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Tytuł:
Optymizm a prawidłowości percepcyjne przy ważeniu prawdopodobieństwa
Optimism/Pesimism and the Probability Weighting Function
Autorzy:
Sokołowska, Joanna
Powiązania:
https://bibliotekanauki.pl/articles/468708.pdf
Data publikacji:
2006
Wydawca:
Polska Akademia Nauk. Instytut Filozofii i Socjologii PAN
Tematy:
optimistic predictions
probability weighting function
configural weighting
dispositional optimism
Opis:
The main question of the presented experiments has been whether the probability weighting function (Kahneman, Tversky, 1979) and configural weighting incorporated in the CPT model (Tversky & Kahneman, 1992) can account for the overweighting of positive outcomes and underweigthing of negative outcomes, the phenomena first observed in the 50−ties (Irwin, 1953; Marks, 1951; – Marks-Irwin effect) and called unrealistic optimism in the current literature. In Experiment 1, carried out with 133 students, the relations between expectations of success, weights attributed to positive and 0 outcomes and the objective frequency of such outcomes were investigated in a skill situation, i. e. a competition for the best student paper. It was found that: (1) expectations of success depended strongly on the objective frequency of prizes, (2) the best outcomes were weighted in agreement with predictions of the CPT model, but (3) the same was not true for the worst outcome, i. e. 0. The results, however, could not be easily generalised because the situation was constructed such that no negative outcomes were present and 0 outcome was always the most probable. To extend studies to lotteries with negative outcomes and wider range of probabilities an additional experiment was carried out. In Experiment 2 284 students made choices between 10 pairs of 5-outcome mixed lotteries. These lotteries were constructed such the absolute utilities (calculated from CPT) of positive and negative outcomes were equal, and positive and negative outcomes had the same probabilities of occurrence. According to CPT, such lotteries should be always rejected. because negative outcomes are weighted more heavily, yielding negative overall CPT values of the lotteries. The results, however, did not support such predictions – the acceptance rate was close to 1/ . In general, the binominal distribution of acceptance of gambles with negative CPT values might suggest that some people assign optimistic weights to outcomes, i. e. overweight probabilities of positive outcomes and underweight probabilities of negative outcomes. In particular, individual differences in dispositional optimism (measured with the LOT scale) can reinforce such tendency.
Źródło:
Prakseologia; 2006, 146; 65-88
0079-4872
Pojawia się w:
Prakseologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study and Assessment of Low Frequency Noise in Occupational Settings
Autorzy:
Shehap, A. M.
Shawky, H. A.
El-Basheer, T. M.
Powiązania:
https://bibliotekanauki.pl/articles/177844.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
low frequency noise
A-weighting
C-weighting
audible
method of assessment
Opis:
Low frequency noise is one of the most harmful factors occurring in human working and living environment. Low frequency noise components from 20 to 250 Hz are often the cause of employee complaints. Noise from power stations is an actual problem for large cities, including Cairo. The noise from equipments of station could be a serious problem for station and for environmental area. The development of power stations in Cairo leads to appearing a wide range of gas turbines which are strong source of noise. Two measurement techniques using C-weighted along side the A-weighted scale are explored. C-weighting is far more sensitive to detect low frequency sound. Spectrum analysis in the low frequency range is done in order to identify a significant tonal component. Field studies were supported by a questionnaire to determine whether sociological or other factors might influence the results by using annoyance rating mean value. Subjects included in the study were 153 (mean = 36.86, SD = 8.49) male employees at the three electrical power stations. The (C-A) level difference is an appropriate metric for indicating a potential low frequency noise problem. A-weighting characteristics seem to be able to predict quite accurately annoyance experienced from LFN at workplaces. The aim of the present study is to find simple and reliable method for assessing low frequency noise in occupational environment to prevent its effects on work performance for the workers. The proposed method has to be compared with European methods.
Źródło:
Archives of Acoustics; 2016, 41, 1; 151-160
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On Some Composite Estimator of the Population Mean
O pewnym estymatorze złożonym średniej w populacji
Autorzy:
Gamrot, Wojciech
Powiązania:
https://bibliotekanauki.pl/articles/907039.pdf
Data publikacji:
2008
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
nonresponse
regression
weighting adjustment
Opis:
In this paper an estimator of the finite population mean in the unit nonresponse situation is proposed. It is constructed as a combination of the well-known regression estimator derived from the linear model and a reweighting-type estimator based on a logistic regression model. Combination weights depend on goodness of fit of respective models. Hence, the estimator for which the corresponding model better describes observed sample data dominates in the combination. Some Monte Carlo simulation results revealing its properties are presented.
W artykule zaproponowano estymator złożony średniej w populacji skończonej przy brakach odpowiedzi. Jest on kombinacją estymatora regresyjnego opartego na modelu liniowym i estymatora wykorzystującego ważenie danych opartego na modelu logistycznym. Wagi kombinacji uzależniono od miar dobroci dopasowania tych modeli do danych. Przedstawiono wyniki symulacji wykonanych dla zbadania jego własności.
Źródło:
Acta Universitatis Lodziensis. Folia Oeconomica; 2008, 216
0208-6018
2353-7663
Pojawia się w:
Acta Universitatis Lodziensis. Folia Oeconomica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simultaneous interpretive structural modelling and weighting (SISMW)
Autorzy:
Nasrollahi, Mahdi
Ramezani, Javaneh
Sadraei, Mahmoud
Fathi, Mohammad Reza
Powiązania:
https://bibliotekanauki.pl/articles/2175834.pdf
Data publikacji:
2022
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
SISMW
MCDM
criteria
modelling
weighting
Opis:
Multi-criteria decision-making (MCDM) methods have been implemented in many fields. In the meantime, several methods have been proposed to obtain the weight of the criteria determined by various methods in different ways. In this paper, a new approach, called simultaneous interpretive structural modelling and weighting (SISMW), is proposed to solve a multi-criterion decision-making (MCDM) problem. Using SISMW, the weight of the criteria and the relationship between them could be determined simultaneously. In this approach, like the ISM method, pair comparison between criteria was made by the decision-maker to determine the relationships among the different criteria. With the help of this data, the weight of the criteria, as well as the causal (cause and effect) relationships between them, were determined in 12 steps. The main advantage of this method is that only one stage of data collection is required for obtaining weights and modelling, and so the research process may be faster. This may increase the reliability of the collected data because, in a one-step survey, the impact of time is minimized. This process can be useful for conceptualizing and developing theories to help decisionmakers understand the problem better.
Źródło:
Operations Research and Decisions; 2022, 32, 1; 111--126
2081-8858
2391-6060
Pojawia się w:
Operations Research and Decisions
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Weighting of new starch-polymer salted mud with PT-23 polymer
Autorzy:
Wysocki, S.
Bielewicz, D.
Wysocka, M.
Lewicki, D.
Wilaszek, J.
Powiązania:
https://bibliotekanauki.pl/articles/298703.pdf
Data publikacji:
2014
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
drilling muds
weighting materials
starch mud
Opis:
Rheological properties of mud should assure high rate of penetration and supply maximal hydraulic power to the hole bottom. From this point of view drilling mud should have as little density and viscosity as possible and also minimal solid phase fraction. By the reason of the hole depth and geological conditions in the region it often occurs that maintenance of low density is impossible and drilling mud have to be treated with weighting materials. The process may cause change of mud rheological parameters and cause decrease of penetration rate. In case of weighted mud there is also a problem consisting in sedimentation of weighting material. During these project realization there was developed recipe of new mud for well completion with new PT-23 polymer. The next step was testing of possibilities of weighting the mud with different weighting materials: barite with grain size lower than 75 um, barite with grain size lower than 25 um, commercial barite, hematite, bridging agent M-25. Barite with grain size lower than 75 um and barite with grain size lower than 25 um were conditioned in water, then wet separated into fractions.
Źródło:
AGH Drilling, Oil, Gas; 2014, 31, 1; 157-165
2299-4157
2300-7052
Pojawia się w:
AGH Drilling, Oil, Gas
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
New efficient approximation of weighting functions for simulations of unsteady friction losses in liquid pipe flow
Nowe efektywne funkcje wagowe umożliwiające symulację niestacjonarnych oporów hydraulicznych podczas przepływówniestacjonarnych oporów hydraulicznych podczas przepływów cieczy w przewodach ciśnieniowych
Autorzy:
Urbanowicz, K.
Zarzycki, Z.
Powiązania:
https://bibliotekanauki.pl/articles/280429.pdf
Data publikacji:
2012
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
transient flow
weighting function
friction losses
Opis:
Most papers dealing with calculations and simulations of the unsteady liquid pipe flow are based on the assumption that the formula for quasi-steady friction (Darcy-Weisbach formula) can be applied. In the case of fast changes, like fast transients e.g. water hammer, it fails. In this work, the wall shear stress is presented as a sum of quasi-steady and unsteady component. The unsteady component of the wall shear stress is modeled as a convolution of local fluid acceleration and a weighting function. The original weighting function has usually a very complicated structure, and what is more, makes impossible to carry out an efficient simulation of dynamical runs. In this paper, in order to enable efficient calculation of the unsteady component of the wall shear stress, new weighting functions are presented as sums of exponential components.
W dużej części prac, dotyczących obliczania oraz symulacji niestacjonarnego przepływu cieczy w przewodach ciśnieniowych, opory wyznacza się jedynie z dobrze znanej formuły Darcy-Weisbacha. Niestety w szybkozmiennych przepływach, takich jak np. uderzenie hydrauliczne, założenie quasi-stacjonarności oporów jest poważnym błędem. Wponiższej pracy naprężenie styczne na ściance przewodu wyznacza się z sumy quasi-stacjonarnego składnika oraz niestacjonarnego. Niestacjonarny składnik naprężenia stycznego modelowany jest jako splot lokalnego przyśpieszenia cieczy oraz funkcji wagi. Klasyczne funkcje wagi mają skomplikowaną postać, co uniemożliwia efektywne wyznaczanie oporów. W tej pracy przedstawione zostały nowe efektywne postacie funkcji wagowych o rozszerzonych zakresach stosowalności.
Źródło:
Journal of Theoretical and Applied Mechanics; 2012, 50, 2; 487-508
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An hourly reference evapotranspiration model as a tool for estimating plant water requirements
Autorzy:
Treder, W.
Klamkowski, K.
Powiązania:
https://bibliotekanauki.pl/articles/100923.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Stowarzyszenie Infrastruktura i Ekologia Terenów Wiejskich PAN
Tematy:
weighting lysimeter
Penman-Monteith model
irrigation
Opis:
The usefulness of estimating hourly reference evapotranspiration for assessing the water requirements of plants over a 24-hour period was determined in the study. The values of hourly (ET0,h) and daily (ET0,d) evapotranspiration were calculated using the Penman-Monteith (PM) model. The daily ET0 was calculated automatically by the meteorological station, and the evapotranspiration values for individual hours were calculated using spreadsheet software. To verify the values of evapotranspiration calculated with these two approaches in relation to the actual water needs of grass, lysimetric measurements were performed. Additionally, substrate moisture content and temperature were measured using capacitance probes. The values of evapotranspiration estimated with the hourly PM model were higher than those determined with the daily model. An accuracy of the hourly model in relation to the data measured with a weighing lysimeter depended largely on the quality of the reproduction of meteorological parameters at the site of the crop. Observed underestimation of the actual daily evapotranspiration was presumably due to the use of air temperature values in the calculations (measured at a height of 2 m by the weather station). During strong solar radiation the air temperature was much lower than the temperature of the upper layer of the substrate in the weighing lysimeter. Reference evapotranspiration was recalculated by introducing into the hourly PM model the measured values of substrate temperature. After taking into consideration the higher temperatures, the calculated values of evapotranspiration increased, and the regression model took the form: y = 1.01x + 0.014 (R2 = 0.90), which proves the proportionality of the calculated and measured (actual water needs determined with the weighing lysimeter) data. Reliable data on the hourly variations in evapotranspiration over a 24-hour period can be a great tool for use in controlling the irrigation of plants grown in a limited volume of substrate.
Źródło:
Infrastruktura i Ekologia Terenów Wiejskich; 2017, II/1; 469-481
1732-5587
Pojawia się w:
Infrastruktura i Ekologia Terenów Wiejskich
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A note on face coloring entire weightings of plane graphs
Autorzy:
Jendrol, Stanislav
Šugerek, Peter
Powiązania:
https://bibliotekanauki.pl/articles/31232002.pdf
Data publikacji:
2014-05-01
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
entire weighting
plane graph
face colouring
Opis:
Given a weighting of all elements of a 2-connected plane graph $G = (V,E, F)$, let $f(α)$ denote the sum of the weights of the edges and vertices incident with the face α and also the weight of α. Such an entire weighting is a proper face colouring provided that $f(α) ≠ f(β)$ for every two faces α and β sharing an edge. We show that for every 2-connected plane graph there is a proper face-colouring entire weighting with weights 1 through 4. For some families we improved 4 to 3.
Źródło:
Discussiones Mathematicae Graph Theory; 2014, 34, 2; 421-426
2083-5892
Pojawia się w:
Discussiones Mathematicae Graph Theory
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Consistent Estimation of Cross-Classified Domains
Autorzy:
Lumiste, Kaur
Powiązania:
https://bibliotekanauki.pl/articles/466094.pdf
Data publikacji:
2011
Wydawca:
Główny Urząd Statystyczny
Tematy:
Consistent estimation
calibration
AC-calibration
repeated weighting
Opis:
Domain estimation has become an important area in survey sampling, however a lot of problems associate with it. One out of many is the lack of consistency between different surveys. The results of one survey do not coincide with the results of another survey done earlier or simultaneously, although the same variable is under study. We study two methods, AC-calibration (A – auxiliary, C – common) and repeated weighting (RW), for achieving consistency. A short overview of these two methods is given, and we develop formulas for a specified case, for the crossclassified domains. We assume that there are two sources of information on the study variables (either surveys or registers). The problem is that one source has information on domains formed by certain categorical variable, not considered or not identified in the other source. Instead, this second source has information on domains formed by another categorical variable. We are however interested in domains cross-classified with these categorical variables. A survey is done regarding these new domains, but the domain estimates will probably be inconsistent with marginal information, from earlier surveys. We require that the new domain estimates be consistent with the marginals. To achieve this we apply AC-calibration or repeated weighting. The formulas of AC-calibration and RW for the cross-classified domains are tested in a simulation study. Simulations were done on a population composed of real data from the Estonian Household Survey.
Źródło:
Statistics in Transition new series; 2011, 12, 2; 253-264
1234-7655
Pojawia się w:
Statistics in Transition new series
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Non-response and Weighting Systems in Business Tendency Surveys: Are Expectations Influenced?
Autorzy:
Tomczyk, Emilia
Kowalczyk, Barbara
Powiązania:
https://bibliotekanauki.pl/articles/500709.pdf
Data publikacji:
2011
Wydawca:
Szkoła Główna Handlowa w Warszawie
Tematy:
expectations
rationality
non-response
weighting
survey data
Opis:
Rationality of economic agents belongs to the basic assumptions of neoclassical economic theory, and for decades it has inspired research on whether expectations are indeed formed rationally. Direct data on expectations are available mainly through business tendency surveys which are subject to various types of non-response problems. Inclination of industrial enterprises to respond may be correlated with values of measured variable, introducing response bias. Response bias may also occur as a result of introducing weighting systems to control variable size of respondents. The two key properties of rational expectations, on which the majority of empirical analyses of survey data are focused, are unbiasedness and orthogonality. We analyze several sample balance statistics and expectations series based on quantified survey data, taking into consideration issues of non-response and weighting schemes. Alternative definitions of expectations series aim to account for: 1) influence of arbitrary assumptions concerning weighting of individual data, 2) changing sample structure that results from non-response, 3) response rates varying with degree of optimism / pessimism of respondents. Results of our analysis indicate that expectations concerning relative changes in production are unbiased but not efficient with respect to freely available information, namely, observed relative changes in production (lagged three months) and expectations balance (lagged two months). This result holds for a range of weighting schemes and non-response issues analyzed, including changes introduced to sample structure by non-response, and increased inclination of “optimists” and “pessimists” to supply answers in the business tendency survey, as long as their shares remain constant in time.
Źródło:
Prace i Materiały Instytutu Rozwoju Gospodarczego SGH; 2011, 86:Business Surveys, Business Cycles. Polish Contribution to the 30th CIRET Conference; 101-119
0866-9503
Pojawia się w:
Prace i Materiały Instytutu Rozwoju Gospodarczego SGH
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Estimating the substrate water status using capacitance measurements
Autorzy:
Klamkowski, K.
Treder, W.
Powiązania:
https://bibliotekanauki.pl/articles/101065.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Stowarzyszenie Infrastruktura i Ekologia Terenów Wiejskich PAN
Tematy:
moisture sensor
irrigation
ornamental nursery
weighting lysimeter
Opis:
The suitability of capacitance probes for measuring the actual variations in substrate water content in container-grown ornamental species (Lawson cypress) was examined. The probes were installed in the plant containers. Weighing measurement data on water loss was used to assess the actual changes in substrate water content (plant water use). In an additional test, an evaluation of temperature sensitivity of the capacitance probe was performed under laboratory conditions. The probe was placed in a container containing the growing medium (peat substrate) with a defined (stable) moisture content. The substrate temperature was modified and the changes in probe output were recorded. The experiment demonstrated the existence of the effect of temperature on the quality of soil moisture measurements conducted with the capacitance method. The accuracy of the results obtained from measurements with dielectric sensors in relation to the data obtained by means of weighing platforms depended largely on the temperature profile of the measured medium. It was demonstrated that temperature variations explained 99% of the observed differences in the results of moisture content measured with the capacitance method. Due to the fact that there is no possibility of developing universal factors (for different sensors and substrates) for correcting the influence of temperature, this relationship should be defined independently for a given type of crop and the measuring system available.
Źródło:
Infrastruktura i Ekologia Terenów Wiejskich; 2017, II/1; 521-533
1732-5587
Pojawia się w:
Infrastruktura i Ekologia Terenów Wiejskich
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Improved method for simulating frictional losses in laminar transient liquid pipe flow
Autorzy:
Urbanowicz, K.
Zarzycki, Z.
Kudźma, S.
Powiązania:
https://bibliotekanauki.pl/articles/1943217.pdf
Data publikacji:
2010
Wydawca:
Politechnika Gdańska
Tematy:
unsteady pipe flow
unsteady friction
weighting function
Opis:
This paper is devoted to the problem of energy dissipation and it concerns unsteady friction modeling of the liquid flow in hydraulic lines. One dimensional (1D) quasi-steady model of energy dissipation is in common use. It means that the loss of energy is estimated by the Darcy-Weisbach formulae. Such an approximation is close to reality only for slow changes of the velocity field in the pipe cross-section. In case of fast changes, like fast transients, e.g. water hammer, it fails. In this work the wall shear stress (defined as an effect of unsteady fluid friction) is presented as a sum of quasi-steady and unsteady components. The unsteady component of the wall shear stress is modeled as an convolution of the local fluid acceleration and a weighting function w(t). The weighting function, in general, makes an allowance for a relation of the historic velocity changes and the unsteady component of the wall shear stress. Primitive weighting functions have usually very complicated structures, and what is more, they make it impossible to perform an efficient simulation of dynamical runs. In this paper, a new weighting function is presented as a sum of exponential components in order to enable efficient calculation of the unsteady component wall shear stress. A few examples of the new effective method of unsteady wall shear stress simulations, in case of the water hammer, are presented. The results of the calculations are compared with experiments known in literature and satisfying results are obtained.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2010, 14, 3; 175-188
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
APPLICABILITY OF THE EVIDEM MULTI-CRITERIA DECISION ANALYSIS FRAMEWORK FOR ORPHAN DRUGS – RESULTS FROM A STUDY IN 7 EURASIAN COUNTRIES.
Autorzy:
Baran-Kooiker, Aleksandra
ATIKELER, Kagan
GAITOVA, KAMILLA
HOLOWNIA-VOLOSKOVA, MALWINA
TURCU-STIOLICA, ADINA
Kooiker, Coen
PINIAZHKO, ORESTA
CZECH, MARCIN
Powiązania:
https://bibliotekanauki.pl/articles/895230.pdf
Data publikacji:
2019-06-28
Wydawca:
Polskie Towarzystwo Farmaceutyczne
Tematy:
rare diseases
MCDA
orphan drugs
EVIDEM
HTA
weighting
Opis:
Several Multi-Criteria Decision Analysis (MCDA) models for use in health technology assessment (HTA) have been developed over the years, including some for orphan drugs (OD). However, there is no general consensus yet on MCDA structure and which criteria should be included and implementation of MCDA into HTA practice has been slow so far. Our study tested the criteria preferences and possibilities for implementation of the EVIDEM MCDA framework for OD with a diverse group of 140 stakeholders in Kazakhstan, Netherlands, Poland, Romania, Russia, Turkey and Ukraine (KZ,NL,PL,RO,RU,TR,UA). The research elicited stakeholder preferences (weighting) for EVIDEM domains, criteria and sub-criteria to measure their relative importance. Correlations of work place and HTA/rare diseases experience with weighting results were investigated. Results showed that the ‘Need for intervention’ domain was assessed as the most important in: RO/NL/RU/TR, in KZ/PL the ‘Type of benefit of intervention’ and in UA ‘Economic consequences of intervention’. ‘Population Priorities’ was uniformly given a low priority. Further research, sharing of experiences and multi-stakeholder discussion is necessary to define a path forward for a robust and sustainable improvement of MCDA models and its application in orphan drug HTA. Model simplification and clarification of outcomes would be beneficial.
Źródło:
Acta Poloniae Pharmaceutica - Drug Research; 2019, 76, 3; 581-598
0001-6837
2353-5288
Pojawia się w:
Acta Poloniae Pharmaceutica - Drug Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Joint Calibration Estimator for dual frame surveys
Autorzy:
Elkasabi, Mahmoud A.
Heeringa, Steven G.
Lepkowski, James M.
Powiązania:
https://bibliotekanauki.pl/articles/465638.pdf
Data publikacji:
2015
Wydawca:
Główny Urząd Statystyczny
Tematy:
dual-frame estimation
calibration weighting
auxiliary variables
domain misclassification
Opis:
Many dual frame estimators have been proposed in the statistics literature. Some of these estimators are theoretically optimal but hard to apply in practice, whereas others are applicable but have larger variances than the first group. In this paper, a Joint Calibration Estimator (JCE) is proposed that is simple to apply in practice and meets many desirable properties for dual frame estimators. The JCE is asymptotically design unbiased conditional on the strong relationship between the estimation variable and the auxiliary variables employed in the calibration. The JCE achieves better performance when the auxiliary variables can fully explain the variability in the study variables or at least when the auxiliary variables are strong correlates of the estimation variables. As opposed to the standard dual frame estimators, the JCE does not require domain membership information. Even if included in the JCE auxiliary variables, the effect of the randomly misclassified domains does not exceed the random measurement error effect. Therefore, the JCE tends to be robust for the misclassified domains if included in the auxiliary variables. Meanwhile, the misclassified domains can significantly affect the unbiasedness of the standard dual frame estimators as proved theoretically and empirically in this paper.
Źródło:
Statistics in Transition new series; 2015, 16, 1; 7-36
1234-7655
Pojawia się w:
Statistics in Transition new series
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Weighting function approximation in transient pipe flow
Autorzy:
Urbanowicz, K.
Powiązania:
https://bibliotekanauki.pl/articles/1933953.pdf
Data publikacji:
2012
Wydawca:
Politechnika Gdańska
Tematy:
numerical fluid mechanics
transient flow
hydraulic resistance
weighting function
Opis:
A very important problem in the transient liquid pipe flow analysis is accurate and effective modeling of hydraulic resistance. The so called integral convolution of the mean local acceleration of liquid and a weighting function need to be solved in a numerical way in order to simulate unsteady resistance. A necessary condition in effective numerical calculations is that the weighting function needs to be defined as a finite sum of exponential terms. The function keeps a constant shape in a laminar flow, in a turbulent flow, its shape changes and it is dependent on the instantaneous Reynolds number. In this article an easy method is presented to determine a proper weighting function in a very straightforward manner in a quick time. A comparison of the determined functions and function prototypes in a frequency domain will be presented as well.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2012, 16, 3-4; 263-276
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł

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