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Tytuł:
The Geometrical Structures of Bivariate Gamma Exponential Distributions
Autorzy:
Arwini, Khadiga Ali
Powiązania:
https://bibliotekanauki.pl/articles/1030111.pdf
Data publikacji:
2020
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Pareto distribution
bivariate distributions
bivariate gamma exponential distribution
gamma distribution
information geometry
statistical manifold
Opis:
This paper is devoted to the information geometry of the family of bivariate gamma exponential distributions, which have gamma and Pareto marginals, and discuss some of its applications. We begin by considering the parameter bivariate gamma exponential manifold as a Riemannian 3-manifold; by following Rao’s idea to use the Fisher information matrix (FIM), and derive the α-geometry as: α-connections, α-curvature tensor, α-Ricci curvature with its eigenvalues and eigenvectors, and α-scalar curvature. Where here the 0-geometry corresponds to the geometry induced by the Levi-Civita connection, and we show that this space has a non-constant negative scalar curvature. In addition, we consider four submanifolds as special cases, and discuss their geometrical structures, and we prove that one of these submanifolds is an isometric isomorph of the univariate gamma manifold. Then we introduce log-bivariate gamma exponential distributions, which have log-gamma and log-Pareto marginals, and we show that this family of distributions determines a Riemannian 3-manifold which is isometric with the origin manifold. We give an analytical solution for the geodesic equations, and obtain the explicit expressions for Kullback-Leibler distance, J-divergence and Bhattacharyya distance. Finally, we prove that the bivariate gamma exponential manifold can be realized in R4, using information theoretic immersions, and we give explicit information geometric tubular neighbourhoods for some special cases.
Źródło:
World Scientific News; 2020, 143; 181-202
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bivariate Hahn moments for image reconstruction
Autorzy:
Wu, H.
Yan, S.
Powiązania:
https://bibliotekanauki.pl/articles/331058.pdf
Data publikacji:
2014
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
bivariate Hahn moments
bivariate Hahn polynomials
image reconstruction
pattern recognition
odtworzenie obrazu
rozpoznawanie obrazu
Opis:
This paper presents a new set of bivariate discrete orthogonal moments which are based on bivariate Hahn polynomials with non-separable basis. The polynomials are scaled to ensure numerical stability. Their computational aspects are discussed in detail. The principle of parameter selection is established by analyzing several plots of polynomials with different kinds of parameters. Appropriate parameters of binary images and a grayscale image are obtained through experimental results. The performance of the proposed moments in describing images is investigated through several image reconstruction experiments, including noisy and noise-free conditions. Comparisons with existing discrete orthogonal moments are also presented. The experimental results show that the proposed moments outperform slightly separable Hahn moments for higher orders.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2014, 24, 2; 417-428
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characteristics of bivariate binomial distribution
Autorzy:
Wagner, Wiesław
Powiązania:
https://bibliotekanauki.pl/articles/657952.pdf
Data publikacji:
2011
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
bivariate zero-one distribution
bivariate binomial distribution
cumulative distribution function
characterictic function
moments
Opis:
W pracy podano jeden z wielu możliwych sposobów określenia dwuwymiarowego rozkładu dwumianowego. Inne możliwości są wymieniane w pracy Johnsona i in. (1997, s. 31–92). Mają one związek z rozkładem wielomianowym. Podejście proponowane w pracy jest naturalnym rozszerzeniem jednowymiarowego rozkładu zero-jedynkowego i rozkładu dwumianowego. W przypadku dwuwymiarowym proponowana w pracy postać funkcji charakterystycznej w formie rozpisanej i wektorowej pozwoliła na wyprowadzenie wzorów na momenty zwykle i mieszane. Dwuwymiarowy rozkład dwumianowy przy liczbie prób n dążących do nieskończoności przechodzi w dwuwymiarowy rozkład Poissona. a przy pewnych n, p 1 , p 2 przechodzi w graniczny dwuwymiarowy rozkład normalny. Dwuwymiarowy rozkład dwumianowy daje się rozszerzyć na przypadek wielowymiarowy (Johnson i in. 1997. s. 105–113).
