытной даче Российского государственного агарного университета – МСХА имени К.А. Тимирязева. В работе используются данные обмеров деревьев на 17 постоянных пробных площадях с 1934 по 2005 гг. Возраст древостоев на момент проведения измерений от 50 до 125 лет. По итогам проведения 77 перечетов массив данных составил 1157 наблюдений. И модель фиксированных эффектов, и модель смешанных эффектов адекватно описали зависимость между высотами и диаметрами деревьев в культурах сосны. Но, как и ожидалось, первая модель имеет худшие значения метрик качества по сравнению со второй. Модель со смешанными эффектами более точно предсказывает значения высот по сравнению с моделью фиксированных эффектов. Недостающие значения высот большого количества деревьев на участке можно вычислить более точно с помощью модели смешанных эффектов, а не применения модели фиксированных эффектов или использования только фиксированной части (средний отклик) модели смешанных эффектов. Применение разработанной модели должно ограничиваться только в тех условиях, к которым относятся экспериментальные материалы The main data for the stock of research results is the diameter of measurements and heights of trees. But measurements of the diameter at breast height are much easier to perform than measurements of heights, therefore, they are limited to measuring the heights of 15–25 trees. The aim of the study is to select the most adequate simple model based on the measurements of model trees in pine antiquities, which conveys the relationship between the height of trees and the diameter at breast height. The object of the study was pine stands of artificial origin on permanent test plots in the Forest Experimental Station Russian State Agararian University – Moscow Timiriazev Agricultural Academy. The work uses data from tree measurements on 17 permanent sample plots from 1934 to 2005. The age of the stands at the time of measurements was from 50 to 125 years. As a result of 77 enumerations, the data array amounted to 1157 observations. Both the fixed effects model and the mixed effects model adequately describe the relationship between heights and diameters of trees in pine stumps. But, as expected, the first model has worse quality metrics than the second. The mixed effects model more accurately predicts heights from the fixed effects model. The missing heights of a large number of trees on a site can be calculated accurately using mixed effects models, rather than using fixed effects models or using only a fixed portion (mean response) of the mixed effects model. The application of the developed model should be limited only in those conditions to which the experimental materials are applied.


2021 ◽  
Author(s):  
Qi Lumin ◽  
Gu Ziying ◽  
Sun Xincheng

Abstract Background The etiology of retinopathy of prematurity (ROP) is thought to be related to genetic susceptibility and environmental exposure factors. The purpose of this article was to estimate the prevalence of ROP in mainland China and to attempt to summarize the environmental risk factors for ROP in Chinese infants. Method We searched 9 databases for articles that were published before May 29, 2021, and studies describing the prevalence and risk factors for ROP in Chinese infants were included. The fixed-effects model and the random-effects model were applied to the effect sizes (ES) and their 95% confidence intervals (CIs) with I2≤50% and I2>50% in the heterogeneity tests, respectively. Results Twenty-two separate populations were included in the meta-analysis of the prevalence of ROP. The prevalence of ROP in mainland China was 9.284% (95% CI: 6.546-12.022%). It was negatively correlated with birth weight (BW) and gestational age (GA). Fifty independent meta-analyses were observed to be related to environmental exposure factors of ROP. Thirty of the 50 meta-analyses had results that were significant at p values less than 0.05. The first three risk factors with the largest combined effect size were GA≤34 w, bronchopulmonary dysplasia (BPD) and BW≤2,000 g. Conclusions Approximately one in ten immature infants suffered from ROP. More studies need to be included. Premature babies with diseases that cause hypoxia and irregular oxygen use should be paid more attention for ROP screening.


2021 ◽  
Vol 66 (6) ◽  
pp. 52-63
Author(s):  
Nguyễn Thành Đạt

Nghiên cứu này nhằm đánh giá ảnh hưởng của tăng trưởng cho vay bất thường đối với rủi ro của ngân hàng Việt Nam, sử dụng dữ liệu bảng cân bằng, bao gồm 390 quan sát của 30 ngân hàng từ năm 2007 đến năm 2019. Bằng phương pháp hồi quy gộp (Pooled OLS), mô hình hiệu ứng cố định (Fixed effects model), mô hình hiệu ứng ngẫu nhiên (Random effects model) và phương pháp GMM (Generalized method of moments. Kết quả cho thấy, tăng trưởng cho vay bất thường bước đầu đã giúp các ngân hàng giảm bớt rủi ro. Tuy nhiên, mối quan hệ này là hình phi tuyến tính và không đồng nhất. Kết quả cho thấy, việc theo đuổi cho vay quá nhiều có nhiều khả năng dẫn đến việc ngân hàng phải chấp nhận rủi ro lớn hơn. Từ kết quả nghiên cứu bài viết đưa ra một số gợi ý nhằm hạn chế rủi ro ngân hàng đó là việc theo đuổi cho vay quá nhiều có nhiều khả năng dẫn đến việc ngân hàng phải chấp nhận rủi ro lớn hơn.


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