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The temporospatial dimension of health in ZimbabweChazireni, Evans 03 1900 (has links)
Inequalities in levels of health between regions within a country are frequently regarded
as a problem. Zimbabwe is characterised by poor and unequal conditions of health (both the state of
people’s health and health services). The health system of the country shows severe spatial
inequalities that are manifested at provincial, district and even local levels. This research
therefore examines and analyses the spatial inequalities and temporal variation of health
conditions in Zimbabwe. Composite indices were used to determine the people’s state of health in
Zimbabwe. Administrative districts were ranked according to the level of people’s state of health.
Cluster analysis was also performed to demarcate administrative districts according the level
of health service provision. Districts with minimum difference were demarcated in a single
cluster. Clusters were delineated using data on patterns of diseases and health and such clusters
were used to demarcate the country’s spatial health system according to the Adapted
Epidemiological Transition Model. This was used to evaluate the applicability of the model to
Zimbabwe. It emerged from the research that generally the country’s health conditions are poor and
the health system is characterised by severe spatial inequalities. Some districts are experiencing
poor health service provision and serious health challenges and are still in the age of pestilence
and famine but others have good health service provision as well as highly developed health
conditions and are in the age degenerative diseases of the epidemiological transition model. It
further emerged that the country’s health has been evolving with signs of improvement since the
1990s. Recommendations were made regarding possible adjustment to previous strategies and policies
used in Zimbabwe, for the development of the health system of the country. New strategies were also
recommended for the improvement of the health system of the country. Some proposals
are made for further research on the spatial development of health in the country. / Geography / D. Litt et. Phil. (Geography)
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The identification of criteria for the optimal use of Facebook pages for marketing purposes in South Africa : an exploratory studyBarnard, Sune Mari 04 1900 (has links)
The development of non-traditional communication channels in recent years has progressively created a world more digital, networked and interlaced by a myriad of communication tools than ever before. With Facebook being the most prevalent social network, this study aims to guide local organisations to use Facebook optimally to communicate with their customers. The study strives to incorporate the latest ideas about social media marketing in the relevant literature with the opinions of local social media marketing experts. The generally ineffective use of Facebook as a communication channel by small, inexperienced organisations is seen as a justification for identifying a set of criteria to guide organisations in using Facebook pages as a driver of communication. The empirical phase of the research produced a list of seven guidelines on the optimal use of Facebook pages for marketing purposes, which might assist South African companies in developing their marketing strategies. / Business Management / M. Com. (Business Management)
