Quantile estimation and comparing two independent groups with an approach based on percentile bootstrap

Although the most common approach for comparing two independent groups is on the basis of some measure of location, determination of the differences in the tails of the groups is often of interest. In this study, Harrell–Davis estimator, Sfakianakis–Verginis estimators and default quantile estimator of R are used in conjunction with a percentile bootstrap method with the aim of comparing two independent groups via the quantiles, and the relative efficiencies of Harrell–Davis and Sfakianakis–Verginis estimators are compared. General performance of Sfakianakis–Verginis estimators was much better than Harrell–Davis estimator in terms of both saving actual type I error and relative efficiency.     

Radon as a Tracer of Lung Changes Induced by Smoking

After smoking, exposure to radon and its progeny is the second leading cause of lung cancer. The probability of inducing lung carcinomas by inhaled radon progeny depends on the deposited radiation dose, and is significantly affected by physiological and morphometric changes induced by smoking. Due to irritation of the airways, the inhalation of cigarette smoke leads to the hyperproduction of mucus. Two concurrent processes occur: on one hand, increased production of mucus protects the target cells against radiation damage; on the other hand, in the case of long-term smokers, a chronic lung obstruction develops, causing an increase in the radiation dose to the lungs. Depending on the duration and intensity of smoking, these processes contribute to the final radiation dose with different weights. The primary objective of this study was to investigate to what extent these smoke-induced changes can modify the resulting absorbed dose of inhaled radon progeny relative to healthy nonsmokers. Since the bronchial dose depends on the degree of lung tissue damage, we have used this dose as a tool for detecting the effects of smoking on the lung epithelium. In other words, the biological effect of radon served as a tracer of changes induced by smoking.     

Supply chain relationship quality and its impact on firm performance

Abstract

This paper examines the impact of supply chain relationship quality (SCRQ) on firm performance (FP) through the mediators of supply chain management processes (SCMP) and supply chain performance (SCP). In the literature, these linkages have been examined separately; in contrast, this study takes a holistic perspective on the antecedents of FP. The model was tested using survey data from manufacturing companies. Variance-based structural equation modelling revealed that both SCMP and SCP lead to FP, unlike SCRQ. On the other hand, SCRQ affects SCMP. Drawing on the resource-based view, consistency in SCRQ can lead to not only efficient and effective supply chain management but also improvements in FP and SCP. This research has practical implications, providing supply chain decision makers with insights on enhancing FP. Supply chain decision makers will be able to benefit from the findings of our study by improving supply chain relationships with supply chain members and ensuring FP. This research also highlights how effective management of SCRQ, SCMP and SCP can provide better FP and a competitive advantage.     

Separating trend and cyclical dynamics in state space models with exogenous inputs

In the present study we compare three state rotation methods in modelling the impact of the US economy on the Finnish economy, i.e. Schur decomposition, eigenvalue analysis and singular value decomposition. Singular value decomposition is seen to provide a robust approximation of the state rotation in most cases studied, irrespective of whether the characteristic roots of the state transition matrix are complex. Thus, singular value decomposition seems to be a viable computational device not only in estimating the system matrices of the state space model, but also in state rotation, as compared to the more involved techniques based on eigenvalue analysis or Schur decomposition.     

Evaluation of Early Adolescent Subjective Well-Being in Terms of Submissive Behavior and Self-Esteem

This research aimed to investigate the correlation between subjective well-being and submissive behavior and self-esteem in students in the early adolescent period. The research was completed with a relational design. The research group comprised sixth, seventh, and eighth class middle school students in the spring term of the 2015–2016 academic year in Trabzon province. Data collection tools included a Personal Information Form, Submissive Behavior Scale, Two-Dimensional Self-Respect Scale (Self-Liking and Self-Confidence Scale), Satisfaction with Life Scale and Positive and Negative Affect Schedule. The results of the correlation analysis found a significant positive correlation between subjective well-being and self-esteem (r?=?0.54, p?<?0.01; 95% CI [0.44, 0.61], Cohen’s d?=?1.28); however, the correlation between subjective well-being and submissive behavior was not significant (r?=?–0.02, p?>?0.05; 95% CI [–0.11, 0.09], Cohen’s d?=?0.04). There was a significant negative correlation identified between self-esteem and submissive behavior (r?=?–0.10, p < 0.05; 95% CI [–0.20, –0.01], Cohen’s d?=?–0.20). Additionally, according to our findings, self-esteem accounts for 29% of the variation in well-being (F(1, 367)?=?150.79, p?<?0.001). The contribution of self-esteem to the subjective well-being explanatory model was found to be significant (sz?=?0.54, p?<?0.001).     

Restricted ridge estimator in generalized linear models: Monte Carlo simulation studies on Poisson and binomial distributed responses

It is known that collinearity among the explanatory variables in generalized linear models (GLMs) inflates the variance of maximum likelihood estimators. To overcome multicollinearity in GLMs, ordinary ridge estimator and restricted estimator were proposed. In this study, a restricted ridge estimator is introduced by unifying the ordinary ridge estimator and the restricted estimator in GLMs and its mean squared error (MSE) properties are discussed. The MSE comparisons are done in the context of first-order approximated estimators. The results are illustrated by a numerical example and two simulation studies are conducted with Poisson and binomial responses.     

Anti-Afropolitan ethics and the performative politics of online scambaiting

ABSTRACT

Online scambaiting problematises the identity of the 419 scammer whose virtual labours connect significantly to the digital dimensions of Afropolitanism. When examined through the photographic practices demanded of 419 scammers in several Internet communities, scambaiting, a form of Internet vigilantism that is targeted at online scammers to avert scam, produces epistemic violence which evacuates the black male body of human dignity. Although scambaiting is potentially an ethical project, it embeds a system of oppression that generates Afropolitan masculinities, caricatured performances of the bodies of 419 scammers exhibited online as objects of shame. As a philosophical and aesthetic response to translocality and mobility, Afropolitanism stresses the cultural experiences and agency of ordinary Africans who assert a global sense of awareness. As both the Afropolitan subject and the 419 scammer are entangled in the assertion of agency, the globalism of both is shown to converge at the intersection of the digital. Building on Lisa Nakamura's essay on dogshaming, I argue that the sexual exploitation of black bodies on scambaiting websites gestures at technology's complicity in interpellating digital subjects and circulating social injustices. Unlike Nakamura, I foreground the performative aspects of scambaiting and connect these to Afropolitanism's intrinsic digitality.