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Bogna Zawieja, Sylwia Lewandowska, Tomasz Mikulski and Wiesław Pilarczyk

Summary

An analysis is made of results from early stages of testing of promising hybrids. The data consist of single-replicate trials performed by Norddeutsche Pflanzenzucht in 6 locations (5 in Poland and one in Germany). In total 165 hybrids were tested with 3 standard varieties. The subject of the analysis was the seed yield. Three measures of stability were used. The yield of tested hybrids is expressed as percentage of that of standard varieties. Wricke’s ecovalence expressed as a contribution to G x E interaction was used as a measure of stability. Additional characterization of the tested hybrids was performed by regressing hybrid yield on the mean yields of the experiment, as described by Finlay and Wilkinson and by Eberhart and Russel. The methods applied enabled selection of the most promising hybrids for further yield testing.

Open access

Moawia Alghalith

Summary

We develop a simple method that completely eliminates the specification error and spurious relationships in regression. Furthermore, we introduce a stronger test of causality. We apply our method to oil prices.

Open access

Iwona Mejza, Katarzyna Ambroży-Deręgowska, Jan Bocianowski, Józef Błażewicz, Marek Liszewski, Kamila Nowosad and Dariusz Zalewski

Summary

The main purpose of this study was the model fitting of data deriving from a three-year experiment with barley malt. Two linear models were considered: a fixed linear model with fixed effects of years and other factors, and a mixed linear model with random effects of years and fixed effects of other factors. Two cultivars of brewing barley, Sebastian and Mauritia, six methods of nitrogen fertilization and four germination times were analyzed. Three quantitative traits were observed: practical extractivity of the malt, malting productivity, and a quality coefficient Q. The starting point for the statistical analyses was the available experimental material, which consisted of barley grain samples destined for malting. The analyses were performed over a series of years with respect to fixed or random effects of years. Due to the strong differentiation of the years of the study and some significant interactions of factors with years, annual analyses were also carried out.

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Kiyotaka Iki, Hiroshi Nakano and Sadao Tomizawa

Summary

For square contingency tables with ordered categories, Iki, Tahata and Tomizawa (2012) considered a measure to represent the degree of departure from marginal homogeneity. However, the maximum value of this measure cannot distinguish two kinds of marginal inhomogeneity. The present paper proposes a measure which can distinguish two kinds of marginal inhomogeneity. In particular, the proposed measure is useful for representing the degree of departure from marginal homogeneity when the marginal cumulative logistic model holds.

Open access

Abimbola A. Akanni, Idowu Omisile and Choja A. Oduaran

Abstract

Workplace deviant behavior has been linked to a number of organizational losses such as decreased employee morale, increased turnover and loss of legitimacy among important external stakeholders. Therefore, this paper investigated the relationships between religiosity, job status and workplace deviant behavior. Participants consisted of 351 (F=178; Mean age=39.2) employees of the Local Government Service Commission in Nigeria. Data which were sourced through the Workplace Deviant Behavior Scale and Centrality of Religiosity Scale were analyzed using multiple regression. Results revealed that religiosity negatively related to workplace deviant behavior, but no significant difference was found between junior and senior staff in their display of workplace deviant behavior. In addition, both religiosity and job status jointly influenced respondents’ workplace deviant behavior. The findings imply that high religiosity among employees might reduce the risks of deviance and in turn create a better work environment.

Open access

Vasile Gherheş

Abstract

The study presents the results regarding the attitudes of students from humanities and technical specializations in Timișoara towards the emergence and development of artificial intelligence (AI). The emphasis was on the most likely consequences of the development of artificial intelligence in the future, especially the negative consequences that its development would entail. The method used for data collection was the sociological survey and the information gathering tool was the questionnaire. It was applied to a total of 929 people, ensuring a sample representativity margin of ± 3%. The analysis reveals that the participants in the study predict that due to the emergence and development of AI, in the future, interpersonal relationships will be negatively affected, there will be fewer jobs, economic crises will emerge, it will be used to make intelligent weapons, to increase military conflicts, to take control of humanity and, last but not least, to destroy mankind. The results revealed differences in responses depending on the type of specialization (humanities or technical) and the gender of the respondents.

Open access

M. Iwańska, A. Oleksy, M. Dacko, B. Skowera, T. Oleksiak and E. Wójcik-Gront

Summary

Wheat is one of the modern world’s staple food sources. Its production requires good environmental conditions, which are not always available. However, agricultural practices may mitigate the effects of unfavorable weather or poor-quality soils. The influence of environmental and crop management variables on yield can be evaluated only based on representative long-term data collected on farms through well-prepared surveys.The authors of this work analyzed variation in winter wheat yield among 3868 fields in western and eastern Poland for 12 years, as dependent on both soil/weather and crop management factors, using the classification and regression tree (CART) method. The most important crop management deficiencies which may cause low wheat yields are insufficient use of fungicides, phosphorus deficiency, non-optimal date of sowing, poor quality of seeds, failure to apply herbicides, lack of crop rotation, and use of cultivars of unknown origin not suitable for the region. Environmental variables of great importance for the obtaining of high yields include large farm size (10 ha or larger) and good-quality soils with stable pH. This study makes it possible to propose strategies supporting more effective winter wheat production based on the identification of characteristics that are crucial for wheat cultivation in a given region.

Open access

Ravi Shanker Dubey, Anil Sharma and Monika Jain

Abstract

Elliptic-type integral plays a major role in the study of different problems of physics and technology including fracture mechanics. Many papers have been written for various families of elliptic-type integrals. Due to their applications here, we are presenting an organized study of certain generalized family of incomplete elliptic integral. The obtained results are basic in nature have various generalizations. While using the fractional integral operator of Riemann-Liouville type, we found several obvious hyper geometric representations. Which are further used to originate many definite integrals relating to their modules and amplitude of elliptic type generalized incomplete integrals.

Open access

Jonathan Gessendorfer, Jonas Beste, Jörg Drechsler and Joseph W. Sakshaug

Abstract

Record linkage has become an important tool for increasing research opportunities in the social sciences. Surveys that perform record linkage to administrative records are often required to obtain informed consent from respondents prior to linkage. A major concern is that nonconsent could introduce biases in analyses based on the linked data. One straightforward strategy to overcome the missing data problem created by nonconsent is to match nonconsenters with statistically similar units in the target administrative database. To assess the effectiveness of statistical matching in this context, we use data from two German panel surveys that have been linked to an administrative database of the German Federal Employment Agency. We evaluate the statistical matching procedure under various artificial nonconsent scenarios and show that the method can be effective in reducing nonconsent biases in marginal distributions, but that biases in multivariate estimates can sometimes be worsened. We discuss the implications of these findings for survey practice and elaborate on some of the practical challenges of implementing the statistical matching procedure in the context of linkage nonconsent. The developed simulation design can act as a roadmap for other statistical agencies considering the proposed approach for their data.

Open access

Nuri Celik

Abstract

In this article, we introduce some examples of cubic rank transmuted distributions proposed by Granzatto et al. (2017). The statistical aspects of the introduced distributions such as probability density functions, hazard rate functions and reliability functions are studied. The maximum likelihood estimation method is used in order to estimate the parameters of interest. Finally, real data examples are applied for the illustration of these distributions.