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吸菸者市場區隔化與產品定位之研究鄒義強, ZOU, YI-GIANG Unknown Date (has links)
一、研究目的:自從菸酒開放自由進口後,國內市場競爭更加劇烈,而反菸團體的活
動,消費者對健康意識的警悟,以及潛在消費人口結構的改變,都造成業者在經營上
的挑戰,本研究目的在試擬業者行銷策略。
二、文獻:本研究應用消費行為理論,生活型態理論,市場區隔理論,產品定位理論
及相關文獻。
三、研究方式:本研究採用問卷方式來收集初級資料,採用因素分析法,集群分析法
,多元尺度法,區別分析法,卡方檢定與變異數分析法。
四、研究內容:根據問卷資料萃取生活型態構面,並進行市場區隔,並對不同特徵消
費群在人口統計變項,評估準則,消費行為上加以剖析其差異性。並針對吸菸者對品
牌與屬性的知覺與偏好態度作產品定位分析,以了解競爭態勢,與品牌理想點分析。
五、研究結果:本研究共區隔四個消費群簇,此四群在人口統計變項,消費行為,生
活型態構面與評估準則上均有顯著性的差異。第群訴求重點在於低價格。第二群訴求
重點在於翩翩紳士風度,第群訴求重點在於男子氣概,反抗權威的形象,第四群訴求
重點在於低尼古丁,低焦油含量。
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我國微電腦產業國際行銷策略與績效關係之研究劉安國, LIU, AN-GUO Unknown Date (has links)
研究目的:探討微電腦廠商在不同國際市場行銷策略的差異、最適之行銷組合及其對
績效的影響。
文獻探討:1.學者們對國際行銷策略應採行標準化(Levitt 1983)或因地制
宜(Sorenson and Weichmann1975,Buzzell 1980)迭有爭議。
2.陳正男(1985)曾利用集群分析將行銷策略分成擴張策略、中庸策略及防禦
策略,發現採行擴張策略的廠商其成長率皆高於採行防禦策略的廠商。
研究方法:1.資料收集:初級資料以郵寄問卷獲得,次級資料則蒐集期刊、資策會
研究報告及相關報章雜誌而得。
2.抽樣方法:以我國微電腦外銷前三十名廠商及參加1987年台北國際電腦展之
微電腦公司為樣本。
3.資料分析:以集群分析獲得行銷策略型態之分類,再利用ANOVA探討行銷策
略型態與績效之關係。
研究內容:實際調查各廠商在美加、西歐、東南亞、澳紐四個地區其產品策略、通路
策略、訂價策略、及惟廣策略的做法。
研究結果:我國微電腦產業依不同地區的市場特性,有不同的行銷策略,亦獲得不同
的行銷績效。
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數學規劃在叢聚分析上的應用研究江振東, JIANG, ZHEN-DONG Unknown Date (has links)
通常,在我們所取得的任意一組資料裡,由於內在特性的關係,往往會使資料自然形
成若干叢聚(Clusters)。叢聚分析(Cluster Analysis)的目的,就是如何藉由數
量的方法,找出這些自然形成的叢聚,俾便於往後資料的整理和分析。儘管界定叢聚
的角度,將因人、因事而有所不同。然而根本上,這就是一個尋找最佳解的方法,來
找出資料中的最理想分組,便成為一種自然而可行的嘗試。本文係就動態規劃、整數
規劃(整數規劃模式改以Subgradient Method求解)、暨分支定限法(Brandhand-bo
und Method)如何處理叢聚分析問題,分別予以討論比較。
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用戶別售電量與電費收入之研究:台電公司實證案例 / A Study on Customer-by-Category Energy Sales and Power Sales Revenue Model: The Case of Taiwan Power Company蔡佩容 Unknown Date (has links)
本文旨在檢定台電公司現行季節電價月份劃分之合理性,並探討影響用戶別售電量與電費收入之經濟因素。為達成此目的,本文先就負載觀點與成本觀點進行群集分析,以檢定季節電價是否具統計意義之正當性;其次建立經濟計量模型,分別採用戶別之總售電量與總電費收入做為被解釋變數,運用民國88年1月至民國91年12月之月資料進行實證分析。本文建立之經濟模型有二,分別為時間序列以及複迴歸方程式模型。經檢定分析後,本文就各實證參數之經濟意涵加以闡示,最後並提出結論以及未來研究之方向。
本文透過月資料之群集分析,顯示夏月相對於非夏月之群集差異與台電公司現行季節電價夏月與非夏月之月份相一致,證實台電公司季節電價月份劃分之合理性。其次,透過ARIMA時間序列建立之短期電力需求預測模型,經實證結果顯示:電燈與電力用戶別之售電量均逐年增加,預測民國93年1月至民國99年12月,電燈用戶之年售電量平均成長率為3.33%、電力用戶為3.23%。再者,利用複迴歸模型進行實證分析之結果發現:(一)影響售電量之主要變數為溫度。惟因電燈用戶每隔兩月抄表一次,與電力用戶按月抄表之作業方式不同,故電燈用戶每月售電量係受前期(月)溫度影響,而電力用戶則受當期(月)溫度影響。(二)各用戶別之總電費收入與售電量有明顯相關,且經估算出各月售電量之電費收入彈性顯示:電燈用戶約為0.5,電力用戶約為1。由於總電費收入為總售電量與平均電價之乘積,故電燈用戶之電費收入增加1% 時,其售電量僅增加0.5%,顯示總電費的收入增加係有部分來自於平均電價的提高;換言之,就電燈用戶別而言,其電費收入增減變化之百分比除了會受到售電量增減幅度之影響外,亦反映了平均電價變化的情形。同理,對電力用戶來說,其各月售電量之電費收入彈性接近於1,表示電費收入變化1% 時,售電量亦增加1%,即電費收入之增減變化比例主要受到售電量之同向等幅變化所影響。
