generalized linear models
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Entropy ◽  
2022 ◽  
Vol 24 (1) ◽  
pp. 123
Author(s):  
María Jaenada ◽  
Leandro Pardo

Minimum Renyi’s pseudodistance estimators (MRPEs) enjoy good robustness properties without a significant loss of efficiency in general statistical models, and, in particular, for linear regression models (LRMs). In this line, Castilla et al. considered robust Wald-type test statistics in LRMs based on these MRPEs. In this paper, we extend the theory of MRPEs to Generalized Linear Models (GLMs) using independent and nonidentically distributed observations (INIDO). We derive asymptotic properties of the proposed estimators and analyze their influence function to asses their robustness properties. Additionally, we define robust Wald-type test statistics for testing linear hypothesis and theoretically study their asymptotic distribution, as well as their influence function. The performance of the proposed MRPEs and Wald-type test statistics are empirically examined for the Poisson Regression models through a simulation study, focusing on their robustness properties. We finally test the proposed methods in a real dataset related to the treatment of epilepsy, illustrating the superior performance of the robust MRPEs as well as Wald-type tests.


Children ◽  
2022 ◽  
Vol 9 (1) ◽  
pp. 59
Author(s):  
Massimiliano Povero ◽  
Paola Turco ◽  
Roberto Walter Dal Negro

The COVID-19 outbreak variably affected people’s mental reactions worldwide but was only episodically investigated in healthy Italian teenagers. Our aim was to investigate the emotional responses of Italian middle and high school students to the pandemic. An anonymous 10-item questionnaire was distributed in pre-selected school samples. Responders had to score their perceived extent for each reaction from 0 (lowest perception) to 10 (highest perception). A group of adults was selected as control. Generalized linear models were used to estimate differences among adults and students, high school (HS) and middle school (MS) students, and urban (U) and rural (R) MS students. Comparisons were presented as mean difference (Δ) with a 95% confidence interval (CI). A total of 1512 questionnaires (635 adults, 744 HS, 67 UMS, and 66 RMS) were analyzed. Students appeared more indifferent (Δ = 1.97, 1.52–2.41), anxious (Δ = 0.56, 0.07–1.04), aggressive (Δ = 2.21, 1.72–2.70), and depressed (Δ = 1.87, 1.40–2.34) than adults did, and claimed a higher loss of interest in their activities (Δ = 1.21, 0.72–1.70). Students were less disbelieving (Δ = −0.93, −1.50–0.35) and feared for their loved ones (Δ = −0.89, −1.40–0.39). MS students were less affected by the outbreak than HS students were. Furthermore, R-MS students were significantly less aggressive and depressed, but more indifferent and disbelieving than U-MS. Female sex was an independent factor associated to almost all the questionnaire domains. The pattern of the psychological responses to the pandemic in Italian students proved multifaceted. In addition to anxiety, loss of interest in activities, and depression, aggressiveness emerged as the most characterizing mental attitude in response to the pandemic.


Vaccines ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 52
Author(s):  
Viviana Lenis-Ballesteros ◽  
Jesús Ochoa ◽  
Doracelly Hincapié-Palacio ◽  
Alba León-Álvarez ◽  
Felipe Vargas-Restrepo ◽  
...  

We estimate the seroprevalence of IgG antibodies to varicella zoster virus (VZV) based on the first serological study in a cohort of pregnant women and newborns from the Aburrá Valley (Antioquia-Colombia) who attended delivery in eight randomly chosen hospitals. An indirect enzyme immunoassay was used to determine anti-VZV IgG antibodies. Generalized linear models were constructed to identify variables that modify seropositivity. In pregnant women, seropositivity was 85.8% (95% CI: 83.4–85.9), seronegativity was 12.6% (95% CI: 10.8–14.6), and concordance with umbilical cord titers was 90.0% (95% CI: 89–91). The seropositivity of pregnant women was lower in those who lived in rural areas (IRR: 0.4, 95% CI: 0.2–0.7), belonged to the high socioeconomic status (IRR: 0.4, 95% CI: 0.2–0.7), and had studied 11 years or more (IRR: 0.6, 95% CI: 0.4–0.8). Among newborns, seropositivity was lower in those who weighed less than 3000 g (IRR: 0.8, 95% CI: 0.6–1.0). The high seropositivity and seronegativity pattern indicates the urgent need to design preconception consultation and vaccination reinforcement for women of childbearing age according to their sociodemographic conditions, to prevent infection and complications in the mother and newborn.


2021 ◽  
Author(s):  
Kehua Chen ◽  
Guanghua Huang ◽  
Chengwei Cai ◽  
Chuangnan Yan ◽  
Fuguang Zhang ◽  
...  

