Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "intervals" wg kryterium: Temat

  Lista filtrów
Wyrównaj
Wyświetlanie 1-15 z 29
Tytuł:
A note on confidence intervals for deblurred images
Autorzy:
Biel, Michał
Szkutnik, Zbigniew
Powiązania:
https://bibliotekanauki.pl/articles/255867.pdf
Data publikacji:
2020
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
inverse problems
confidence intervals
convolution
deblurring
Opis:
We consider pointwise asymptotic confidence intervals for images that are blurred and observed in additive white noise. This amounts to solving a stochastic inverse problem with a convolution operator. Under suitably modified assumptions, we fill some apparent gaps in the proofs published in [N. Bissantz, M. Birke, Asymptotic normality and confidence intervals for inverse regression models with convolution-type operators, J. Multivariate Anal. 100 (2009), 2364-2375]. In particular, this leads to modified bootstrap confidence intervals with much better finite-sample behaviour than the original ones, the validity of which is, in our opinion, questionable. Some simulation results that support our claims and illustrate the behaviour of the confidence intervals are also presented.
Źródło:
Opuscula Mathematica; 2020, 40, 3; 361-373
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Identification of Harmonic Musical Intervals : The Effect of Pitch Register and Tone Duration
Autorzy:
Rogala, T.
Miśkiewicz, A.
Rogowski, P.
Powiązania:
https://bibliotekanauki.pl/articles/177073.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
musical intervals
pitch strength
pitch perception
Opis:
An experiment was conducted to explore the effect of the pitch strength of pure tones constituting a dyad on the accuracy of musical interval identification. Pitch strength was controlled by presenting the intervals in different frequency regions and varying their duration. The intervals were organized into 18 blocks made up by a combination of three octaves: the second (65.4-130.8 Hz), the fourth (261.6-523.3 Hz), and the sixth octave (1047-2093 Hz), and six tone durations, ranging 50-2000 ms in the second octave, and 10-500 ms in the two higher ones. The results indicate that interval identification improves with increasing pitch strength of the interval’s component tones. The identification scores were much lower in the second octave than in the two higher ones and in all octaves identification worsened as the interval’s duration was shortened. The intervals were most often confused with intervals of similar size rather than with their inversions and intervals of similar sonic character. This finding suggests that the main cue for the identification of harmonic intervals is the pitch distance between two tones. However, in the low pitch range, when the tone pitches are less salient, the impression of consonance may become a helpful, although not very effective cue.
Źródło:
Archives of Acoustics; 2017, 42, 4; 591-600
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the consistency of sieve bootstrap prediction intervals for stationary time series
Autorzy:
Różański, Roman
Zagdański, Adam
Powiązania:
https://bibliotekanauki.pl/articles/729798.pdf
Data publikacji:
2004
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
prediction intervals
sieve bootstrap
method of sieves
Opis:
In the article, we consider construction of prediction intervals for stationary time series using Bühlmann's [8], [9] sieve bootstrapapproach. Basic theoretical properties concerning consistency are proved. We extend the results obtained earlier by Stine [21], Masarotto and Grigoletto [13] for an autoregressive time series of finite order to the rich class of linear and invertible stationary models. Finite sample performance of the constructed intervals is investigated by computer simulations.
Źródło:
Discussiones Mathematicae Probability and Statistics; 2004, 24, 1; 5-40
1509-9423
Pojawia się w:
Discussiones Mathematicae Probability and Statistics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Confidence bounds for the reliability of a system from subsystem data
Autorzy:
Hryniewicz, O.
Powiązania:
https://bibliotekanauki.pl/articles/2069702.pdf
Data publikacji:
2009
Wydawca:
Uniwersytet Morski w Gdyni. Polskie Towarzystwo Bezpieczeństwa i Niezawodności
Tematy:
reliability
system
confidence intervals
binomial data
exponential data
Opis:
The paper is concerned with the construction of lower bounds for the reliability of a system when statistical data comes from independent tests of its elements. The overview of results known from literature and obtained under the assumption that elements in a system are independent is given. It has been demonstrated using a Monte Carlo experiment that in the case when these elements are dependent and when their dependence is described by Clayton and Gumbel copulas these confidence bounds are not satisfactory. New simple bounds have been proposed which in some practical cases have better properties than the classical ones.