至於各用戶別之電費收入方面,電燈與電力兩類用戶自民國88年初至91年底四年期間均有逐年增加之趨勢,惟電力用戶之年增加幅度有隨時間遞減之現象,且歷年大抵以7-10月份較高,2月份最低。此外,影響用戶別電費收入之解釋變數中,各類用戶之售電量最為顯著,其參數值係隱示每增加一度售電量對其電費收入之影響。其中,電燈用戶之估計參數值為2.69,而電力用戶則為1.35。再者,由其電費收入之售電量彈性係數可以發現:電燈用戶約為1.2,電力用戶約為0.7,顯示電燈用戶總售電量增加1%時,總電費收入增加的幅度大於1%,而電力用戶則相反。推估電力用戶此一彈性係數較電燈用戶低之原因在於:電力用戶與電燈用戶之電價結構不同,前者係採需量電費與能量電費之兩部電價制,而後者僅包含流動電費之一部電價。最後,實證結果亦顯示電力系統之尖峰負載與負載率會影響電費收入,惟其影響幅度不大。 / A Study on Customer-by-Category Energy Sales and Power Sales Revenue Model: The Case of Taiwan Power Company
Abstract
The main purposes of this study are to examine the rationality of the seasonal pricing scheme defined by summer and non-summer months and to identify economic factors influencing customer-by-category energy sales and power sales revenue, utilizing the data of Taiwan Power Company (Taipower) as an empirical case. In order to achieve this objective, the cluster analysis from the perspective of load pattern and cost pattern are examined respectively to see if the seasonal pricing scheme has statistical meaning in its pattern differences in terms of summer vs. non-summer season. Second, two economic models including time-series analysis and multiple regression equations are formulated for the empirical case study. The subtotal energy sales and the subtotal power sales revenue by different type of customer categories, i.e. lighting and industrial customers, are set to be the explained variables. Data from January 1999 to December 2002 are collected for modeling simulation tests. The economic meanings and policy implications of the modeling results are elaborated on. And conclusions with directions for further research are presented.
Through the cluster analysis utilizing monthly data within the time frame mentioned above, empirical research results on the grouping cluster of summer vs. non-summer months shows a consistent trend with those defined by Taipower’s present seasonal pricing scheme. Second, the empirical results of ARIMA time-series model show that the forecasted energy sales of both lighting and industrial customers will be gradually increasing through January 2004 to December 2010, and the average annual growth rate of energy sales for the lighting customer is 3.33%, and for the industrial customer is 3.23%. On the other hand, the empirical research results through the multiple regression equations show that the main factor affecting the energy sales is temperature. Due to the different time schedules for reading electricity meters between the lighting customer and the industrial customer, i.e. the time interval for reading the meter of lighting customers is every two months and for industrial customers is every month, the monthly energy sales of the lighting customer are directly related to the temperature of the previous month, while the monthly sales of the industrial customer are directly related to the temperature of the present month. In addition, for each type of customers, there is an obvious correlation between the total power sales revenue and the total energy sales. Furthermore, the estimated elasticity of the total power sales revenue versus total energy sales is about 0.5 for the lighting customer, and about 1 for the industrial customer.
