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Kozakoznawstwo jako nurt naukowy – perspektywy, stan i możliwości

Author(s): Daria Ławrynow / Language(s): Polish Issue: 2/2021

The article presents various methodological approaches to the Cossacks Studies with a special focus on the past and present academic discourses and practices in Ukraine, the Russian Federation, the Republic of Kazakhstan and Poland. Images of Cossack armies provide an interesting but hybrid research material, because these military groups represent both the identity of the border communities and the military democratic society. Hence the exceptionally varied ways of viewing their identity in which this group has been seen as a nation, ethnic group, Asian Orda or Russian//Ukrainian military nobility. In contemporary Ukrainian science, the Cossacks have been perceived as a leading force behind the nation-building process, while for the Russian researchers, they have been depicted as local insurgents. In Polish science and discourse, the Cossacks are analyzed strictly from the Polish historical perspective. The article suggests that those diversified approaches to the Cossack identity and history may help formulating a comprehensive and universal discourse and methodology for the Cossacks Studies.

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БІБЛІОГРАФІЧНА ЕВРИСТИКА ТА БІБЛІОГРАФІЧНИЙ ПОШУК: КОРЕЛЯЦІЯ СУТНОСТІ ПОНЯТЬ

Author(s): Oksana Zbanatska / Language(s): Ukrainian Issue: 4/2020

The purpose of the article is to identify the essence of the concepts «bibliographical heuristics» and «bibliographical search», to discover the relationship between them. The methodology is based on the use of scientific analysis, synthesis, comparison methods, that allowed us to identify, investigate and compare the essence of the proposed concepts. The use of a structural approach made it possible to build a communication environment of bibliographical heuristics. The scientific novelty of the work consists of the correlation of the concepts’ essence «bibliographical heuristics» and «bibliographical search»; the definition of the communication environment of bibliographical heuristics. Conclusions. The concepts of bibliographical heuristics and bibliographical search are correlated as a science and an object of study of the science. Bibliographical heuristics is the science of theory and practice of bibliographical search. Bibliographical heuristics develop rules, determines the search strategy depending on the type of search query, the criteria for issuing search results, and the nature of the dialogue between the user and the information search engine. It is the theoretical basis of bibliographical search. The object of bibliographical heuristics is bibliographical search as the process of bibliographical activity associated with the search for bibliographical information, enhanced by intuition, logic, experience, which depends on the specific situation and tasks of the search. The main components of bibliographical search are bibliographical finding and identifying. Bibliographical search is a clarification of bibliographical records, an identification of missing elements in them, a correction of errors distorted in the query. Bibliographical identifying is an exhaustive selection of bibliographical records on a particular topic. Bibliographical heuristics and bibliographical search exist in a certain communication environment that accumulates and disseminates bibliographical knowledge.

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On the generalisation of Quatember’s bootstrap

Author(s): Tomasz Żądło / Language(s): English Issue: 1/2021

The problem of the estimation of the design-variance and the design-MSE of different estimators and predictors is considered. Bootstrap algorithms applicable to complex sampling designs are used. A generalisation of the bootstrap procedure studied by Quatember (2014) is proposed. In most of the cases considered in our simulation study it leads to more accurate estimates (or to very similar ones in remaining cases) of the design-MSE and the design-variance compared with the original algorithm and its other counteparts.

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Interviewer allocation through interview–reinterview nested design for response error estimation in sample surveys

Author(s): Fidan Mahmut Fahmi,H. Öztaş Ayhan,İnci Batmaz / Language(s): English Issue: 2/2021

In surveys, non-sampling errors, due to their complex nature, are more challenging to quantify compared to sampling errors. Avoiding the release of these errors, however, results in biased survey estimates. In our previous paper, we devised the best interviewer allocation technique by using a nested experimental design to study response error estimation. In this study, in order to illustrate the effectiveness of this methodology in a different context, we apply it in interview-reinterview surveys relating to the time use and life satisfaction of academicians at Middle East Technical University, Turkey. An analysis of the pilot survey data showed that only half of the data was reliable, while the other half revealed interviewer effects. Prior to the main survey, interviewers underwent training in the course of which particular emphasis was put on the above-mentioned questions. In effect, the previously observed response variances which accounted for the total variance and data unreliability, were reduced considerably, increasing the quality of the main survey.

