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Seleção de variáveis para definição de unidades de manejo através da lógica fuzzy C-means / Selection of variables for definition of management units by fuzzy c-means logicSobjak, Ricardo 09 April 2012 (has links)
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Previous issue date: 2012-04-09 / The agricultural production area has important information to understand the response of a
crop yield. Precision agriculture helps the farmers on acquiring and treating in correct way
the variations found in the area. Management zones (MZ) provide the precision agriculture
implementation in a viable and relatively economical way, since they represent
homogeneous regions, which can be treated differently. Thus, this trial aimed at generating
MZ with different numbers of variables using fuzzy C-means algorithm, based on attributes
spatially correlated with crop yield. The objective was to evaluate the relative efficiency of
each management zone and verify if the different ways of variable compositions differ in the
generation of MZ. Fifteen designs of MZ were generated and divided from two to five
classes, based on attributes as: copper, silt, clay and altitude, which were correlated with
crop yield. The copper variable showed the highest spatial correlation with crop yield, which
promoted the generation of MZ with good results of relative efficiency and good separation of
data among the classes. The relative efficiency did not present in an orderly manner,
increasing or decreasing according to the number of variables used in division of MZ. The
delineated MZ was based on variables as copper and clay and divided into five classes, so, it
showed the highest relative efficiency / A área de produção agrícola contém informações importantes para se entender a resposta
quanto à produtividade de uma cultura. A agricultura de precisão proporciona aos
agricultores adquirirem e tratarem as variações encontradas na área de forma adequada.
Unidades de manejo (UM) proporcionam a implantação da agricultura de precisão de forma
viável e relativamente mais econômica, representando regiões homogêneas, que podem ser
tratadas de forma diferenciada. Este trabalho consistiu em gerar unidades de manejo com
diferentes números de variáveis através do algoritmo fuzzy C-means, baseando-se em
atributos correlacionados espacialmente com a produtividade. O objetivo é avaliar a
eficiência relativa de cada unidade de manejo e verificar se os diferentes modos de
composição de variáveis se diferenciam na geração de UM. Geraram-se 15 delineamentos
de UM, divididos de 2 a 5 classes, baseando-se nos atributos cobre, silte, argila e altitude,
que foram correlacionados com a produtividade. A variável cobre teve a maior correlação
espacial com a produtividade, a qual proporcionou a geração de UM com bons resultados de
eficiência relativa e boa separação dos dados entre as classes. A eficiência relativa não se
apresentou de forma ordenada, crescente ou decrescente, quanto ao número de variáveis
utilizadas no delineamento em UM. A UM delineada a partir das variáveis Cu e argila,
dividida em cinco classes, foi a que apresentou maior eficiência relativa
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Seleção de variáveis para definição de unidades de manejo através da lógica fuzzy C-means / Selection of variables for definition of management units by fuzzy c-means logicSobjak, Ricardo 09 April 2012 (has links)
Made available in DSpace on 2017-05-12T14:48:35Z (GMT). No. of bitstreams: 1
Ricardo.pdf: 1705247 bytes, checksum: 435e22f6b6cf7bf51e60d35de482adba (MD5)
Previous issue date: 2012-04-09 / The agricultural production area has important information to understand the response of a
crop yield. Precision agriculture helps the farmers on acquiring and treating in correct way
the variations found in the area. Management zones (MZ) provide the precision agriculture
implementation in a viable and relatively economical way, since they represent
homogeneous regions, which can be treated differently. Thus, this trial aimed at generating
MZ with different numbers of variables using fuzzy C-means algorithm, based on attributes
spatially correlated with crop yield. The objective was to evaluate the relative efficiency of
each management zone and verify if the different ways of variable compositions differ in the
generation of MZ. Fifteen designs of MZ were generated and divided from two to five
classes, based on attributes as: copper, silt, clay and altitude, which were correlated with
crop yield. The copper variable showed the highest spatial correlation with crop yield, which
promoted the generation of MZ with good results of relative efficiency and good separation of
data among the classes. The relative efficiency did not present in an orderly manner,
increasing or decreasing according to the number of variables used in division of MZ. The
delineated MZ was based on variables as copper and clay and divided into five classes, so, it
showed the highest relative efficiency / A área de produção agrícola contém informações importantes para se entender a resposta
quanto à produtividade de uma cultura. A agricultura de precisão proporciona aos
agricultores adquirirem e tratarem as variações encontradas na área de forma adequada.