Since the total power sales revenue is the product of total energy sales times the average electricity price, when the total power sales revenue increases 1% with the total energy sales only increases 0.5%, it implies that the increase of total power sales revenue not just only comes from the increase of energy sales, but also partially affected by the increase of average electricity price. Similarly, for the industrial customer, when the elasticity of their monthly total power sales revenue versus total energy sales is close to 1, it implies that when the total power sales revenue increases 1%, the total energy sales also increase about 1%. In other words, the change of percentage of the total power sales revenue is mostly attributed to the variation of total energy sales, not because of the average electricity price.
As for the simulation results of the total power sales revenue, those of the lighting and industrial customers are both gradually increasing between the years 1999 to 2002. However, the increasing pace of the industrial customer tended to slow down. Moreover, both types of the customers possess a similar trend that their total power sales are higher in statistical meaning for the months from July to October, and lower for February, for those above three years. Besides, among the variables affecting each type of customer’s power sales revenue, the energy sales is the most significant one, its parameter implies that whenever the total energy sales increases one unit, i.e. one kwh, it would affect the total power sales revenue by that amount equivalent to the figure of the parameter. According to the empirical results, the estimated parameter mentioned-above of the lighting customer is 2.69, and 1.35 of the industrial customer respectively. That implies one kwh unit price for the lighting customer is 2.69 N.T. dollars, and 1.35 N.T. dollars for the industrial customer. Moreover, from the elasticity of the total energy sales versus the total power sales revenue, it shows that the elasticity of the lighting customer is around 1.2, and the elasticity of the industrial customer is around 0.7. The underlining reason of the difference between the two figures could be that the electricity pricing structure of the lighting and industrial customers are quite different. The industrial customer is charged by two-part tariff including a demand charge for the capacity use and an energy charge for the kwh use. While the lighting customer is charged simply by a single rate, i.e. the energy use. Finally, the empirical results also show that the magnitude of the peak load and the load factor of the whole electricity system also affect the total power sales revenue of each type of the customer, though with much less effect.
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應用kNN文字探勘技術於分析新聞評論 影響股價漲跌趨勢之研究 / The Study of Analyzing Comments of News for Influence of Stock Price Trends Prediction by Using Knn Text Mining詹智勝, Chan, Chih Sheng Unknown Date (has links)
在網際網路快速發展下,大量使用者在獲取知識與新聞的管道,已由傳統媒體轉移到網路上。網路活動下使用者互動後所留下的訊息,也就是網路口碑,也逐漸受到重視。而隨著經濟發展,國人在固定薪資下無法負擔高房價、高物價的生活,如何透過投資理財來增加自身財富,已是非常普遍,其中又以股市投資為大眾所重視之途徑。
網路新聞的發布,除了具有網路的即時性外,配合使用者閱讀內化後所留下的評論,應含有比網路新聞本身內容更多的資訊,投資者便可藉此找尋隱含之中大量市場消息與資訊。
本研究為了在龐大的資料量中,幫助使用者挖掘其背後之涵義,進而提供投資預測,將蒐集網路新聞及其閱讀者評論共1068篇,並分為訓練資料與測試資料,使用文字探勘及相關技術做前處理,再透過kNN分群技術,計算訓練資料文件間相似度,將大量未知資料依其相似度做分群後,利用歷史股價訊息對群集結果之特徵分析解釋之並建立預測模型,最後透過測試資料將模型分群結果進行評估,進而對股價趨勢做出預測。 / With the rapid development of the Internet, the way of user access to knowledge and news transfer from traditional media to the network. Internet word-of-mouth, the message generated from users' interaction on internet, attracts more and more people's attention. With economic development, people in the fixed salary cannot afford high prices and high price in live. People increase their own wealth through investment is very common, among which the stock market is the way to public attention.
Internet news has the immediacy of the Internet. And the comments left with the user to read the internalization should contain more information than the Internet news. Investors can find the market news and information by Internet news and comments.