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Developing calibration estimators for population mean using robust measures of dispersion under stratified random sampling

Author(s): Ahmed Audu,Rajesh Singh,Supriya Khare / Language(s): English Issue: 2/2021

In this paper, two modified, design-based calibration ratio-type estimators are presented. The suggested estimators were developed under stratified random sampling using information on an auxiliary variable in the form of robust statistical measures, including Gini’s mean difference, Downton’s method and probability weighted moments. The properties (biases and MSEs) of the proposed estimators are studied up to the terms of firstorder approximation by means of Taylor’s Series approximation. The theoretical results were supported by a simulation study conducted on four bivariate populations and generated using normal, chi-square, exponential and gamma populations. The results of the study indicate that the proposed calibration scheme is more precise than any of the others considered in this paper.

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A comparative study of a class of direct estimators for domain mean with a direct ratio estimator for domain mean using auxiliary character

Author(s): Brij Behari Khare,Kumar Ashutosh Ashutosh,Piyush Kant Rai / Language(s): English Issue: 2/2021

Estimation techniques for a domain parameter play a very significant role in the theory of sample surveys. In the recent years many advanced methodologies have been developed for domain estimation. In particular, direct and synthetic estimators are applied for the estimation of domain mean in the government and private sectors under certain assumptions as to the size of the samples relating to particular domains. The findings demonstrate that the direct estimator fails to perform more efficiently as compared to the synthetic estimator when reliable units are not directly accessible in the studied domains. Moreover, due to the fact that small units belong to the sample of the studied domain, the direct estimator produces an unacceptably large standard error. In contrast, if a sufficient number of units are available in the studied domain, the direct estimator produces effective results. This paper presents the theoretical aspects of the proposed class of direct estimators for domain mean with the use of a single auxiliary character, compared with an existing direct ratio estimator for domain mean (given in section 3.2). In addition, an empirical study has been provided to support the validity of the proposed estimators. The findings prove that the proposed estimators outperform the direct ratio estimator for domain mean using a single auxiliary character in the case of two studied populations and their analysed domains considered from Sarndal et al. (1992).

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Bayesian estimation and prediction based on Rayleigh record data with applications

Author(s): Raed R. Abu Awwad,Omar M. Bdair,Ghassan K. Abufoudeh / Language(s): English Issue: 3/2021

Based on a record sample from the Rayleigh model, we consider the problem of estimating the scale and location parameters of the model and predicting the future unobserved record data. Maximum likelihood and Bayesian approaches under different loss functions are used to estimate the model’s parameters. The Gibbs sampler and Metropolis-Hastings methods are used within the Bayesian procedures to draw the Markov Chain Monte Carlo (MCMC) samples, used in turn to compute the Bayes estimator and the point predictors of the future record data. Monte Carlo simulations are performed to study the behaviour and to compare methods obtained in this way. Two examples of real data have been analyzed to illustrate the procedures developed here.

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A new reciprocal Rayleigh extension: properties, copulas, different methods of estimation and a modified right-censored test for validation

Author(s): Haitham M. Yousof,Masoom M. Ali,Hafida Goual,Mohamed Ibrahim / Language(s): English Issue: 3/2021

In this article, a new reciprocal Rayleigh extension called the Xgamma reciprocal Rayleigh model is defined and studied. The relevant statistical properties are derived, and the useful results related to the convexity and concavity are addressed. We discussed the estimation of the parameters using different estimation methods such as the maximum likelihood estimation method, the ordinary least squares estimation method, the weighted least squares estimation method, the Cramer-Von-Mises estimation method, and the bootstrapping method. A simulation study was conducted to assess the performances of the proposed estimation methods are investigated through a simulation study. Many bivariate and multivariate type model have also been derived based on Farlie-Gumbel-Morgenstern copula, the Clayton copula, Renyi’s entropy copula and the Ali-Mikhail-Haq copula. A modified Nikulin-Rao-Robson test for right-censored validation is applied to a censored real data set.

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Robust Bayesian insurance premium in a collective risk model with distorted priors under the generalised Bregman loss

Author(s): Agata Boratyńska / Language(s): English Issue: 3/2021

The article presents a collective risk model for the insurance claims. The objective is to estimate a premium, which is defined as a functional specified up to unknown parameters. For this purpose, the Bayesian methodology, which combines the prior knowledge about certain unknown parameters with the knowledge in the form of a random sample, has been adopted. The generalised Bregman loss function is considered. In effect, the results can be applied to numerous loss functions, including the square-error, LINEX, weighted squareerror, Brown, entropy loss. Some uncertainty about a prior is assumed by a distorted band class of priors. The range of collective and Bayes premiums is calculated and posterior regret Γ-minimax premium as a robust procedure has been implemented. Two examples are provided to illustrate the issues considered - the first one with an unknown parameter of the Poisson distribution, and the second one with unknown parameters of distributions of the number and severity of claims.

