A New Heteroskedastic Consistent Covariance Matrix Estimator using Deviance Measure

In this article we propose a new heteroskedastic consistent covariance matrix estimator, HC6, based on deviance measure. We have studied and compared the finite sample behavior of the new test and compared it with other this kind of estimators, HC1, HC3 and HC4m, which are used in case of leverage observations. Simulation study is conducted to study the effect of various levels of heteroskedasticity on the size and power of quasi-t test with HC estimators. Results show that the test statistic based on our new suggested estimator has better asymptotic approximation and less size distortion as compared to other estimators for small sample sizes when high level of<br />heteroskedasticity is present in data

A New Heteroskedastic Consistent Covariance Matrix Estimator using Deviance Measure

In this article we propose a new heteroskedastic consistent covariance matrix estimator, HC6, based on deviance measure. We have studied and compared the finite sample behavior of the new test and compared it with other this kind of estimators, HC1, HC3 and HC4m, which are used in case of leverage observations. Simulation study is conducted to study the effect of various levels of heteroskedasticity on the size and power of quasi-t test with HC estimators. Results show that the test statistic based on our new suggested estimator has better asymptotic approximation and less size distortion as compared to other estimators for small sample sizes when high level ofheteroskedasticity is present in data

Inference for the Unit-Gompertz distribution based on record data

Practically record values are applied in situations concerning meteorology, hydrology, and sports events. A keen interest of a sports statistician may be to predict the future record value for a specific event. There are practical situations in which the record values from the available data are lost due to specific reasons. This need for record values stimulates us to construct the probability model that predicts the future record value and provides an estimation procedure in case of censored data. In the present study, the mechanism of sample moments of lower record values using the Type-II censoring is developed by assuming that the record characteristics follow the Unit Gompertz distribution. Utilizing this mechanism, the moments of lower record values are evaluated and tabulated for the specific values of the parameters. These tabulated values are applied to estimate the location and scale parameters of the underlying distribution by the method of ordered least squares. Furthermore, the point prediction and prediction interval for future record values are produced. Finally, the methodology is applied to real-life data to explain the procedure as well as show the effectiveness of forecasting out-of-sample data through the samplemoments of the lower record values, depending on the characteristicparameters of the Unit Gompertz distribution

DNA13-07606.hcdiffs

Exome sequencing dat

Identification of Novel Variants in LTBP2 and PXDN Using Whole-Exome Sequencing in Developmental and Congenital Glaucoma.

Primary congenital glaucoma (PCG) is the most common form of glaucoma in children. PCG occurs due to the developmental defects in the trabecular meshwork and anterior chamber of the eye. The purpose of this study is to identify the causative genetic variants in three families with developmental and primary congenital glaucoma (PCG) with a recessive inheritance pattern.DNA samples were obtained from consanguineous families of Pakistani ancestry. The CYP1B1 gene was sequenced in the affected probands by conventional Sanger DNA sequencing. Whole exome sequencing (WES) was performed in DNA samples of four individuals belonging to three different CYP1B1-negative families. Variants identified by WES were validated by Sanger sequencing.WES identified potentially causative novel mutations in the latent transforming growth factor beta binding protein 2 (LTBP2) gene in two PCG families. In the first family a novel missense mutation (c.4934G>A; p.Arg1645Glu) co-segregates with the disease phenotype, and in the second family a novel frameshift mutation (c.4031_4032insA; p.Asp1345Glyfs*6) was identified. In a third family with developmental glaucoma a novel mutation (c.3496G>A; p.Gly1166Arg) was identified in the PXDN gene, which segregates with the disease.We identified three novel mutations in glaucoma families using WES; two in the LTBP2 gene and one in the PXDN gene. The results will not only enhance our current understanding of the genetic basis of glaucoma, but may also contribute to a better understanding of the diverse phenotypic consequences caused by mutations in these genes

DNA12-14956.hcdiffs

Exome sequencing dat

Data from: Identification of novel variants in LTBP2 and PXDN using whole-exome sequencing in developmental and congenital glaucoma

Background Primary congenital glaucoma (PCG) is the most common form of glaucoma in children. PCG occurs due to the developmental defects in the trabecular meshwork and anterior chamber of the eye. The purpose of this study is to identify the causative genetic variants in three families with developmental and primary congenital glaucoma (PCG) with a recessive inheritance pattern. Methods DNA samples were obtained from consanguineous families of Pakistani ancestry. The CYP1B1 gene was sequenced in the affected probands by conventional Sanger DNA sequencing. Whole exome sequencing (WES) was performed in DNA samples of four individuals belonging to three different CYP1B1-negative families. Variants identified by WES were validated by Sanger sequencing. Results WES identified potentially causative novel mutations in the latent transforming growth factor beta binding protein 2 (LTBP2) gene in two PCG families. In the first family a novel missense mutation (c.4934G>A; p.Arg1645Glu) co-segregates with the disease phenotype, and in the second family a novel frameshift mutation (c.4031_4032insA; p.Asp1345Glyfs*6) was identified. In a third family with developmental glaucoma a novel mutation (c.3496G>A; p.Gly1166Arg) was identified in the PXDN gene, which segregates with the disease. Conclusions We identified three novel mutations in glaucoma families using WES; two in the LTBP2 gene and one in the PXDN gene. The results will not only enhance our current understanding of the genetic basis of glaucoma, but may also contribute to a better understanding of the diverse phenotypic consequences caused by mutations in these genes

Identification of Novel Variants in <i>LTBP2</i> and <i>PXDN</i> Using Whole-Exome Sequencing in Developmental and Congenital Glaucoma - Fig 2

<p>(a) Sanger sequencing chromatograms for the carrier III:1 and affected individual IV:2 homozygous for the mutation (b) Family pedigree and segregation of a novel frameshift mutation (c.4031_4032insA; p.Asp1345Glyfs*6) in the <i>LTBP2</i> gene in a PCG family.</p