In this study, in order to help the user to find the meaning behind the huge amount of data, and thus provide investment forecast. We will collect 1068 of internet news and reader reviews to divide into training data and test data using text mining and related technologies to do the pre-treatment, and then calculate the similarity between the training data by kNN, a lot of unknown data according to their similarity clustering. Cluster through the historical share price analysis and modeling. Finally, the model clustering results were evaluated through the test data to predict price trends. The prediction model from training data clustering, use test data to do the evaluation found: k = 15, the similarity threshold value = 0.05, cluster the results of the F-measure performance up to 56% rise in the cluster. K values and the similarity threshold will be adjusted to obtain the most favorable results of the model
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Obésité abdominale et autres déterminants du risque cardiométabolique dans deux populations urbaines noires apparentées : Port-au-Prince (Haïti) et Cotonou (Bénin)El Mabchour, Asma 02 1900 (has links)
L’obésité est un problème de santé publique reconnu. Dans la dernière décennie l’obésité abdominale (OA) a été considérée comme une maladie métabolique qui contribue davantage au risque de diabète et de maladies cardiovasculaires que l’obésité générale définie par l’indice de masse corporelle. Toutefois, dans les populations d’origine africaine, la relation entre l’OA et les autres biomarqueurs de risque cardiométabolique (RCM) demeure obscure à cause du manque d’études chez ces populations et de l’absence de valeurs-seuils spécifiques pour juger d’une OA. Cette étude visait à comparer la prévalence des biomarqueurs de RCM (OA, hypertension artérielle, hyperglycémie, dyslipidémie, résistance à l'insuline et inflammation pré-clinique) chez les Béninois de Cotonou et les Haïtiens de Port-au-Prince (PAP), à étudier l’association de l’OA avec les autres biomarqueurs de RCM, à documenter le rôle du niveau socio-économique (NSE) et du mode de vie dans cette association et à ’identifier les indicateurs anthropométriques de l’OA -tour de taille (TT) et le ratio TT/hauteur (TT/H)- et les seuils qui prédisent le mieux le RCM à Cotonou et à PAP.
Il s’est agi d’une analyse de données transversales chez 452 adultes (52 % hommes) apparemment en bonne santé, âgés de 25 à 60 ans, avec 200 sujets vivant à Cotonou (Bénin) et 252 sujets à PAP (Haïti). Les biomarqueurs de RCM considérés étaient : le syndrome métabolique (SMet) d’après les critères harmonisés de 2009 et ses composantes individuelles - une OA à partir d’un TT ≥ 94cm chez les hommes et ≥ 80cm chez les femmes, une hypertension, une dyslipidémie et une hyperglycémie; la résistance à l’insuline définie chez l’ensemble des sujets de l’étude à partir du 75e centile de l’Homeostasis Model Assessment (HOMA-IR); un ratio d’athérogénicité élevé (Cholestérol sérique total/HDL-Cholestérol); et l’inflammation pré-clinique mesurée à partir d’un niveau de protéine C-réactive ultrasensible (PCRus) entre 3 et 10 mg/l. Le ratio TT/H était aussi considéré pour définir l’OA à partir d’un seuil de 0,5. Les données sur les habitudes alimentaires, la consommation d’alcool, le tabagisme, les caractéristiques sociodémographiques et les conditions socio-économiques incluant le niveau d’éducation et un proxy du revenu (basé sur l’analyse par composante principale des biens et des possessions) ont été recueillies au moyen d’un questionnaire. Sur la base de données de fréquence de consommation d’aliments occidentaux, urbains et traditionnels, des schémas alimentaires des sujets de chaque ville ont été identifiés par analyse typologique. La validité et les valeurs-seuils de TT et du ratio TT/H prédictives du RCM ont été définies à partir des courbes ROC (Receiver Operating Characteristics).
