Wyniki wyszukiwania - BazEkon

1

Extended Exponentiated Power Lindley Distribution

100%

Ranjbar V., Alizadeh M., Hademani G. G.

Statistics in Transition

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2018

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19

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nr 4

621-643

In this study, we introduce a new model called the Extended Exponentiated Power Lindley distribution which extends the Lindley distribution and has increasing, bathtub and upside down shapes for the hazard rate function. It also includes the power Lindley distribution as a special case. Several statistical properties of the distribution are explored, such as the density, hazard rate, survival, quantile functions, and moments. Estimation using the maximum likelihood method and inference on a random sample from this distribution are investigated. A simulation study is performed to compare the performance of the different parameter estimates in terms of bias and mean square error. We apply a real data set to illustrate the applicability of the new model. Empirical findings show that proposed model provides better fits than other well-known extensions of Lindley distributions. (original abstract)

2

A Three-Parameter Weighted Lindley Distribution and Its Applications to Model Survival Time

100%

Shanker R., Shukla K. K., Mishra A.

Statistics in Transition

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2017

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18

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nr 2

291-310

In this paper a three-parameter weighted Lindley distribution, including Lindley distribution introduced by Lindley (1958), a two-parameter gamma distribution, a two-parameter weighted Lindley distribution introduced by Ghitany et al. (2011) and exponential distribution as special cases, has been suggested for modelling lifetime data from engineering and biomedical sciences. The structural properties of the distribution including moments, coefficient of variation, skewness, kurtosis and index of dispersion have been derived and discussed. The reliability properties, including hazard rate function and mean residual life function, have been discussed. The estimation of its parameters has been discussed using the maximum likelihood method and the applications of the distribution have been explained through some survival time data of a group of patients suffering from head and neck cancer, and the fit has been compared with a one-parameter Lindley distribution and a two-parameter weighted Lindley distribution. (original abstract)

3

Power Ishita Distribution and Its Application to Model Lifetime Data

100%

Shukla K. K., Shanker R.

Statistics in Transition

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2018

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19

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nr 1

135-148

A study on two-parameter power Ishita distribution (PID), of which Ishita distribution introduced by Shanker and Shukla (2017 a) is a special case, has been carried out and its important statistical properties including shapes of the density, moments, skewness and kurtosis measures, hazard rate function, and stochastic ordering have been discussed. The maximum likelihood estimation has been discussed for estimating its parameters. An application of the distribution has been explained with a real lifetime data from engineering, and its goodness of fit shows better fit over two-parameter power Akash distribution (PAD), two-parameter power Lindley distribution (PLD) and one-parameter Ishita, Akash, Lindley and exponential distributions. (original abstract)

4

Wnioskowanie o charakterystykach zagregowanego popytu na podstawie systemów wydatków

100%

Mazur B.

Prace Naukowe Akademii Ekonomicznej we Wrocławiu

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2003

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nr 1006 Zastosowanie statystyki i matematyki w ekonomii

108-119

Niniejszy artykuł ma na celu zestawienie potrzeb wnioskowania o wielkościach ekonomicznych z możliwościami wnioskowania statystycznego w pewnym typowym dla praktyki badań empirycznych przypadku. Kontekstu modelowego dostarczają tu statyczne systemy popytu (systemy wydatków) dla zagregownych szeregów czasowych szacowane za pomocą metody największej wiarygodności (MNW). Wybór tego typu modeli jest podyktowany ich ściśle empirycznym charakterem; rozważania będą dotyczyć MNW, ponieważ ta metoda jest najczęściej stosowana. Analiza wsparta przykładem empirycznym wykazuje daleko idące ograniczenia MNW w tym zakresie. Proponowana jest pewna przybliżona i prosta w stosowaniu metoda symulacyjna mająca przynajmniej w części uzupełnić niektóre braki wynikające ze stosowania MNW. Zastosowanie owej metody jest zilustrowane na tym samym przykładzie. Wnioski płynące z analizy zamykają artykuł. (fragment tekstu)

5

An Accuracy Analysis Comparison of Supervised Classification Methods for Mapping Land Cover Using Sentinel 2 Images in the Al-Hawizeh Marsh Area, Southern Iraq

100%

Alwan I. A., Aziz N. A.