Źródło:
Journal of Polish Safety and Reliability Association; 2009, 1; 157--170
2084-5316
Pojawia się w:
Journal of Polish Safety and Reliability Association
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Event detection in ECG, carotid pulse, phonocardiogram, and detection of consecutive systolic time intervals
Autorzy:
Strasz, A.
Niewiadomski, W.
Skupińska, M.
Gąsiorowska, A.
Laskowska, D.
Leonarcik, R.
Cybulski, G.
Powiązania:
https://bibliotekanauki.pl/articles/384357.pdf
Data publikacji:
2012
Wydawca:
Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów
Tematy:
systolic time intervals
ECG
polyphysiography
automatic signal analysis
Opis:
We developed a program which allows measurement of consecutive time intervals between chosen events in ECG, carotid pulse, and phonocardiogram. Currently it is possible to determine following systolic time intervals (STI): PEP - pre-ejection period, Q-S2 – time between trough of Q wave and aortic valve closure, Q-D - time between trough of Q wave and dicrotic notch, S2-D - time between aortic valve closure and dicrotic notch, as well as QQ interval. Measurements were performed on 30 young, healthy subjects. Subjects were supine, they performed two-minute isometric handgrip (HG) twice. First HG was followed by four-minute rest, second HG by two-minute occlusion of the working arm. Preliminary analyses revealed: 1/ the QQ interval changes were reflected weakly or not at all in changes of STI, 2/ shortening of QQ during handgrip was paralleled by slight decrease of Q-D and Q-S2, 3/ during occlusion, when QQ intervals returned to baseline also Q-D and Q-S2 returned to baseline, despite sustained elevation of arterial pressure, 4/ there were distinct oscillation in the time course of Q-S2 intervals, time course of Q-D intervals was relatively smooth, thus S2 and D may reflect different events contrary to common notation.
Źródło:
Journal of Automation Mobile Robotics and Intelligent Systems; 2012, 6, 3; 13-16
1897-8649
2080-2145
Pojawia się w:
Journal of Automation Mobile Robotics and Intelligent Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Computational intensive methods for prediction and imputation in time series analysis
Autorzy:
Neves, Maria
Cordeiro, Clara
Powiązania:
https://bibliotekanauki.pl/articles/729950.pdf
Data publikacji:
2011
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
bootstrap
forecast intervals
missing data
time series analysis
Opis:
One of the main goals in times series analysis is to forecast future values. Many forecasting methods have been developed and the most successful are based on the concept of exponential smoothing, based on the principle of obtaining forecasts as weighted combinations of past observations. Classical procedures to obtain forecast intervals assume a known distribution for the error process, what is not true in many situations. A bootstrap methodology can be used to compute distribution free forecast intervals. First an adequately chosen model is fitted to the data series. Afterwards, and inspired on sieve bootstrap, an AR(p) is used to filter the series of the random component, under the stationarity hypothesis. The centered residuals are then resampled and the initial series is reconstructed. This methodology will be used to obtain forecasting intervals and for treating missing data, which often appear in a real time series. An automatic procedure was developed in R language and will be applied in simulation studies as well as in real examples.