Le SMet était présent chez 21,5 % et 16,1 % des participants, respectivement à Cotonou et à PAP. La prévalence d’OA était élevée à Cotonou (52,5 %) qu’à PAP (36%), avec une prévalence plus élevée chez les femmes que chez les hommes. Le profil lipidique sérique était plus athérogène à PAP avec 89,3 % d’HDL-c bas à PAP contre 79,7 % à Cotonou et un ratio CT/HDL-c élevé de 73,4 % à PAP contre 42 % à Cotonou. Les valeurs-seuils spécifiques de TT et du TT/H étaient respectivement 94 cm et 0,59 chez les femmes et 80 cm et 0,50 chez les hommes. Les analyses multivariées de l’OA avec les biomarqueurs de RCM les plus fortement prévalents dans ces deux populations montraient que l’OA était associée à un risque accru de résistance à l’insuline, d’athérogénicité et de tension artérielle élevée et ceci, indépendamment des facteurs socio-économiques et du mode de vie. Deux schémas alimentaires ont émergé, transitionnel et traditionnel, dans chaque ville, mais ceux-ci ne se révélaient pas associés aux biomarqueurs de RCM bien qu’ils soient en lien avec les variables socio-économiques.
La présente étude confirme la présence de plusieurs biomarqueurs de RCM chez des sujets apparemment sains. En outre, l’OA est un élément clé du RCM dans ces deux populations. Les seuils actuels de TT devraient être reconsidérés éventuellement à la lumière d’études de plus grande envergure, afin de mieux définir l’OA chez les Noirs africains ou d’origine africaine, ce qui permettra une surveillance épidémiologique plus adéquate des biomarqueurs de RCM. / Obesity is recognized as a major public health problem. In the last decade abdominal obesity (AO) was considered as a metabolic disorder which further contributes to the risk of diabetes and cardiovascular disease than the general obesity defined by body mass index. However, in African origin population groups, the relationship between AO and other cardiometabolic risk (CMR) biomarkers remained unclear because of the lack of studies in these population groups and the lack of specific cut-off values to define AO. This study aimed to compare the prevalence of CMR biomarkers (OA, hypertension, hyperglycemia, dyslipidemia, insulin resistance and subclinical inflammation) in Beninese from Cotonou and Haitians from Port-au-Prince (PAP), to assess the association between AO and other CMR biomarkers in relation to Cotonou and PAP participants’ socioeconomic and lifestyle parameters and to define anthropometric indicators of AO -waist circumference (WC) and waist-to-height ratio (WHtR)- and specific thresholds that best predict the CMR in both Cotonou and PAP.
The cross-sectional study included 452 apparently healthy adults (52 % men), aged 25-60 years, 200 subjects from Cotonou (Benin) and 252 subjects from PAP (Haiti). The CMR biomarkers were: the metabolic syndrome (MetS) according to the harmonized criteria of 2009, its individual components - AO defined by a WC ≥ 94cm in men and ≥ 80 cm in women, hypertension, dyslipidemia and hyperglycemia - Insulin resistance was set at the 75th centile of Homeostasis Model Assessment (HOMA-IR) for the whole sample of subjects. High atherogenicity index (total serum cholesterol/HDL-Cholesterol), subclinical inflammation according to high-sensitivity C-reactive protein (hsCRP) concentration between 3 to 10 mg/L was also assessed. WHtR from a cut-off point of 0.5 was also considered to assess AO. Data on dietary habits, alcohol consumption, tobacco, sociodemographic and socioeconomic status, including education level and a proxy of income (based on principal component analysis of property and possessions) were documented by a questionnaire. Dietary patterns were generated from Western, urban and traditional food frequency in each city by cluster analysis. Receiver Operating Characteristic (ROC) curves were used to assess the performance of specific WC and WHtR cut-offs to predict the CMR.
