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Contingency table analysis from questionnaire survey data of drivers
Velacková, Barbora ; Šulc, Zdeněk (advisor) ; Pecáková, Iva (referee)
The bachelor thesis deals with the contingency table analysis from questionnaire survey data of drivers. The data were obtained from the agency Data Collect s.r.o., which conducted the survey in 2014. The aim of the thesis is to analyse the behaviour of drivers and their habits, which could increase the risk of accidents. The thesis is divided into two main parts; in the first one, methods of contingency table analysis are described; in the second one, the presented analyses are applied to the survey data. Firstly, the behaviour of single and young drivers is analysed, then the differences between men and women drivers. Calculations were made using the software SPSS and MS Excel, in which all the graphs and tables were made.
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Assessment of education quality as factor of employability on a job market of University od Economics in Prague graduates
Bezděk, Jaroslav ; Fischer, Jakub (advisor) ; Pecáková, Iva (referee)
This bachelor thesis focuses on research of university education assessment from the University of Economics in Prague, with accent on Faculty of Informatics and Statistics. However, the main aim of the bachelor thesis is to analyse, if any item of university education evaluation can be considered to become an employability factor for graduates on a job market, even five years after their graduation. Analysis was made over the data file from REFLEX 2013 survey via questionnaire. Quality of university education was researched with the aid of frequency tables and employability factors were researched on calculation of dependence rates for nominal and ordinal variables. Benefit of the bachelor thesis is firstly in option to use results for making a level of education at the University of Economics in Prague better. For example, there was found out, that nowadays students at Faculty of Informatics and Statistics do not have so good communication skills in foreign language to be acceptable in their present job.
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Selection Bias Reduction in Credit Scoring Models
Ditrich, Josef ; Hebák, Petr (advisor) ; Pecáková, Iva (referee) ; Zamrazilová, Eva (referee)
Nowadays, the use of credit scoring models in the financial sector is a common practice. Credit scoring plays an important role in profitability and transparency of lending business. Given the high credit volumes, even a small improvement of discriminatory and predictive power of a credit scoring model may provide a substantial additional profit. Scoring models are applied on the through-the-door population, however, for creating them or adjusting already existing credit rules, it is usual to use only the data corresponding to accepted applicants for which payment discipline can be observed. This discrepancy can lead to reject bias (or selection bias in general). Methods trying to eliminate or reduce this phenomenon are known by the term reject inference. In general, these methods try to assess the behavior of rejected applicants or to obtain an additional information about them. In the dissertation thesis, I dealt with the enlargement method which is based on a random acceptance of applicants that would have been rejected. This method is not only time consuming but also expensive. Therefore I looked for the ways how to reduce the cost of acquiring additional information about rejected applicants. As a result, I have proposed a modification which I called the enlargement method with sorting variable. It was validated on real bank database with two possible sorting variables and the results were compared with the original version of the method. It was shown that both tested approaches can reduce its cost while retaining the accuracy of the scoring models.
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The analysis of dependence of the material deprivation of the households in the Czech Republic on the selected indicators
Cafourková, Magdalena ; Řezanková, Hana (advisor) ; Pecáková, Iva (referee)
The aim of this thesis is to analyse the material deprivation of the households with regard to the selected indicators, i.e. the costs that the household spends on housing, a region where the household is located, the number of the members and the dependent children in the household, age and sex of a head of the household, and economic activity and education level of the members of the household. The thesis aims not only to prove the dependence among the selected indicators but also to quantify this dependence by using the odds ratio. The individual effect of all variables was proven except of the one related to the number of the dependent children. It was also demonstrated that the factors constituting a threat for the households by a material deprivation rate vary by the different age groups. However, it can be concluded that across all the age groups, the material deprivation rate is determined by the sex of a head of the household, education level of the members of the household, and the costs that the household spends on housing.
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Methods of analysing multivariate contingency tables
Šulc, Zdeněk ; Pecáková, Iva (advisor) ; Coufalová, Petra (referee)
This thesis occupies with a relationship of two significant methods of analyzing multivariate contingency tables, namely correspondence analysis and loglinear models. The thesis is divided into three parts. The first one is dedicated to basic terms of categorical data analysis, mainly to contingency tables and their distributions. Primarily, the emphasis is placed on their multidimensional form. The second part presents tools and techniques of both methods in a scope needed for their practical use and interpretation of their results. A practical application of both methods is included in the third part which is presented on the data from a market research. This part describes settings for both analyses in a statistical software SPSS and the subsequent interpretation of their outputs. A comparison of analyzed methods in terms of their use can be found in the conclusion.