Źródło:
Acta Universitatis Lodziensis. Folia Oeconomica; 2011, 255
0208-6018
2353-7663
Pojawia się w:
Acta Universitatis Lodziensis. Folia Oeconomica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
DEVELEOPMENT AND VALIDATION OFSPECTROFLUOROMETRIC AND SPECTROPHOTOMETRIC BIVARIATE METHODS FOR SIMULTANEOUS DETERMINATION OF PROPRANOLOL AND HYDTOCHLOROTHIAZIDE IN DRUG TABLETS
Autorzy:
Wedian, Fadel
AbuAlrob, Rahma
Powiązania:
https://bibliotekanauki.pl/articles/895288.pdf
Data publikacji:
2020-06-29
Wydawca:
Polskie Towarzystwo Farmaceutyczne
Tematy:
propranolol
hydrochlorothiazide
spectrofluorometry
bivariate method
Inderide
Opis:
Spectrofluorometric and spectrophotometric bivariate methods were developed for quantitative of Propranolol and Hydrochlorothiazide in drug tablets in aqueous medium. The methods were tested according to ICH guidelines for linearity, recovery, and specificity and were found accurate, precise, sensitive, and free from interferences. The linearity was established over the ranges 0.025–0.30 and 0.010–0.20 mg/L in the first method, and 1.0–20.0 and 5.0–25.0 mg/L in second method, for PRO and HCT, respectively. The excitation and emission wavelengths were 260, 345 and 270, 415 nm, for PRO and HCT in the first method, respectively. The recoveries were higher than 95% for both methods. Additionally, the results were statistically compared to that of standard chromatographic methods and showed that no significant difference among the methods regarding both accuracy and precision. Thus, the methods were successfully applied to quantitation of PRO and HCT in combined formulations. The proposed methods are reliable, simple, sensitive, and adaptable and could effectively be an alternative method to HPLC.
Źródło:
Acta Poloniae Pharmaceutica - Drug Research; 2020, 77, 3; 453-463
0001-6837
2353-5288
Pojawia się w:
Acta Poloniae Pharmaceutica - Drug Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Tail Dependence in Bivariate Distributions
Zależność w ogonie dla rozkładów dwuwymiarowych
Autorzy:
Jajuga, Krzysztof
Powiązania:
https://bibliotekanauki.pl/articles/905073.pdf
Data publikacji:
2005
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
tail dependence
copula analysis
bivariate distribution
Opis:
W artykule rozpatrywany jest problem zależności w ogonie dla rozkładów dwuwymiarowych. Przedstawiono przegląd różnych podejść do analizowania tej zależności. Szczególna uwaga poświęcona została warunkowym współczynnikom korelacji oraz współczynnikom zależności w ogonie. Wskazano, jak te współczynniki mogą być analizowane za pomocą tzw. analizy połączeń.
In the paper the problem of tail dependence for bivariate data is considerod. The review of different approaches is given. The particular emphasis is put on the conditional correlation coefficients and tail dependence coefficients. It is shown how the latter can be analyzed through copula analysis.
Źródło:
Acta Universitatis Lodziensis. Folia Oeconomica; 2005, 194
0208-6018
2353-7663
Pojawia się w:
Acta Universitatis Lodziensis. Folia Oeconomica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bivariate negative binomial distribution of the Marshall-Olkin type
Autorzy:
Kopocińska, Ilona
Powiązania:
https://bibliotekanauki.pl/articles/1338936.pdf
Data publikacji:
1999
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
bivariate negative geometrical
negative binomial distribution
Opis:
The bivariate negative binomial distribution is introduced using the Marshall-Olkin type bivariate geometrical distribution. It is used to the estimation of the distribution of the number of accidents in standard data.
Źródło:
Applicationes Mathematicae; 1998-1999, 25, 4; 457-461
1233-7234
Pojawia się w:
Applicationes Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
GIS-based technic for roadside-slope stability assessment: an bivariate approach for A1 East-West highway, North Algeria
Autorzy:
Dahoua, L.
Yakovitch, S. V.
Hadji, R. H.
Powiązania:
https://bibliotekanauki.pl/articles/89034.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Wydział Geoinżynierii, Górnictwa i Geologii. Instytut Górnictwa
Tematy:
landslide susceptibility
frequency ratio
bivariate statistics
mountain
geotechnic
Opis:
This paper presents a GIS-based method for landslide susceptibility (LS) assessment using slope-movement inventory and field data. The study has been carried out along A1-Highway (A1-H) in Hanif region as this road section is threated by several types of mass wasting. This hilly zone is known by their landslides sensitive terrains in the North of Algeria. The terrain data are collected from a Géologic map, satellite imageries, digital elevation model, rainfall data, field suveys and ancillary data. In this paper Frequency Ratios (FR) based on bivariate statistical method are evaluated by comparing the observed landslides to their controlling factors. The product of the linear summation of the FR values was a landslide susceptibility index (LSI) map. It was categorized using the natural breaks classification method. The resultant LS zonation map delineates the area into five hierarchic zones. The results confirms that the angle of the slope, plays the most role in wasting especially in road sides. The LS can be used for preliminary land use planning and hazard mitigation purpose. By means of this map the current route of the A1-H can be improved to cross less susceptibles zones.