Źródło:
Discussiones Mathematicae Probability and Statistics; 2011, 31, 1-2; 121-139
1509-9423
Pojawia się w:
Discussiones Mathematicae Probability and Statistics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The use of the bootstrap method for the assessment of investment effectiveness and risk – the case of confidence intervals estimation for the Sharpe ratio and TailVaR
Autorzy:
Jarno, Klaudia
Smaga, Łukasz
Powiązania:
https://bibliotekanauki.pl/articles/2046423.pdf
Data publikacji:
2020-11-09
Wydawca:
Uniwersytet Warszawski. Wydawnictwo Naukowe Wydziału Zarządzania
Tematy:
Bootstrap
confidence intervals
Sharpe ratio
TailVaR
stock market index
Opis:
This paper is aimed at presenting application of bootstrap interval estimation methods to the assessment of financial investment’s effectiveness and risk. At first, we give an overview of various methods of bootstrap confidence interval estimation, i.e. bootstrap-t interval, percentile interval and BCa interval. Then, bootstrap confidence interval estimation methods are used to estimate confidence intervals for the Sharpe ratio and TailVaR of the Warsaw Stock Exchange sectoral indices. The results show that the bootstrap confidence intervals of different types are quite similarly positioned for each of the analysed index and measure. Taking into the account the locations of confidence intervals for both the Sharpe ratio and TailVaR, the real estate sector tends to be the most advantageous from the investor’s viewpoint.
Źródło:
Journal of Banking and Financial Economics; 2020, 1(13); 40-50
2353-6845
Pojawia się w:
Journal of Banking and Financial Economics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A modified PWM three intervals control for a matrix converter in real time
Autorzy:
Rezaoui, M. M.
Nezli, L.
Mahmoudi, M. O.
Kouzou, A.
Abu Rub, H.
Powiązania:
https://bibliotekanauki.pl/articles/964019.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
matrix converter [3×5]
THD
PWM three intervals
real time
Opis:
In this paper, the application of the proposed control strategy PWM three intervals with 3×5 matrix converter is presented and analyzed. This control strategy is developed for the control of the multi-phases matrix converter, where the main aim is to ensure the waveform quality of the output voltages and the input currents based on the THD evaluation. Simulation results and real time implementation on dSpace 1103 of 3×5 matrix converter under R-L load are presented for the validation of the proposed control strategy and to clarify the main related advantages.
Źródło:
Archives of Control Sciences; 2014, 24, 1; 85-98
1230-2384
Pojawia się w:
Archives of Control Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A New Method for Electrocardiogram Features Extraction Using Slope Change Coefficients
Autorzy:
Bensegueni, Skander
Powiązania:
https://bibliotekanauki.pl/articles/2200697.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
ECG waveform peaks
ECG segments and intervals
Slope change coefficients
Opis:
A new method of Electrocardiogram (ECG) features extraction is proposed in this paper. The purpose of this study is to detect the main characteristics of the signal: P, Q, R, S, and T, then localize and extract its intervals and segments. To do so we first detect peaks, onsets and offsets of the signal's waveform by calculating the slope change (SC) coefficients and consequently, the peaks of the signal are determined. The SC coefficients are based on the calculation of the integral of two-scale signals with opposite signs. The simulation results of our algorithm applied on recordings of MIT-BIH arrhythmia electrocardiogram database show that the proposed method delineates the electrocardiogram waveforms and segments with high precision.
Źródło:
International Journal of Electronics and Telecommunications; 2023, 69, 1; 33--39
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Identifying the Climatic Conditions in Iraq by Tracking Down Cooling Events in the North Atlantic Ocean in the Period 3000–0 BC
Autorzy:
Muslih, Khamis D.
Powiązania:
https://bibliotekanauki.pl/articles/2037650.pdf
Data publikacji:
2014-10-10
Wydawca:
Uniwersytet Warszawski. Wydział Geografii i Studiów Regionalnych
Tematy:
Iraq
North Atlantic Oscillation
drift ice indices
drought intervals
Eastern Mediterranean
Opis:
North Atlantic Oscillation (NAO), monthly averages of precipitation in the Baghdad station, and petrologic tracer proxy data for ocean properties in the North Atlantic (NA) have been used in an attempt to identify climatic conditions in Iraq during the study period. The study showed that contemporary changes in precipitation in Iraq are associated with NAO, as a negative relationship is found between them. Moreover, the study found that there is a strong negative correlation between NAOI and SST in NA, where drift ice indices explain between 33–36% of the NAOI variability. The prolonged of cold Holocene periods led to a radical oceanography and atmospheric changes in the NA and the Mediterranean Sea, effectively contributing to the prevalence of cold and drought in the EM, including Iraq. The analysis revealed as many as four intervals of significant cool drought phases prevailing over Iraq during the periods 2650–2500, 2200– 1900,1300–1200 and 1000–850 BC.