Geomatics and Environmental Engineering

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2021

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nr 15/1

5-21

Land cover mapping of marshland areas from satellite images data is not a simple process, due to the similarity of the spectral characteristics of the land cover. This leads to challenges being encountered with some land covers classes, especially in wetlands classes. In this study, satellite images from the Sentinel 2B by ESA (European Space Agency) were used to classify the land cover of Al-Hawizeh marsh/Iraq-Iran border. Three classification methods were used aimed at comparing their accuracy, using multispectral satellite images with a spatial resolution of 10 m. The classification process was performed using three different algorithms, namely: Maximum Likelihood Classification (MLC), Artificial Neural Networks (ANN), and Support Vector Machine (SVM). The classification algorithms were carried out using ENVI 5.1 software to detect six land cover classes: deep water marsh, shallow water marsh, marsh vegetation (aquatic vegetation), urban area (built-up area), agriculture area, and barren soil. The results showed that the MLC method applied to Sentinel 2B images provides a higher overall accuracy and the kappa coefficient compared to the ANN and SVM methods. Overall accuracy values for MLC, ANN, and SVM methods were 85.32%, 70.64%, and 77.01% respectively. (original abstract)

6

New Polynomial Exponential Distribution: Properties and Applications

75%

Beghriche A., Zeghdoudi H., Raman V., Chouia S.

Statistics in Transition

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2022

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23

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nr 3

95-112

The study describes the general concept of the XLindley distribution. Forms of density and hazard rate functions are investigated. Moreover, precise formulations for several numerical properties of distributions are derived. Extreme order statistics are established using stochastic ordering, the moment method, the maximum likelihood estimation, entropies and the limiting distribution. We demonstrate the new family's adaptability by applying it to a variety of real-world datasets. (original abstract)

7

A Comparison of the Method of Moments Estimator and Maximum Likelihood Estimator for the Success Probability in the Fibonacci-Type Probability Distribution

75%

Kwon Y.

Statistics in Transition

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2022

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23

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nr 3

27-41

A Fibonacci-type probability distribution provides the probabilistic models for establishing stopping rules associated with the number of consecutive successes. It can be interpreted as a generalized version of a geometric distribution. In this article, after revisiting the Fibonaccitype probability distribution to explore its definition, moments and properties, we proposed numerical methods to obtain two estimators of the success probability: the method of moments estimator (MME) and maximum likelihood estimator (MLE). The ways both of them performed were compared in terms of the mean squared error. A numerical study demonsrated that the MLE tends to outperform the MME for most of the parameter space with various sample sizes. (original abstract)

8

Parameter Estimation of Exponentiated Exponential Distribution under Selective Ranked Set Sampling

75%

Hassan A. S., Elshaarawy R. S., Nagy H. F.

Statistics in Transition

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2022

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23

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nr 4

37-58

Partial ranked set sampling (PRSS) is a cost-effective sampling method. It is a combination of simple random sample (SRS) and ranked set sampling (RSS) designs. The PRSS method allows flexibility for the experimenter in selecting the sample when it is either difficult to rank the units within each set with full confidence or when experimental units are not available. In this article, we introduce and define the likelihood function of any probability distribution under the PRSS scheme. The performance of the maximum likelihood estimators is examined when the available data are assumed to have an exponentiated exponential (EE) distribution via some selective RSS schemes as well as SRS. The suggested ranked schemes include the PRSS, RSS, neoteric RSS (NRSS), and extreme RSS (ERSS). An intensive simulation study was conducted to compare and explore the behaviour of the proposed estimators. The study demonstrated that the maximum likelihood estimators via PRSS, NRSS, ERSS, and RSS schemes are more efficient than the corresponding estimators under SRS. A real data set is presented for illustrative purposes. (original abstract)

9

The Length-Biased Power Hazard Rate Distribution: Some Properties and Applications

75%

Mustafa A., Khan M. I.