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Unreported standard errors in meta-analysis

Author(s): Nicholas T. Longford / Language(s): English Issue: 4/2021

A study that would otherwise be eligible is commonly excluded from a meta-analysis when the standard error of its treatment-effect estimator, or the estimate of the variance of the outcomes, is not reported and cannot be recovered from the available information. This is wasteful when the estimate of the treatment effect is reported. We assess the loss of information caused by this practice and explore methods of imputation for the missing variance. The methods are illustrated on two sets of examples, one constructed specifically for illustration and another based on a published systematic review.

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Approximately optimum strata boundaries for two concomitant stratification variables under proportional allocation

Author(s): Faizan Danish,S. E. H. Rizvi / Language(s): English Issue: 4/2021

The proper choice of strata boundaries is an important factor determining the efficiency of the estimator of the considered characteristics of a population. In this article, the Cum V𝐷i( 𝑥, 𝑧) Rule (i=3,4) for obtaining approximately optimum strata boundaries has been applied, taking into account a single-study variable along with two concomitant variables serving as the basis of the stratification variables. The relative efficiency of the proposed methods has been demonstrated theoretically and empirically by comparing them to a selection of already-existing methods in a simulation study with the use of the proportional allocation method.

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Agu-Eghwerido distribution, regression model and applications

Author(s): Friday Ikechukwu Agu,Joseph Thomas Eghwerido / Language(s): English Issue: 4/2021

Modelling lifetime data with simple mathematical representations and an ease in obtaining the parameter estimate of survival models are crucial quests pursued by survival researchers. In this paper, we derived and introduced a one-parameter distribution called the Agu-Eghwerido (AGUE) distribution with its simple mathematical representation. The regression model of the AGUE distribution was also presented. Several basic properties of the new distribution, such as reliability measures, mean residual function, median, moment generating function, skewness, kurtosis, coefficient of variation, and index of dispersion, were derived. The estimation of the proposed distribution parameter was based on the maximum likelihood estimation method. The real-life applications of the distribution were illustrated using two real lifetime negatively and positively skewed data sets. The new distribution provides a better fit than the Pranav, exponential, and Lindley distributions for the data sets. The simulation results showed that the increase in parameter values decreases the mean squared error value. Similarly, the mean estimate tends towards the true parameter value as the sample sizes increase.

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A new extension of Odd Half-Cauchy Family of Distributions: properties and applications with regression modeling

Author(s): Subrata Chakraburty,Morad Alizadeh,Laba Handique,Emrah Altun,G.G. Hamedani / Language(s): English Issue: 4/2021

The paper proposes a new family of continuous distributions called the extended odd half Cauchy-G. It is based on the T −X construction of Alzaatreh et al. (2013) by considering half Cauchy distribution for T and the exponentiated G(x;ξ) as the distribution of X. Several particular cases are outlined and a number of important statistical characteristics of this family are investigated. Parameter estimation via several methods, including maximum likelihood, is discussed and followed up with simulation experiments aiming to asses their performances. Real life applications of modeling two data sets are presented to demonstrate the advantage of the proposed family of distributions over selected existing ones. Finally, a new regression model is proposed and its application in modeling data in the presence of covariates is presented.

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Type II Topp-Leone Frechet distribution: properties and applications

Author(s): Rama Shanker,Umme Habibah Rahman / Language(s): English Issue: 4/2021

The paper focuses on type II Topp-Leone Frechet distribution. Its properties including hazard rate function, reverse hazard rate function, Mills ratio, quantile function and order statistics have been studied. The maximum likelihood estimation used for estimating the parameters of the proposed distribution has been explained and expressions for the Fisher information matrix and confidence intervals have been provided. The paper discusses the applications of the distribution for modeling several datasets relating to temperature. Finally, the goodness of fit of the proposed distribution has been compared with that of the Frechet distribution.

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Record data from Kies distribution and related statistical inferences

Author(s): Nesreen M. Al-Olaimat,Husam A. Bayoud,Mohammad Z. Raqab / Language(s): English Issue: 4/2021

The Kies probability model was proposed as an alternative to the extended Weibull models as it provides a more efficient fit to some real-life data sets in comparison to the aforementioned models. The paper proposes classical and Bayesian inferences for the Kies distribution based on records. Maximum likelihood estimates are studied jointly with asymptotic and bootstrap confidence intervals. Moreover, Bayes estimates, along with credible intervals are discussed assuming squared and LINEX loss functions. The proposed estimation methods have been investigated and compared via simulation studies. A real data set has been analysed for illustrative purposes.