Źródło:
Miscellanea Geographica. Regional Studies on Development; 2014, 18, 3; 40-46
0867-6046
2084-6118
Pojawia się w:
Miscellanea Geographica. Regional Studies on Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Minimal trees and monophonic convexity
Autorzy:
Cáceres, Jose
Oellermann, Ortrud
Puertas, M.
Powiązania:
https://bibliotekanauki.pl/articles/743292.pdf
Data publikacji:
2012
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
minimal trees
monophonic intervals of sets
k-monophonic convexity
convex geometries
Opis:
Let V be a finite set and a collection of subsets of V. Then is an alignment of V if and only if is closed under taking intersections and contains both V and the empty set. If is an alignment of V, then the elements of are called convex sets and the pair (V, ) is called an alignment or a convexity. If S ⊆ V, then the convex hull of S is the smallest convex set that contains S. Suppose X ∈ ℳ. Then x ∈ X is an extreme point for X if X∖{x} ∈ ℳ. A convex geometry on a finite set is an aligned space with the additional property that every convex set is the convex hull of its extreme points. Let G = (V,E) be a connected graph and U a set of vertices of G. A subgraph T of G containing U is a minimal U-tree if T is a tree and if every vertex of V(T)∖U is a cut-vertex of the subgraph induced by V(T). The monophonic interval of U is the collection of all vertices of G that belong to some minimal U-tree. Several graph convexities are defined using minimal U-trees and structural characterizations of graph classes for which the corresponding collection of convex sets is a convex geometry are characterized.
Źródło:
Discussiones Mathematicae Graph Theory; 2012, 32, 4; 685-704
2083-5892
Pojawia się w:
Discussiones Mathematicae Graph Theory
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Node assignment problem in Bayesian networks
Autorzy:
Polańska, J.
Borys, D.
Polański, A.
Powiązania:
https://bibliotekanauki.pl/articles/908425.pdf
Data publikacji:
2006
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
biostatystyka
sieci bayesowskie
przedział ufności
biostatistics
Bayesian networks
maximum likelihood
confidence intervals
Opis:
This paper deals with the problem of searching for the best assignments of random variables to nodes in a Bayesian network (BN) with a given topology. Likelihood functions for the studied BNs are formulated, methods for their maximization are described and, finally, the results of a study concerning the reliability of revealing BNs’ roles are reported. The results of BN node assignments can be applied to problems of the analysis of gene expression profiles.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2006, 16, 2; 233-240
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
How reliable is a measure of model reliability? Bootstrap confidence intervals over validation results
Jak wiarygodna jest miara oceny modelu? Bootstrapowe przedziały ufności dla miar dokładności modelu
Autorzy:
Koźniewski, M.
Cypko, M. A.
Drużdżel, M. J.
Powiązania:
https://bibliotekanauki.pl/articles/88378.pdf
Data publikacji:
2016
Wydawca:
Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
Tematy:
sieci bayesowskie
bootstrapowe przedziały ufności
walidacja
Bayesian networks
bootstrap confidence intervals
validation
Opis:
A researcher testing a model will frequently question the reliability of the test results, understanding well the intuition that verification performed on a handful of cases is less reliable than verification based on very large numbers of cases. Because a limited number of verification cases happens pretty often in very specific domains, a question of practical importance is, thus, how reliable is a reported reliability measure. We propose a methodology based on deriving confidence intervals over various measures of accuracy of Bayesian network models by means of bootstrap confidence intervals. We evaluate our approach on ROC and calibration curves derived for a model derived from an UC Irvine Machine Learning Repository data set and a sizeable (over 300 variables) practical model constructed using expert knowledge and evaluated on merely 66 accumulated real patient cases. We show how increasing the number of test cases impacts the width of confidence intervals and how this can aid in estimating a reasonable number of verification cases that will increase the confidence in model reliability.