MetS was present in 21.5 % and 16.1 % of participants in Cotonou and PAP respectively. AO was higher in Cotonou (52.5 %) than in PAP (36 %) with higher prevalence in women than in men. The serum lipid profile was more atherogenic in PAP with 89.3 % of low HDL-C in PAP comparing to 79.7 % in Cotonou and high seum TC / HDL-C ratio of 73.4 % in PAP versus 42 % in Cotonou. The specific WC and WHtR cut-off values were respectively 94 cm and 0.59 in women and 80cm and 0.50 in men. Multivariate analysis of AO with the most prevalent CMR biomarkers in these two population groups showed that AO was associated with increased risk of insulin resistance, high atherogenic index and high blood pressure, irrespective of socioeconomic and lifestyle factors. Two dietary patterns were defined: transitional and traditional in each city, but these were not associated with the CMR biomarkers although they were related to socioeconomic variables.
This study confirms the presence of several CMR biomarkers in apparently healthy subjects. Additionally, AO was a key element of the CMR in both population groups. However, current WC thresholds should be reconsidered in light of larger studies to better define AO among Black African groups, which will improve the epidemiological surveillance of the CMR biomarkers.
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Reprodukční zdraví a umělá potratovost v Latinské Americe a Karibiku / Reproductive health and induced abortion in Latin America and the CaribbeanKomrsková, Lucie January 2014 (has links)
Reproductive health and induced abortion in Latin America and the Caribbean Abstract The objective of this study is to give a comprehensive overview of the reproductive health of the population living in Latin America and the Caribbean, and to evaluate the level of induced abortion in the region at the same time. In the theoretical part of the study the term reproductive health is defined and indicators evaluating its level are described. As well the difference between safe and unsafe abortion is explained and the state of abortion law is expounded in this part. Next part is devoted to the promotion of family planning programs. In the analytical part Latin American and Caribbean countries are divided into four groups by using cluster analysis. Within each group one selected country is characterized in more detail. Indicators entering into the analysis show the level of reproductive health, the level of fertility and the economic performance of countries in the early 21st century. In the part related to the induced abortion rate in the region is discovered that despite the fact that in Latin America and the Caribbean there is one of the highest levels of contraceptive prevalence, there is also the highest level of induced abortion in the world. In the last part of the study the relationship between level of...
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Shluková analýza rozsáhlých souborů dat: nové postupy založené na metodě k-průměrů / Cluster analysis of large data sets: new procedures based on the method k-meansŽambochová, Marta January 2005 (has links)
Abstract Cluster analysis has become one of the main tools used in extracting knowledge from data, which is known as data mining. In this area of data analysis, data of large dimensions are often processed, both in the number of objects and in the number of variables, which characterize the objects. Many methods for data clustering have been developed. One of the most widely used is a k-means method, which is suitable for clustering data sets containing large number of objects. It is based on finding the best clustering in relation to the initial distribution of objects into clusters and subsequent step-by-step redistribution of objects belonging to the clusters by the optimization function. The aim of this Ph.D. thesis was a comparison of selected variants of existing k-means methods, detailed characterization of their positive and negative characte- ristics, new alternatives of this method and experimental comparisons with existing approaches. These objectives were met. I focused on modifications of the k-means method for clustering of large number of objects in my work, specifically on the algorithms BIRCH k-means, filtering, k-means++ and two-phases. I watched the time complexity of algorithms, the effect of initialization distribution and outliers, the validity of the resulting clusters. Two real data files and some generated data sets were used. The common and different features of method, which are under investigation, are summarized at the end of the work. The main aim and benefit of the work is to devise my modifications, solving the bottlenecks of the basic procedure and of the existing variants, their programming and verification. Some modifications brought accelerate the processing. The application of the main ideas of algorithm k-means++ brought to other variants of k-means method better results of clustering. The most significant of the proposed changes is a modification of the filtering algorithm, which brings an entirely new feature of the algorithm, which is the detection of outliers. The accompanying CD is enclosed. It includes the source code of programs written in MATLAB development environment. Programs were created specifically for the purpose of this work and are intended for experimental use. The CD also contains the data files used for various experiments.
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