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Estimation of the density and cumulative distribution functions of the exponentiated Burr XII distribution

Author(s): Amal S. Hassan,Salwa M. Assar,Kareem A. Ali,Heba F. Nagy / Language(s): English Issue: 4/2021

The exponentiated Burr Type XII (EBXII) distribution has wide applications in reliability and economic studies. In this article, the estimation of the probability density function and the cumulative distribution function of EBXII distribution is considered. We examine the maximum likelihood estimator, the uniformly minimum variance unbiased estimator, the least squares estimator, the weighted least squares estimator, the maximum product spacing estimator, the Cramér–von-Mises estimator, and the Anderson–Darling estimator. We derive analytical forms for the bias and mean square error. A simulation study is performed to investigate the consistency of the suggested methods of estimation. Data relating to the wind speed and service times of aircraft windshields are used with the studied methods. The simulation studies and real data applications have revealed that the maximum likelihood estimator performs more efficiently than its remaining counterparts.

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Od tekstu do kontekstu. O praktyce upodmiotowiania w przestrzeniach twórczości naukowej – prolegomena

Author(s): Marcin Kafar,Sławomir Pasikowski / Language(s): Polish Issue: 34/2020

The article presents the practice of subjectivizing scientific creativity by referring to the role of intuition in the creation process, introspective reports and comments on spatial information processing. One of the main emphases is placed on the interaction between the author’s sense of subjectivity with the idea generated and developed by him, as well as on how the reader senses this interaction. These findings became the basis for adopting assumptions about individual and disciplinary differences in strategy and the intensity of the subjectivization of scientific texts by creators and recipients. The article was prepared in a performative and dialogical formula.

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Otvorena znanost. Kratak pregled pokreta i metodološkog značaja

Author(s): Denis Vlašiček,Ivan Flis / Language(s): Croatian Issue: 3/2021

Svatko tko radi u sustavu znanosti tijekom posljednjih se godina susreo s pojmom otvorene znanosti. Poput neke poštapalice, pozivi za otvaranjem znanosti pojavljuju se u javnim politikama, nacionalnim (npr. NWO, bez dat.) i nadnacionalnim (Glavna uprava Istraživanje i inovacija, 2019) zakladama za financiranje istraživačkog rada, uredničkim tekstovima znanstvenih časopisa u gotovo svim znanstvenim disciplinama te suvremenim sociološkim i filozofskim opisima znanosti. Ukratko, duh otvorene znanosti izišao je iz boce i proširio se znanstvenoistraživačkim institucijama i svim drugim administrativnim tijelima vezanima uz njih. O čemu je zapravo riječ kad govorimo o otvorenoj znanosti?

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Pogled prema naprijed: prethodna priopćenja u ubrzanom postupku i politika otvorene znanosti

Author(s): Tanja Vučković Juroš / Language(s): English,Croatian Issue: 3/2021

At the beginning of this year, we looked back, on fifty years of the Croatian Sociological Review. As the year is nearing its end, it is now time to look ahead. As seen from previous editors’ words, many of our concerns through the years were shared. Some, however, were tied to specific historical moments. While the current moment, of course, is shaped by the coronavirus pandemic, it is joined by many other moments of natural and social catastrophes that demand academic attention. In order to provide such attention in a timely manner, the Review is introducing a new category of fast-track research notes. In addition, it is necessary to consider the open science movement in academia – the Review is now joining this movement by formulating its first open science policy.

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Big Data-driven Algorithmic Governance in Sustainable Smart Manufacturing: Robotic Process and Cognitive Automation Technologies

Author(s): Sarah Rogers,Katarina Zvarikova / Language(s): English Issue: 20/2021

With growing evidence of big data-driven algorithmic governance in sustainable smart manufacturing, there is an essential demand for comprehending robotic process and cognitive automation technologies. In this research, prior findings were cumulated indicating that artificial intelligence integrates cutting-edge performance for automating cognitive work. We carried out a quantitative literature review of ProQuest, Scopus, and the Web of Science throughout January and April 2021, with search terms including “cognitive automation tools and technologies,” “cognitive automation algorithms,” “cognitive robotic systems,” and “artificial cognitive control systems.” As we analyzed research published between 2011 and 2021, only 214 papers met the eligibility criteria. By eliminating controversial or unclear findings (insufficient/irrelevant data), results unsubstantiated by replication, too imprecise or undetailed content, and studies having quite similar titles, we decided on 21, mainly empirical, sources. Subsequent analyses should develop on cognitively automated manufacturing systems and artificial cognitive control archi- tectures.

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