Źródło:
Mining Science; 2017, 24; 117-127
2300-9586
2353-5423
Pojawia się w:
Mining Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sidon sets and Riesz sets for some measure algebras on the disk
Autorzy:
Gebuhrer, Olivier
Schwartz, Alan
Powiązania:
https://bibliotekanauki.pl/articles/966664.pdf
Data publikacji:
1997
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
disk polynomials
bivariate polynomials
Riesz sets
hypergroups
Sidon sets
Opis:
Sidon sets for the disk polynomial measure algebra (the continuous disk polynomial hypergroup) are described completely in terms of classical Sidon sets for the circle; an analogue of the F. and M. Riesz theorem is also proved.
Źródło:
Colloquium Mathematicum; 1997, 72, 2; 269-279
0010-1354
Pojawia się w:
Colloquium Mathematicum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Estimation of tissue proportions in X-ray CT images using a new mixed pixel distribution
Autorzy:
Glasbey, C. A.
Robinson, C. D.
Powiązania:
https://bibliotekanauki.pl/articles/1954511.pdf
Data publikacji:
1999
Wydawca:
Politechnika Gdańska
Tematy:
bivariate normal distribution
point spread function
sheep breeding
threshold estimation
Opis:
A new probability distribution is obtained, termed the mixed pixel distribution, appropriate for the mixing proportion in digital images when the point spread function has a bivariate normal density. It is used to derive the distribution of pixel values in X-ray CT images where pixels may be a mixture of two tissue types. In a simulation study it is shown that, by fitting this distribution to histograms of pixel values, tissue proportions are estimated more accurately than using threshold-based methods.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 1999, 3, 4; 409-418
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multivariate mapping for experienced users: comparing extrinsic and intrinsic maps with univariate maps
Autorzy:
Korycka-Skorupa, Jolanta
Gołębiowska, Izabela
Powiązania:
https://bibliotekanauki.pl/articles/1955016.pdf
Data publikacji:
2021-12-10
Wydawca:
Uniwersytet Warszawski. Wydział Geografii i Studiów Regionalnych
Tematy:
multivariate map
bivariate map
thematic mapping
user study
eye tracking
Opis:
Multivariate mapping is a technique in which multivariate data are encoded into a single map. A variety of design solutions for multivariate mapping refers to the number of phenomena mapped, the map type, and the visual variables applied. Unlike other authors who have mainly evaluated bivariate maps, in our empirical study we compared three solutions when mapping four variables: two types of multivariate maps (intrinsic and extrinsic) and a simple univariate alternative (serving as a baseline). We analysed usability performance metrics (answer time, answer accuracy, subjective rating of task dificulty) and eye-tracking data. The results suggested that experts used all the tested maps with similar results for answer time and accuracy, even when using four-variable intrinsic maps, which is considered to be a challenging solution. However, eye-tracking data provided more nuances in relation to the diference in cognitive efort evoked by the tested maps across task types.
Źródło:
Miscellanea Geographica. Regional Studies on Development; 2021, 25, 4; 259-271
0867-6046
2084-6118
Pojawia się w:
Miscellanea Geographica. Regional Studies on Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multivariate negative binomial distributions generated by multivariate exponential distributions
Autorzy:
Kopociński, Bolesław
Powiązania:
https://bibliotekanauki.pl/articles/1338938.pdf
Data publikacji:
1999
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
bivariate geometrical distribution
multivariate exponential distribution
multivariate negative binomial distribution
Opis:
We define a multivariate negative binomial distribution (MVNB) as a bivariate Poisson distribution function mixed with a multivariate exponential (MVE) distribution. We focus on the class of MVNB distributions generated by Marshall-Olkin MVE distributions. For simplicity of notation we analyze in detail the class of bivariate (BVNB) distributions. In applications the standard data from [2] and [7] and data concerning parasites of birds from [4] are used.
Źródło:
Applicationes Mathematicae; 1998-1999, 25, 4; 463-472
1233-7234
Pojawia się w:
Applicationes Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Borrowing Information over time in Binomial/Logit Normal Models for Small Area Estimation
Autorzy:
Franco, Carolina
Bell, William R.
