Acta Universitatis Lodziensis. Folia Oeconomica: Recent submissions
Now showing items 1461-1480 of 4515
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Methods of Classification Error Decompositions and their Properties
(Wydawnictwo Uniwersytetu Łódzkiego, 2007)The idea of error decomposition originates in regression where squared loss function is applied. More recently, several authors have proposed corresponding decompositions for classification problem, where 0-1 loss is ... -
The Rough Sets Approach to Multicriteria EU ’s Countries Classification Problem Based on Dominance Relation - the Probabilistic Characteristics of Decision Rules
(Wydawnictwo Uniwersytetu Łódzkiego, 2007)The rough sets theory was introduced by Z. Pawlak (1982). The mathematical base on rough sets approach is a binary relation on universe of objects. In the classic rough sets theory there is an indiscemibility relation. ... -
A Proposal for Using Selected Tree-Based Models to Identify Operative Risk Subgroups among Patients Undergoing Coronary Artery Bypass Grafting
(Wydawnictwo Uniwersytetu Łódzkiego, 2007)Classification and regression trees are very popular and attractive types of classifiers, widely used to solve decision-making problems in different fields of science. The study was conducted to identify preoperative ... -
On the Application of Classification Trees to Analyze Customer Loyalty and Satisfaction
(Wydawnictwo Uniwersytetu Łódzkiego, 2007)It became more important to recognize customer expectations and to oiler product properties, which convince customer to buy the analyzed product. In customer loyalty and satisfaction analysis methods, classification trees ... -
Comparative Assessment of Some Selected Methods of Determining the Number of Clusters in a Data Set
(Wydawnictwo Uniwersytetu Łódzkiego, 2007)This paper is an attempt to compare the performance of an algorithm for determining the number of clusters in a data set proposed by the author with other methods of determining the number of clusters. The idea of the ... -
Discrimination of Symbolic Objects
(Wydawnictwo Uniwersytetu Łódzkiego, 2007)Symbolic Data Analysis is an extension of multivariate analysis dealing with data represented in an extended form. Each cell in symbolic data table (symbolic variable) can contain data in form of single quantitative ... -
Feature Selection and Multiple Model Approach in Discriminant Analysis
(Wydawnictwo Uniwersytetu Łódzkiego, 2007)Significant improvement of model stability and prediction accuracy in classification and regression can be obtained by using the multiple model approach. In classification multiple models are built on the basis of training ... -
About Phase Transitions in Kendall’s Shape Space
(Wydawnictwo Uniwersytetu Łódzkiego, 2007)In our article, we discuss the choice of space shape, appropriate for describing an economic process and analyze usefulness of the metrics proposed by I. L. Drуden and K. V. Merida (1998). We introduce and interpret the ... -
Sequential Tests with Power Equal to 1 for Chosen Location Parameters
(Wydawnictwo Uniwersytetu Łódzkiego, 2007)We often verify hypotheses about random variable distribution parameters, when the variable distribution is unknown. In these cases we apply nonparametric tests, in particular nonparametric sequential tests. This paper ... -
Verification of Hypotheses Concerning Parameters of the Regression Model for Complex Samples
(Wydawnictwo Uniwersytetu Łódzkiego, 2007)The paper considers the linear regression function y = βx + ε, where β is a vector of unknown parameters and ε is a rest component. In case of complex samples some modifications of test statistics should be made. Results ... -
Kriging - A Method of Statistical Interpolation of Spatial Data
(Wydawnictwo Uniwersytetu Łódzkiego, 2007)In analyses of spatial phenomena it can sometimes be impossible or very expensive to obtain the value (realization) of a studied phenomenon at all its locations because of practical constraints. Then in order to estimate ... -
Estimation of Bias and Variance of Sample Median by Jacknife and Bootstrap Methods
(Wydawnictwo Uniwersytetu Łódzkiego, 2007)In the paper the estimation of sample median bias and variance by jackknife and bootstrap methods are considered. Monte Carlo analysis of properties of estimators is presented (mean of bias and mean of variance for some ... -
Analysis of Linear Regression Model at Divided System Matrix
(Wydawnictwo Uniwersytetu Łódzkiego, 2007)In this study problems connected with the detection of influential observations are investigated in the linear regression model using the least squares estimation of structural parameters. This issue has been presented ... -
Joint Monitoring of the Mean, Dispersion and Asymmetry in Process Control
(Wydawnictwo Uniwersytetu Łódzkiego, 2007)In this paper the quadratic form of sample mean, sample variance and sample asymmetry is considered. This quadratic form can be used for testing hypothesis on the expected value, variance and asymmetry of observed variable. ... -
Multiple Additive Regression Trees (MART) and their Application
(Wydawnictwo Uniwersytetu Łódzkiego, 2007)Multiple additive regression trees MART is a methodology for trying to solve prediction problems in regression and classification. It’s one of the boosting methods. It was introduced by J. H. Friedman (1999a). Besides ... -
Introduction
(Wydawnictwo Uniwersytetu Łódzkiego, 2007) -
Multiple Endpoints
(Wydawnictwo Uniwersytetu Łódzkiego, 2007)In ANOVA we are mainly based on inter-treatment comparisons. Another common problems arising in biometric studies (especially in biomedical studies) is that of comparing two groups of patients (treatment and a control ... -
On some Inferential Procedures for Receiver Operating Characteristic Curves
(Wydawnictwo Uniwersytetu Łódzkiego, 2006)In the paper two significance tests for receiver operating characteristic curves (ROC) are proposed. Both tests use an asymptotic χ² distribution of the test statistics. -
Some Nonparametric Estimators of Regression Function
(Wydawnictwo Uniwersytetu Łódzkiego, 2007)In the paper some nonparametric estimators of regression function are studied: Nadaraya-Watson estimator and k-nearest neighbour one. Properties of these estimators and possibilities of using them in practice are taken ... -
Wpływ zarządzania ryzykiem finansowym na wartość firmy: analiza teoretycznych przesłanek wpływu zarządzania ryzykiem na wartość firmy
(Wydawnictwo Uniwersytetu Łódzkiego, 2007)The article discusses theoretical premises for the influence of financial risk management on firm’s value. Financial risk management presents a firm with the possibility of a reduction in the volatility of future earnings ...