Statistics in Transition

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2022

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23

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nr 2

1-16

In this article, the length-biased power hazard rate distribution has introduced and investigated several statistical properties. This distribution reports an extension of several probability distributions, namely: exponential, Rayleigh, Weibull, and linear hazard rate. The procedure of maximum likelihood estimation is taken for parameters. Finally, the applicability of the model is explored by three real data sets. To examine, the performance of the technique, a simulation study is extracted. (original abstract)

10

Zero-Modified Poisson-Modification of Quasi Lindley Distribution and Its Application

75%

Tharshan R., Wijekoon P.

Statistics in Transition

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2022

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23

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nr 4

113-128

The Poisson-Modification of Quasi Lindley (PMQL) distribution is a newly introduced mixed Poisson distribution for over-dispersed count data. The aim of this article is to introduce the Zero-modified PMQL (ZMPMQL) distribution as an alternative to the PMQL distribution in order to accommodate zero inflation/deflation. The method of obtaining the ZMPMQL distribution jointly with some of its important properties, namely the probability mass and distribution functions, mean, variance, index of dispersion, and quantile function are presented. Furthermore, some of its special cases are discussed. The maximum likelihood (ML) estimation method is used for the unknown parameter estimation. A simulation study is conducted in order to evaluate the asymptotic theory of the ML estimation method and to show the superiority of the ML method over the method of moments estimation. The applicability of the introduced distribution is illustrated by using a real-world data set. (original abstract)

11

Estimation of P(X ≤ Y) for Discrete Distributions with Non-Identical Support

75%

Choudhury M. M., Bhattacharya R., Maiti S. S.

Statistics in Transition

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2022

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23

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nr 3

43-64

The Uniformly Minimum Variance Unbiased (UMVU) and the Maximum Likelihood (ML) estimations of R = P(X ≤ Y) and the associated variance are considered for independent discrete random variables X and Y. Assuming a discrete uniform distribution for X and the distribution of Y as a member of the discrete one parameter exponential family of distributions, theoretical expressions of such quantities are derived. Similar expressions are obtained when X and Y interchange their roles and both variables are from the discrete uniform distribution. A simulation study is carried out to compare the estimators numerically. A real application based on demand-supply system data is provided. (original abstract)

12

Poisson Area-Biased Ailamujia Distribution and Its Applications in Environmental and Medical Sciences

75%

Aijaz A., ul Ain S. Q., Afaq A., Tripathi R.

Statistics in Transition

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2022

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23

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nr 3

167-184

In this paper, a new Poisson area-biased Ailamujia distribution has been formulated to analyse count data. It was created by combining two distributions: the Poisson and areabiased Ailamujia distributions, using the compounding technique. Several distributional properties of the formulated distribution were studied. Its ageing characteristics were determined and expressed explicitly. A variety of diagrams were used to demonstrate the characteristics of the probability mass function (pmf) and the cumulative distribution function (cdf). The parameter of the developed model was estimated by employing the maximum likelihood estimation approach. Finally, two data sets were used to demonstrate the effectiveness of the investigated distribution. (original abstract)

13

Rozpoznawanie rodzaju heteroskedastyczności składników losowych modelu ekonometrycznego z wykorzystaniem dyskryminacyjnej reguły największej wiarygodności

75%

Grześkowiak A.

