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This paper considers problems of interval estimation and hypotheses testing for the generalized Lorenz curve under the Pareto distribution. Our approach is based on the concepts of generalized test variables and generalized pivotal quantities. The merits of the proposed procedures are numerically carried out and compared with asymptotic and bootstrap methods. Empirical evidence shows that the coverage accuracy of the proposed confidence intervals and the type I error control of the proposed exact tests are satisfactory. For illustration purposes, a real data set on median income of the 20 occupations in the United States Census of Population is analysed. [ABSTRACT FROM PUBLISHER]

Inverse Weibull (IW) distribution is one of the widely used probability distributions for nonnegative data modelling, specifically, for describing degradation phenomena of mechanical components. In this paper, by compounding IW and power series distributions we introduce a new lifetime distribution. The compounding procedure follows the same set-up carried out by Adamidis and Loukas [A lifetime distribution with decreasing failure rate. Stat Probab Lett. 1998;39:35–42]. We provide mathematical properties of this new distribution such as moments, estimation by maximum likelihood with censored data, inference for a large sample and the EM algorithm to determine the maximum likelihood estimates of the parameters. Furthermore, we characterize the proposed distributions using a simple relationship between two truncated moments and maximum entropy principle under suitable constraints. Finally, to show the flexibility of this type of distributions, we demonstrate applications of two real data sets. [ABSTRACT FROM PUBLISHER]

Migraine is a chronic neurological disease described by recurrent moderate to severe headaches often in association with neuro-inflammation. As cytokines are affect the immune response and migraine exacerbation, the current study aimed to investigate the possible associations between CD40 polymorphisms and level of soluble CD154 protein with migraine. In a prospective case-control study, we studied blood samples of 190 patients with migraine (migraineurs) and 200 healthy controls (HCs) from southeast Iran. Genotyping for the CD40 (rs4810485-intron, rs1883832-5´-UTR, and rs3765459-intron) gene variants were executed using PCR-RFLP and soluble CD154 protein levels were measured via ELISA method. Among CD40 gene variants, rs1883832 (TC genotype) was significantly associated with migraine (P = 0.007, OR = 2.326, 95% CI = 1.258-4.303).  No significant associations observed between the rs4810485 and rs3765459 SNPs with migraine. The most frequent genotypes for CD40 were GG in rs4810485 (51.5%) and rs3765459 (62.1%) as well as TC in rs1883832 (53.7%). There was no statistically relationship between these gene variants and different subclasses of migraine. Concentration of soluble CD40L among patients with rs1883832 (TC genotype) were significantly (P = 0.027, OR = 0.417, CI = 0.192-0.906) higher in compared to healthy controls. Our findings showed that in CD40 rs1883832, TC genotype may have a role in migraine susceptibility. Therefore, it suggested that in addition to other factors, CD40 rs1883832 (TC genotype) genetic variation may also play a critical role in the etiology of migraine.