Abstract Cystatin C (CysC) has been found to be associated with hemorrhagic and ischemic stroke in many studies. However, the association between CysC level and the risk of delayed cerebral ischemia after endovascular treatment of aneurysmal subarachnoid hemorrhage has been reported rarely. Our study was proposed to explore this association. Consecutive patients from June 2015 to February 2021 in this single-center retrospective study were selected. Univariate and multivariate analyses were used to identify potential prognostic risk factors for delayed cerebral ischemia, and the stability of the association was demonstrated by several statistical methods, such as subgroup analysis, interaction testing, generalized linear models, and propensity score matching. A total of 424 patients were included in the analysis. Cystatin C was independently associated with delayed cerebral ischemia. The independent effects of CysC on delayed cerebral ischemia were shown in generalized linear models with a logit link, and the results were relatively stable in crude, partial, and full models with ORs (95% CIs) for delayed cerebral ischemia. Subgroup analysis showed no significant subgroup differences in the effect of CysC on delayed cerebral ischemia. There was also no interaction effect between CysC and other confounders. Patients in the high CysC group had a higher risk of delayed cerebral ischemia than those in the low CysC group before and after propensity score matching. CysC level could be an independent predictor for the risk of delayed cerebral ischemia after endovascular treatment of aneurysmal subarachnoid hemorrhage.


Agronomy ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 2524
Author(s):  
Bao V. Q. Le ◽  
Anh Nguyen ◽  
Otto Richter ◽  
Truc T. Nguyen

Foot rot disease poses a devastating threat to pepper agriculture. In Vietnam, conventionally, fungicides are the control methods used against the disease. However, the practical effectiveness of fungicide treatment has yet to be quantitatively assessed. To fill this gap a three-factorial experiment was conducted, the factors of which were fungicide application, soil type, and infection pathway, with plant mortality and plant growth as the target variables. Two of the most common fungicides were chosen, including Agrifos 400 (potassium phosphonate) and Aliette 800WG (fosetyl-Al). The two fungicides were used in multiple treatment plans, with soil drenching selected as the means of controlling foot rot disease on red basalt soil and red basalt soil added with organic matter in a greenhouse experiment. Three-month-old pepper (Piper nigrum) plants were treated with Agrifos (application interval of 10 and 20 days), Aliette (application interval of 30 and 60 days), and a combination of both fungicides at half doses. Pepper plants were infected with the fungus Pythium spp. from soil or by direct inoculation. To assess the effect of fungicides on foot rot mortality and the growth of pepper plants, multiple generalized linear models were set up using frequentist and Bayesian approaches. Generally, both procedures suggest the same conclusions for model selection in terms of the Akaike information criterion (AIC) and the deviance information criterion (DIC). Fungicide type was found to be the main factor that affected the survival of plants. Most of the treatments (except Aliette, with an interval of 60 days) effectively reduced the mortality. The usage of fungicides affected the growth of plants in interaction with soil types. Aliette suppressed the growth of plants, especially on red soil, while Agrifos had no effect on the growth of pepper plants. The combined application of Agrifos and Aliette with half doses proves to be a promising solution for balancing cost and effectiveness in protecting plants against foot rot pathogens without affecting their growth. In our case, under the inhomogeneity of variance and unbalanced samples, the Bayesian inference appeared to be the most useful because of its flexibility in terms of model structure.


2021 ◽  
Vol 85 (4) ◽  
pp. 245-255
Author(s):  
Valéria Marques Lemos ◽  
Henrique Cabral ◽  
Stephanie Pasquaud ◽  
João Paes Vieira

The southern population of Mugil liza is distributed from Argentina (47°S) to the state of São Paulo, Brazil (23°S). Young mullets use the estuaries as nursery grounds, and prior to recruitment into estuaries they use the surf zone as a temporary habitat. Based on 12 consecutive months of sampling, this study used generalized linear models (GLM) to analyse the relationships between environmental variables and the presence and relative abundance of young mullets in the surf zone adjacent to six major estuaries in southern Brazil (between 29°S and 33°S). Young mullets were present in all seasons over the sampling period, but the probability of occurrence was higher in winter and was associated with low temperatures. The water temperature alone explained more than half of the total deviance of the GLM models for presence (23%) and abundance (21%) of young mullets in the surf zone. Site 2 (Rio Grande) had lower temperatures in the colder months, the highest probability of occurrence of all collection sites and the greatest abundance (n=3402) of young M. liza, which represented 52% of the total of individuals (n=6493) caught among the six sites sampled.


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