Prace Naukowe Akademii Ekonomicznej we Wrocławiu. Taksonomia

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2007

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14

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nr 1169 Klasyfikacja i analiza danych - teoria i zastosowania

482-488

Stwierdzenie występowania zjawiska niejednorodności wariancji składników losowych w modelu ekonometrycznym stwarza konieczność zastosowania uogólnionej metody najmniejszych kwadratów do estymacji parametrów. Implementacja uogólnionej metody najmniejszych kwadratów wymaga znajomości elementów diagonalnych macierzy kowariancji składników losowych. W badaniach empirycznych najczęściej zachodzi sytuacja, w której badacz nie ma o nich wiedzy a priori, dlatego postuluje się przyjęcie pewnego modelu heteroskedastyczności uwarunkowanego charakterem zmian wariancji składników losowych. Problemem, którego rozwiązanie zaproponowano w niniejszej pracy, jest wybór odpowiedniego w danej sytuacji modelu. Postulowana koncepcja stanowi połączenie podejścia klasycznego, opartego na teście statystycznym, z wykorzystaniem analizy dyskryminacyjnej. W pracy zaprezentowano podstawy teoretyczne sugerowanej koncepcji i zilustrowano ją badaniem empirycznym. (fragment tekstu)

14

Bayesian Estimation of Measles Vaccination Coverage under Ranked Set Sampling

75%

Das R., Verma V., Nath D. C.

Statistics in Transition

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2017

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18

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nr 4

589-608

The present article is concerned with the problem of estimating an unknown population proportion p, say, of a certain population characteristic in a dichotomous population using the data collected through ranked set sampling (RSS) strategy. Here, it is assumed that the proportion p is not fixed but a random quantity. A Bayes estimator of p is proposed under squared error loss function assuming that the prior density of p belongs to the family of Beta distributions. The performance of the proposed RSS-based Bayes estimator is compared with that of the corresponding classical version estimator based on maximum likelihood principle. The proposed procedure is used to estimate measles vaccination coverage probability among the children of age group 12-23 months in India using the real-life epidemi-ological data from National Family Health Survey-III. (original abstract)

15

Currency Demand and MIMIC Models: Towards a Structured Hybrid Model-Based Estimation of the Shadow Economy Size

75%

Dybka P., Kowalczuk M., Olesiński B., Rozkrut M., Torój A.

Collegium of Economic Analysis SGH - Working Papers

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2017

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nr 30

48

Model-based econometric techniques of the shadow economy estimation have been increasingly popular, but a systematic approach to getting the best of their complementarities has so far been missing. We review the dominant approaches in the literature currency demand analysis (CDA) and MIMIC model and propose a novel hybrid procedure that addressess their previous critique, in particular the misspecification issues in CDA equations and the vague transformation of the latent variable obtained via MIMIC model into interpretable levels and paths of the shadow economy. Our proposal is based on a new identification scheme for the MIMIC model, referred to as 'reverse standarizaton'. It supplies the MIMIC model with the panel-structured information on the latent variable's mean and variance obtained from the CDA estimates, treating this information as given in the restricted full information maximum likelihood function. This approach allows us to avoid some controversial steps, such as choosing an externally estimated reference point for benchmarking or adopting other ad hoc identifying assumptions. We estimate the shadow economy for up to 43 countries, with the results obtained in the range of 2.8% to 29.9% of GDP. Various versions of our models remain robust as regards changes in the level of the shadow economy over time and the relative position of the analysed countries. We also find that the contribution of (a correctly specified) MIMIC model to the measurement of trends in the shadow economy is marginal as compared to the contribution of the CDA model. (original abstract)

16

A New Count Data Model Applied in the Analysis of Vaccine Adverse Events and Insurance Claims

75%

Dar S. A., Hassan A., Ahmad P. B., Wani S. A.

Statistics in Transition

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2021

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22

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nr 3

157-174

The article presents a new probability distribution, created by compounding the Poisson distribution with the weighted exponential distribution. Important mathematical and statistical properties of the distribution have been derived and discussed. The paper describes the proposed model's parameter estimation, performed by means of the maximum likelihood method. Finally, real data sets are analyzed to verify the suitability of the proposed distribution in modeling count data sets representing vaccine adverse events and insurance claims.(original abstract)

17

An Alternative to Partial Regression in Maximum Likelihood Estimation of Spatial Autoregressive Panel Data Model

75%

Olejnik A., Olejnik J.