Powiązania:
https://bibliotekanauki.pl/articles/465889.pdf
Data publikacji:
2015
Wydawca:
Główny Urząd Statystyczny
Tematy:
area level model
complex surveys
American Community Survey
bivariate
model
SAIPE
Opis:
Linear area level models for small area estimation, such as the Fay-Herriot model, face challenges when applied to discrete survey data. Such data commonly arise as direct survey estimates of the number of persons possessing some characteristic, such as the number of persons in poverty. For such applications, we examine a binomial/logit normal (BLN) model that assumes a binomial distribution for rescaled survey estimates and a normal distribution with a linear regression mean function for logits of the true proportions. Effective sample sizes are defined so variances given the true proportions equal corresponding sampling variances of the direct survey estimates. We extend the BLN model to bivariate and time series (first order autoregressive) versions to permit borrowing information from past survey estimates, then apply these models to data used by the U.S. Census Bureau’s Small Area Income and Poverty Estimates (SAIPE) program to predict county poverty for school-age children. We compare prediction results from the alternative models to see how much the bivariate and time series models reduce prediction error variances from those of the univariate BLN model. Standard conditional variance calculations for corresponding linear Gaussian models that suggest how much variance reduction will be achieved from borrowing information over time with linear models agree generally with the BLN empirical results.
Źródło:
Statistics in Transition new series; 2015, 16, 4; 563-584
1234-7655
Pojawia się w:
Statistics in Transition new series
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the convergence of the Bhattacharyya bounds in the multiparametric case
Autorzy:
Alharbi, Abdulghani
Powiązania:
https://bibliotekanauki.pl/articles/1340569.pdf
Data publikacji:
1994
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
exponential family
characterizations
Seth-Shanbhag results
bivariate distributions
MVUE
Bhattacharyya bounds
diagonal of covariance matrix
Opis:
Shanbhag (1972, 1979) showed that the diagonality of the Bhattacharyya matrix characterizes the set of normal, Poisson, binomial, negative binomial, gamma or Meixner hypergeometric distributions. In this note, using Shanbhag's techniques, we show that if a certain generalized version of the Bhattacharyya matrix is diagonal, then the bivariate distribution is either normal, Poisson, binomial, negative binomial, gamma or Meixner hypergeometric. Bartoszewicz (1980) extended the result of Blight and Rao (1974) to the multiparameter case. He gave an application of this result when independent samples come from the exponential distribution, and also evaluated the generalized Bhattacharyya bounds for the best unbiased estimator of P(Y
Źródło:
Applicationes Mathematicae; 1993-1995, 22, 3; 339-349
1233-7234
Pojawia się w:
Applicationes Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Real-Time Market Abuse Detection with a Stochastic Parameter Model
Autorzy:
Cholewiński, Radosław
Powiązania:
https://bibliotekanauki.pl/articles/483319.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Market abuse detection
insider trading
real-time analysis
timevarying parameters
uni- and bivariate GARCH processes
Opis:
This paper develops a new model of market abuse detection in real time. Market abuse is detected, as Minenna (2003) proposed, on the basis of prediction intervals. The model structure is based on the discrete-time, extended market model introduced by Monteiro, Zaman, Leitterstorf (2007) to analyze the market cleanliness. Parameters of the expected return equation are assumed, however, to be time-varying and estimated under the state-space framework using the extended Kalman filter postulated by Chou, Engle, Kane (1992) to capture the GARCH effect in returns. QML estimation is performed on intraday data; its utilization is proposed as an alternative to the continuous time modeling by Minenna (2003). This framework is generalized to the bivariate case which enables the analysis of daily open/close data. The paper also extends procedures of the statistical verification of the estimated state-space model to include the uncertainty arising from time-invariant parameters.
Źródło:
Central European Journal of Economic Modelling and Econometrics; 2009, 1, 3; 261-284
2080-0886
2080-119X
Pojawia się w:
Central European Journal of Economic Modelling and Econometrics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ultra-short-term wind power prediction based on copula function and bivariate EMD decomposition algorithm
Autorzy:
Liu, Haiqing
Lin, Weijian
Li, Yuancheng
Powiązania:
https://bibliotekanauki.pl/articles/140702.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
bivariate EMD decomposition
copula function
GRU network
meteorological factor
ultra-short-term wind power prediction
Opis:
Against the background of increasing installed capacity of wind power in the power generation system, high-precision ultra-short-term wind power prediction is significant for safe and reliable operation of the power generation system. We present a method for ultra-short-term wind power prediction based on a copula function, bivariate empirical mode decomposition (BEMD) algorithm and gated recurrent unit (GRU) neural network. First we use the copula function to analyze the nonlinear correlation between wind power and external factors to extract the key factors influencing wind power generation. Then the joint data composed of the key factors and wind power are decomposed into a series of stationary subsequence data by a BEMD algorithm which can decompose the bivariate data jointly. Finally, the prediction model based on a GRU network uses the decomposed data as the input to predict the power output in the next four hours. The experimental results show that the proposed method can effectively improve the accuracy of ultra-short-term wind power prediction.
Źródło:
Archives of Electrical Engineering; 2020, 69, 2; 271-286
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł

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