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This paper suggests several models that describe the symmetry and asymmetry structure of each subdimension for the multiway square contingency table with ordered categories. A classical three-way categorical example is examined to illustrate the model results. These models analyze the subsymmetric and asymetric structure of the table.

In this study, a Generalized, Multi-Stage Adjusted, Latent Class Linear Mixed Model is proposed for modeling the heterogeneous distributed phenotype and genetic information across the whole genome in the presence of both serial and familial correlations. Genome data were analyzed by applying the proposed model to Genetic Analysis Workshop (GAW) data, and the model results were compared to the results of standard models. Moreover, the potential of the model is discussed compared to simulated data. As a result of model comparisons, the information criteria and the genomic control parameter were found to be smaller. The results of a power analysis show that the proposed model is more powerful. [ABSTRACT FROM AUTHOR]

A linear mixed model (LMM) is an extension of linear regression model to include both fixed effects and random effects. Recently, LMMs have been widely used especially for the analysis of longitudinal data taken from same subjects over time. The LMM can analyze the relationship between a dependent variable and two or more independent variables by taking into account subject-specific effects of nonhomogeneous subjects. Unlike previous studies, the aims of this study are to analyze the data taken at one time point by LMM and to compare LMM and multiple linear regression model in the presence of multicollinearity problem which occurs when two or more independent variables in the model are correlated with each other. We interpret the parameter estimates with application to the data set from Programme for International Student Assessment (PISA) in 2015. In this study, statistical analysis was performed for mean success scores of countries at science in PISA 2015 and data for some socioeconomic variables of countries which can be thought as factors affecting countries’ scores at science. A modeling study was conducted by taking into account of effect of multicollinearity problem. According to the findings of the study, both models have similar results without multicollinearity problem. [ABSTRACT FROM AUTHOR]

Objective: Square contingency tables that arise in dependent samples where the row and column variables have same level. Some specific models used in the analysis of these kinds of tables. These models are mostly in the symmetrical pattern. In this study, the models are introduced for two dimensional square contingency tables where the departure from the symmetry structure is observed. Models described in this paper assume ordinal categories for the contingency table. Material and Methods: Asymmetry and skew symmetry models used when the symmetry structure is distorted in analysis of square contingency tables are shown on a 280 cancer patient's dataset and the results are discussed. SPSS and SAS programs are used in the analysis of these models. The interpretations are made with the parameter estimation for the best fitting model. Results: Symmetry models do not hold for the data. While the sub models of asymmetry and skew symmetry models hold for the data, the best fitting model is determined as the uniform skew symmetry model for the cancer data. The odds ratio under uniform skew smmetry model is estimated as 1.34. Conclusion: The agreement between the cytological and pathalogical diagnosis of uterine cancer is 74% suggesting the high agreement. A cytological diagnosis recorded as suspicious is not considered as diagnostic of cancer unless supported by pathological diagnosis. As it is expected perfect agreement between the cytological classification and pathological classification in terms of accurate diagnosis, the off-diagonal cells should be studied as well. This could be done with the anaysis of square contingency tables. [ABSTRACT FROM AUTHOR]

The goal of this study is to compare the resampling methods including bootstrap and permutation tests against classical methods for paired samples. A simulation study was conducted to see the performance of both parametric and nonparametric methods under various assumptions such as non-normal populations and small or large sample sizes. The results of the simulation study are with respect to type I error and power of the test. [ABSTRACT FROM PUBLISHER]

The objective of this paper is to estimate the group-based trajectory models for longitudinal infant mortality rate data of United Nations countries. Four linear trajectories were detected. The infant mortality rate has a descending trend over the period 1990-2010 for each of the trajectories. The time varying covariate variable Human Development Index has a strong statistically significant negative linear relationship with Infant Mortality Rate. The trajectory groups were correlated with the wealth classification of the nations. [ABSTRACT FROM AUTHOR]

In this study, the sensivity of different strains of Paenibacillus larvae larvae collected from different regions of Turkey to 6 antibiotics was investigated The results showed that the level of sensivity varied. The least active antibiotics were azithromycin and tobramycin. Erythromycin was determined as an intermediate active antibiotic. Rifampin, amoxycillin clavunolic acid and sulbactam ampicillin were the most active antibiotic tested, but rifampin is used against tuberculosis, and registration of this compound for agricultural use is unlikely. [ABSTRACT FROM AUTHOR]

This study was carried out to determine the prevalence of Nosema apis (Zander) in honey bees (Apis mellifera L.) in the province of Muğla which is one of the major beekeeping areas in Turkey. 4320 worker honey bees were collected from 108 apiaries in autumn (13-15 November 2006) and spring (9-11 April 2007). They were examined in Hacettepe University Honey Bee Health Laboratory. All of the apiaries were infected with nosema. The number of spores per bee was ranged in a wide scale. According to the results, no significant difference was seen between the districts; however there was significant difference between the seasons and disease level declined in spring. In addition, the question "Is nosemosis caused the spring bee loses?" has still been discussing. [ABSTRACT FROM AUTHOR]

The evolution of SNP-SNP interactions has become an interesting field in genetic epidemiology. Most of the studies, aimed to analyze the relationship between genetic factors and disease of interest, are focused on single SNP associations. However, for quantitative traits, influenced by the interplay of environmental and more than one genetic factors, interaction between the multi factors should be taken into consideration. In this study, symmetry models for square contingency tables are applied to the cross-classified SNP-SNP interactions data. Results from a genome-wide association analysis of blood pressure are used as a prior evidence for the interacted SNPs.

Intravenous nitroglycerin (GTN) has been used as an anti-ischemic agent for the therapy of unstable and post-infarction angina. Nitric oxide (NO) and S-nitrosothiols constitute the biologically active species formed via nitroglycerin bioactivation. Increased levels of reactive oxygen species can diminish the therapeutic action of organic nitrates by scavenging donated NO and oxidizing tissue thiols important in nitrate biotransformation. Studies reported here show that the red cell activity of antioxidant enzymes, catalase and glutathione peroxidase, are significantly decreased after intravenous nitroglycerin treatment. Catalase activity (739.6 +/- 92.3 k/gHb) decreased to 440.1 +/- 111.9 and 459.8 +/- 130.7 k/gHb after 1 and 24 hr GTN infusion, respectively. Similarly, glutathione peroxidase activity (5.8 +/- 1.8 U/gHb) decreased to 3.2 +/- 1.7 and 3.8 +/- 1.1 U/g Hb after 1 and 24 hr GTN infusion, respectively. The reported decrease in antioxidant enzyme activities can lead to an oxidant milieu and contribute to the generation of nitrate tolerance.