Przegląd Statystyczny

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2017

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64

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z. 3

323-337

W niniejszej pracy wprowadzono procedurę alternatywną do procedury regresji częściowej. Opisane postępowanie może być zastosowane w przypadku estymowania parametrów modelu przestrzennego autoregresyjnego metodą największej wiarogodności. Przy pewnych założeniach dotyczących wymiaru pewnej przestrzeni niezmienniczej związanej z macierzą wag przestrzennych sformułowany jest schemat postępowania obejmujący szeroką klasę macierzy efektów stałych. W pewnych przypadkach opisana procedura może eliminować efekty stałe kosztem obniżonej liczby stopni swobody. Dodatkowo, przedstawiono własności asymptotyczne zaprezentowanego estymatora. (abstrakt oryginalny)

18

Nonparametric Versus Parametric Reasoning Based on Contingency Tables

75%

Sulewski P.

Przegląd Statystyczny

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2018

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65

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z. 3

314-349

W artykule proponowane są scenariusze generowania tablic dwudzielczych (TD) z parametrem przepływu prawdopodobieństwa i zdefiniowane są miary nieprawdziwości H0. W artykule wykorzystywane są statystyki z rodziny X2 oraz statystyka modułowa |X|. Niniejsza praca jest prostą próbą zastąpienia nieparametrycznej metody wnioskowania statystycznego metodą parametryczną. Metoda największej wiarygodności jest wykorzystana do oszacowania parametru przepływu prawdopodobieństwa. W pracy opisane są także instrukcje generowania TD za pomocą metody słupkowej. Symulacje komputerowe przeprowadzono metodami Monte Carlo. (abstrakt oryginalny)

19

Bayesian Estimation of Fertility Rates under Imperfect Age Reporting

75%

Verma V., Nath D. C., Dwivedi S. N.

Statistics in Transition

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2023

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24

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nr 2

39-57

This article outlines the application of the Bayesian method of parameter estimation to situations where the probability of age misreporting is high, leading to transfers of an individual from one age group to another. An essential requirement for Bayesian estimation is prior distribution, derived for both perfect and imperfect age reporting. As an alternative to the Bayesian methodology, a classical estimator based on the maximum likelihood principle has also been discussed. Here, the age misreporting probability matrix has been constructed using a performance indicator, which incorporates the relative performance of estimators based on age when reported correctly instead of misreporting. The initial guess of performance indicators can either be empirically or theoretically derived. The method has been illustrated by using data on Empowered Action Group (EAG) states of India from National Family Health Survey-3 (2005-2006) to estimate the total marital fertility rates. The present study reveals through both a simulation and real-life set-up that the Bayesian estimation method has been more promising and reliable in estimating fertility rates, even in situations where age misreporting is higher than in case of classical maximum likelihood estimates. (original abstract)

20

Analiza czynników wpływających na jakość powietrza w wybranych regionach Polski

75%

Parlińska M., Pomichowski P.

Problemy Drobnych Gospodarstw Rolnych

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2018

|

nr 2

83-91

W pracy dokonano analizy czynników wpływających na jakość powietrza na podstawie danych o stężeniu pyłów PM10 i warunkach pogodowych. Wykonano także krótki przegląd literatury, w którym poruszono kwestie stanu jakości powietrza w wybranych regionach Polski oraz jego przyczyny. Analiza dotyczyła następujących miast Polski dla lat: 2010-2015: Warszawa, Kraków i Gdańsk, w sąsiedztwie których leżące obszary wiejskie odczuwają także problem zanieczyszczenia powietrza. Sformułowano trzy hipotezy: sezon grzewczy ma wpływ na zanieczyszczenie powietrza, określone warunki pogodowe sprzyjają pogorszeniu się jakości powietrza i jakość powietrza uległa pogorszeniu od 2010 r. Do tego celu stworzono model liniowy i oszacowano go za pomocą metody największej wiarogodności. Wyniki potwierdziły słuszność pierwszych dwóch hipotez. Trzecia została zaprzeczona, co oznacza, że stan powietrza w kolejnych latach był lepszy w porównaniu z rokiem 2010. (abstrakt oryginalny)