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Statistical Analysis of Temperature and Precipitation Time Series in the Czech Republic in Period 1961-2008
Helman, Karel ; Pecáková, Iva (advisor) ; Čermák, Václav (referee) ; Žák, Michal (referee)
The present dissertation deals with an analysis of monthly time series of average temperatures and precipitation sums recorded at 44 sites in the Czech Republic over the period of 1961--2008. The main research purpose is to acquire deeper knowledge of regularities in the climatic time series development, using an appropriate set of statistical methods. A secondary objective is to search and find correlations between the research outcomes and basic geographic coordinates (altitude, longitude and latitude) of particular measurement stations and comparing all the results achieved for the selected climatic elements. There are two major contributions of this work. In the first place, it presents new knowledge in the field of climatic time series, particularly in connection with the strength and development of their seasonal component, further for instance analysing the relation between the distribution of a residual component and the geographic coordinates of the measurement stations. Another contribution lies in an extensive application of statistical methods of climatic time series analysis. Several types of methods were used, having employed both widely and rarely applied statistical tools (linear trends analysis and Box-Jenkins methodology respectively) as well as those used for the very first time (moving-seasonal time series).
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Visualization of Multivariate Statistical Data
Maroušek, Vít ; Pecáková, Iva (advisor) ; Černý, Jindřich (referee)
The thesis deals with the possibilities of visualization of multivariate statistical data. Since this is a very broad area the thesis is divided into four sections, two of which are theoretically and two practically oriented. The first section is devoted to theoretical aspects of data visualization. It contains information about the building blocks of graphs, and how the brain processes graphs in various stages of perception. The second section charts the available chart types that can be used to display data. Selected types of graphs for continuous and discontinuous multidimensional data are described in detail. The third section focuses on available software tools for creating graphs. The section describes several programs, with focus on STATISTICA, R and MS Excel. The knowledge gained in previous chapters was sufficient source of information to perform a graphical analysis of multidimensional continuous and discrete data and using advanced analytical methods in the last section. This analysis is performed separately on the data file with continuous variables and on a data file with discontinuous (categorical) variables.
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The data analysis on perception of quality of life in European cities
Pulcová, Petra ; Jarošová, Eva (advisor) ; Pecáková, Iva (referee)
This bachelor's thesis is about data analysis on perception of quality of life in European cities based on survey, which was made in 2009 by European commission. Theoretical part is focused on explaining the concept of quality of life and basic methods of correlation analysis. At the end is dissertating about some methods for determining order of units by more than one benchmark. Practical part it is focused on correlation analysis, calculation of correlation coefficients and determining order of cities.
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Statistical inference for categorical data analysis
Kocáb, Jan ; Pecáková, Iva (advisor) ; Coufalová, Petra (referee)
This thesis introduces statistical methods for categorical data. These methods are especially used in social sciences such as sociology, psychology and political science, but their importance has increased also in medical and technical sciences. In the first part there is mentioned statistical inference for a proportion. Here is written about classical, exact and Bayesian methods for estimating and hypothesis testing. If we have a large sample then we can approximate exact distribution by normal distribution but if we have a small sample cannot use this approximation and it is necessary to use discrete distribution which makes inference more complicated. The second part deals with two categorical variables analysis in contingency tables. Here are explained measures of association for 2 x 2 contingency tables such as difference of proportion and odds ratio and also presented how we can test independence in the case of large sample and small one. If we have small sample we are not allowed to use classical chi-squared tests and it is necessary to use alternative methods. This part contains variety of exact tests of independence and Bayesian approach for the 2 x 2 table too. In the end of this part there is written about a table for two dependent samples and we are interested whether two variables give identical results which occurs when marginal proportions are equal. In the last part there are methods used on data and discussed results.
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Possibilities of the graphical analysis of categorical data
Rytíř, Michal ; Pecáková, Iva (advisor) ; Löster, Tomáš (referee)
The goal of my work was described the possibilities of the graphical analysis of categorical data. The first part is about clarifying the concept of categorical data and the rules of charting; the second part about the column and the pie chart, which are used most frequently. The last part presents graphical displays which often have variety properties and they are not used in normal commercial statistical programs. For example they allow a visual test of the hypothesis of independence. These are fourfold displays, sieve diagram, trilinear plot and mosaic display.
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