Przy testowaniu modelu należy zdawać sobie z tego sprawę że weryfikacja modelu przy pomocy małego zbioru danych jest mniej przekonywująca niż weryfikacja bazująca na dużym zbiorze danych. Często napotyka się sytuację, w której do analizy modelu dysponujemy nieznaczną ilością rekordów. Nasuwa się pytanie o wiarygodność oceny modelu. Proponujemy w takiej sytuacji przyjrzeć się bootrstrapowym przedziałom ufności różnych ˙ miar dokładności modelu. W tej pracy określamy bootstrapowe przedziały ufności dla krzywych ROC i krzywych kalibracji modeli uzyskanych z danych z repozytorium UC Irvine. Czynność powtarzamy dla modelu skonstruowanego na podstawie wiedzy ekspertów (ponad 300 zmiennych) i testowanego na 66 zebranych rekordach pacjentów. Pokazujemy jak wzrost liczby rekordów wpływa na szerokość bootstrapowych przedziałów ufności oraz jak taka analiza może pomóc w określeniu liczby rekordów, która może podwyższyć rzetelność weryfikacji modelu.
Źródło:
Advances in Computer Science Research; 2016, 13; 27-41
2300-715X
Pojawia się w:
Advances in Computer Science Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An application of the shortest confidence intervals for fraction in controls provided by Supreme Chamber of Control
Autorzy:
Zieliński, Wojciech
Powiązania:
https://bibliotekanauki.pl/articles/452911.pdf
Data publikacji:
2012
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Katedra Ekonometrii i Statystyki
Tematy:
statistical quality control
alternative rating
experimental design
shortest confidence intervals for fraction
Opis:
In statistical quality control objects are alternatively rated. It is of interest to estimate a fraction of negatively rated objects. One of such applications is a quality control provided by Supreme Chamber of Control (NIK) to find out a percentage of abnormalities in the work among others of tax offices. Mathematical details of experimental designs for alternatively rated phenomena are given in Karliński (2003). Zieliński (2010b) investigated statistical properties of those experimental designs. In the paper, the application of the shortest confidence intervals for fraction in experimental designs is shown. Those intervals were proposed by Zieliński (2010a).
Źródło:
Metody Ilościowe w Badaniach Ekonomicznych; 2012, 13, 2; 134-138
2082-792X
Pojawia się w:
Metody Ilościowe w Badaniach Ekonomicznych
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bayesian and generalized confidence intervals on variance ratio and on the variance component in mixed linear models
Autorzy:
Michalski, Andrzej
Powiązania:
https://bibliotekanauki.pl/articles/729664.pdf
Data publikacji:
2009
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
mixed linear models
variance components
hypothesis testing
confidence intervals
generalized p-values
Opis:
The paper deals with construction of exact confidence intervals for the variance component σ₁² and ratio θ of variance components σ₁² and σ² in mixed linear models for the family of normal distributions $_t(0, σ₁²W + σ²I_t)$. This problem essentially depends on algebraic structure of the covariance matrix W (see Gnot and Michalski, 1994, Michalski and Zmyślony, 1996). In the paper we give two classes of bayesian interval estimators depending on a prior distribution on (σ₁², σ²) for:
1) the variance components ratio θ - built by using test statistics obtained from the decomposition of a quadratic form y'Ay for the Bayes locally best estimator of σ₁², Michalski and Zmyślony (1996),
2) the variance component σ₁² - constructed using Bayes point estimators from BIQUE class (Best Invariant Quadratic Unbiased Estimators, see Gnot and Kleffe, 1983, and Michalski, 2003).
In the paper an idea of construction of confidence intervals using generalized p-values is also presented (Tsui and Weerahandi, 1989, Zhou and Mathew, 1994). Theoretical results for Bayes interval estimators and for some generalized confidence intervals by simulations studies for some experimental layouts are illustrated and compared (cf Arendacká, 2005).
Źródło:
Discussiones Mathematicae Probability and Statistics; 2009, 29, 1; 5-29
1509-9423
Pojawia się w:
Discussiones Mathematicae Probability and Statistics
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 29

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies