22 research outputs found
Is it sufficient to assess cost behavior merely by volume of production? Cost behavior research results from Czech Republic
This paper presents results from quantitative research performed as part of a project on cost variability and cost management systems. The main goal was to analyze principal findings that arise through seeking to determine levels of cost management, as well as from comprehending various types of cost behavior affecting manufacturing enterprises in the Czech Republic. The first part summarizes contemporary theories on approaches to cost management that place emphasis on overhead cost management and general and asymmetric cost behavior. The second section deals with the procedure and methodology of the research conducted. Moreover, presentation is given of surveyed questions and hypotheses that form the basis for analysis of particular areas within cost management. The subsequent part presents actual results from research verified through statistically inspecting dependence relations. It was found that the share of overheads was still relatively high, although it had decreased in comparison with figures from previous surveys. Furthermore, there was evidence of significant association between the size of a company and the attention paid to a broadened perception of cost behavior and to monitoring the same. In addition, it was confirmed that senior executives were not aware of issues regarding asymmetric cost behavior or the influence of factors beyond production capacity. It was proven that a dependence exists between the prevalent type of production and complications arising in research, e.g. utilization of the ABC method or monitoring semi-fixed and semi-variable costs. These findings are discussed in the final part of the paper
A depth-based modification of the k-nearest neighbour method
summary:We propose a new nonparametric procedure to solve the problem of classifying objects represented by -dimensional vectors into groups. The newly proposed classifier was inspired by the nearest neighbour (kNN) method. It is based on the idea of a depth-based distributional neighbourhood and is called nearest depth neighbours (kNDN) classifier. The kNDN classifier has several desirable properties: in contrast to the classical kNN, it can utilize global properties of the considered distributions (symmetry). In contrast to the maximal depth classifier and related classifiers, it does not have problems with classification when the considered distributions differ in dispersion or have unequal priors. The kNDN classifier is compared to several depth-based classifiers as well as the classical kNN method in a simulation study. According to the average misclassification rates, it is comparable to the best current depth-based classifiers
Weighted Data Depth and Depth Based Discrimination
The concept of data depth provides a powerful nonparametric tool for multivariate data analysis. We propose a generalization of the well-known halfspace depth called weighted data depth. The weighted data depth is not affine invariant in general, but it has some useful properties as possible nonconvex central areas. We further discuss application of data depth methodology to solve discrimination problem. Several classifiers based on data depth are reviewed and one new classifier is proposed. The new classifier is a modification of k-nearest- neighbour classifier. Classifiers are compared in a short simulation study. Advantage gained from use of the weighted data depth for discrimination purposes is shown
Stochastic modellinf of epidemics
Nazev prace: Stochasticke modelovani epidemii Autor: Oridfej Venealek Katedra: Katedra pravdepodobnosti a matenmticke sta.t.i.stiky Vedouci diplomove prace: Prof. RNDr. .Jaromi'r Antoch. CSe. e-mail vedoucfho: Jaromir.Antoch'3mff.cuni.c-/ Abstrakt: Tato diplomova prace se zabyva modelovanmi prevalence chfipky v Ceske repnb- lice v letech 2001 az 2003. Vychazi z dat laskave ZHpujccnych Statnhn zdravotm'm ustavem. Z hlediska epiclemiologie jde o observaeni deskriptivuf studii: zabyva se rozdelenhn poctu riernocnych chfipko\ v prnbehu sledovaneho ubdobi v ceske populaci. Matematiekym podkla- dem pro modelovaih je nelinearni hierarehicky model. Funkem tvar zavislo.sti prevalence na case vyehazt z teorie rustovyeh kfivek. Klicova slova: prevalence, sledovane obdobi, riistove kfivky, hierarehicky model Title: Stochastic- Modelling of Rpidemy Autor: (Jndrej Vencalek Department: Department of Probability and Mathematical Statistics Supervisor: Prof. RNDr. Jaronn'r Antoch, CSc. Supervisor's e-mail address: Jaromir.Antochl'0.|inff.ei.mi.cz Abstract: This diploma tbesis deals with modelling of prevalence of influenza in the C/ech Republic in the period from 2001 till 2003. It is based on data which were khidly lent by Statin' zdravotni nstav. This work is observational descriptive study from the view of epidemiology:..
Concept of Data Depth and Its Applications
summary:Data depth is an important concept of nonparametric approach to multivariate data analysis. The main aim of the paper is to review possible applications of the data depth, including outlier detection, robust and affine-equivariant estimates of location, rank tests for multivariate scale difference, control charts for multivariate processes, and depth-based classifiers solving discrimination problem
Weighted Data Depth and Depth Based Discrimination
The concept of data depth provides a powerful nonparametric tool for multivariate data analysis. We propose a generalization of the well-known halfspace depth called weighted data depth. The weighted data depth is not affine invariant in general, but it has some useful properties as possible nonconvex central areas. We further discuss application of data depth methodology to solve discrimination problem. Several classifiers based on data depth are reviewed and one new classifier is proposed. The new classifier is a modification of k-nearest- neighbour classifier. Classifiers are compared in a short simulation study. Advantage gained from use of the weighted data depth for discrimination purposes is shown
Stochastic modellinf of epidemics
Nazev prace: Stochasticke modelovani epidemii Autor: Oridfej Venealek Katedra: Katedra pravdepodobnosti a matenmticke sta.t.i.stiky Vedouci diplomove prace: Prof. RNDr. .Jaromi'r Antoch. CSe. e-mail vedoucfho: Jaromir.Antoch'3mff.cuni.c-/ Abstrakt: Tato diplomova prace se zabyva modelovanmi prevalence chfipky v Ceske repnb- lice v letech 2001 az 2003. Vychazi z dat laskave ZHpujccnych Statnhn zdravotm'm ustavem. Z hlediska epiclemiologie jde o observaeni deskriptivuf studii: zabyva se rozdelenhn poctu riernocnych chfipko\ v prnbehu sledovaneho ubdobi v ceske populaci. Matematiekym podkla- dem pro modelovaih je nelinearni hierarehicky model. Funkem tvar zavislo.sti prevalence na case vyehazt z teorie rustovyeh kfivek. Klicova slova: prevalence, sledovane obdobi, riistove kfivky, hierarehicky model Title: Stochastic- Modelling of Rpidemy Autor: (Jndrej Vencalek Department: Department of Probability and Mathematical Statistics Supervisor: Prof. RNDr. Jaronn'r Antoch, CSc. Supervisor's e-mail address: Jaromir.Antochl'0.|inff.ei.mi.cz Abstract: This diploma tbesis deals with modelling of prevalence of influenza in the C/ech Republic in the period from 2001 till 2003. It is based on data which were khidly lent by Statin' zdravotni nstav. This work is observational descriptive study from the view of epidemiology:..
Vážená hloubka dat a diskriminace založená na hloubce dat
The concept of data depth provides a powerful nonparametric tool for multivariate data analysis. We propose a generalization of the well-known halfspace depth called weighted data depth. The weighted data depth is not affine invariant in general, but it has some useful properties as possible nonconvex central areas. We further discuss application of data depth methodology to solve discrimination problem. Several classifiers based on data depth are reviewed and one new classifier is proposed. The new classifier is a modification of k-nearest- neighbour classifier. Classifiers are compared in a short simulation study. Advantage gained from use of the weighted data depth for discrimination purposes is shown.Hloubka dat je jednĂm z neparametrickĂ˝ch nástrojĹŻ pro analĂ˝zu mnohorozmÄ›rnĂ˝ch dat. Práce novÄ› zavádĂ zobecnÄ›nĂ poloprostorovĂ© hloubky, tzv. váženou hloubku dat. Vážená hloubka nenĂ obecnÄ› afinnÄ› invariantnĂ, má však nÄ›kterĂ© dobrĂ© vlastnosti, napĹ™Ăklad Ĺľe jejĂ centrálnĂ oblasti (oblasti s nejvÄ›tšà hloubkou) mohou bĂ˝t nekonvexnĂ. Práce se dále zabĂ˝vá moĹľnostĂ aplikace metodologie hloubky dat v diskriminaÄŤnĂ analĂ˝ze. PĹ™ehled klasifikátorĹŻ zaloĹľenĂ˝ch na hloubce dat je doplnÄ›n o návrh novĂ©ho klasifikátoru, kterĂ˝ je modifikacĂ metody k nejbližšĂch sousedĹŻ. Kvalita klasifikátorĹŻ je vyšetĹ™ována jak teoreticky (asymptotickĂ© vlastnosti), tak i v krátkĂ© simulaÄŤnĂ studii. V závÄ›ru je poukázáno na vĂ˝hody, kterĂ© lze zĂskat pouĹľitĂm novÄ› navrĹľenĂ© váženĂ© hloubky dat.Katedra pravdÄ›podobnosti a matematickĂ© statistikyDepartment of Probability and Mathematical StatisticsFaculty of Mathematics and PhysicsMatematicko-fyzikálnĂ fakult