Unidades de manejo (UM) proporcionam a implantação da agricultura de precisão de forma
viável e relativamente mais econômica, representando regiões homogêneas, que podem ser
tratadas de forma diferenciada. Este trabalho consistiu em gerar unidades de manejo com
diferentes números de variáveis através do algoritmo fuzzy C-means, baseando-se em
atributos correlacionados espacialmente com a produtividade. O objetivo é avaliar a
eficiência relativa de cada unidade de manejo e verificar se os diferentes modos de
composição de variáveis se diferenciam na geração de UM. Geraram-se 15 delineamentos
de UM, divididos de 2 a 5 classes, baseando-se nos atributos cobre, silte, argila e altitude,
que foram correlacionados com a produtividade. A variável cobre teve a maior correlação
espacial com a produtividade, a qual proporcionou a geração de UM com bons resultados de
eficiência relativa e boa separação dos dados entre as classes. A eficiência relativa não se
apresentou de forma ordenada, crescente ou decrescente, quanto ao número de variáveis
utilizadas no delineamento em UM. A UM delineada a partir das variáveis Cu e argila,
dividida em cinco classes, foi a que apresentou maior eficiência relativa
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Seasonal Adjustment and Dynamic Linear ModelsTongur, Can January 2013 (has links)
Dynamic Linear Models are a state space model framework based on the Kalman filter. We use this framework to do seasonal adjustments of empirical and artificial data. A simple model and an extended model based on Gibbs sampling are used and the results are compared with the results of a standard seasonal adjustment method. The state space approach is then extended to discuss direct and indirect seasonal adjustments. This is achieved by applying a seasonal level model with no trend and some specific input variances that render different signal-to-noise ratios. This is illustrated for a system consisting of two artificial time series. Relative efficiencies between direct, indirect and multivariate, i.e. optimal, variances are then analyzed. In practice, standard seasonal adjustment packages do not support optimal/multivariate seasonal adjustments, so a univariate approach to simultaneous estimation is presented by specifying a Holt-Winters exponential smoothing method. This is applied to two sets of time series systems by defining a total loss function that is specified with a trade-off weight between the individual series’ loss functions and their aggregate loss function. The loss function is based on either the more conventional squared errors loss or on a robust Huber loss. The exponential decay parameters are then estimated by minimizing the total loss function for different trade-off weights. It is then concluded what approach, direct or indirect seasonal adjustment, is to be preferred for the two time series systems. The dynamic linear modeling approach is also applied to Swedish political opinion polls to assert the true underlying political opinion when there are several polls, with potential design effects and bias, observed at non-equidistant time points. A Wiener process model is used to model the change in the proportion of voters supporting either a specific party or a party block. Similar to stock market models, all available (political) information is assumed to be capitalized in the poll results and is incorporated in the model by assimilating opinion poll results with the model through Bayesian updating of the posterior distribution. Based on the results, we are able to assess the true underlying voter proportion and additionally predict the elections. / <p>At the time of doctoral defence the following papers were unpublished and had a status as follows: Paper 3: Manuscript; Paper 4: Manuscripts</p>
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BLOCK DESIGNS UNDER AUTOCORRELATED ERRORSShu, Xiaohua January 2011 (has links)
This research work is focused on the balanced and partially balanced incomplete block designs when observations within blocks are correlated. The topic for this dissertation was motivated by a problem in pharmaceutical research, when several treatments are allocated to individuals, and repeated measurements are taken on each individual. In that case, there is correlation among the observations taken on the same individual. Typically, it is reasonable to assume that the observations within individual close to each other are highly correlated than observations that are far away from each other. It is also reasonable to assume that the correlation between any two observations within each individual is same. We have characterized balanced and partially balanced incomplete block designs when observations within blocks are autocorrelated. In Chapter 3, we have provided an explicit expression for the average variance of estimated elementary treatment contrasts for designs obtained by Type I and II series of orthogonal arrays, under autocorrelated errors, and compared them with the corresponding balanced incomplete block designs with uncorrelated errors. The relative efficiency of balanced incomplete block design compared to the corresponding balanced incomplete block design obtained by Types I and II series of orthogonal array under autocorrelated errors does not depend on the number of treatments (v) and is an increasing function of the block size (k). When orthogonal arrays of Type I or Type II do not exist for a given number of treatments, we provided alternative partially balanced designs with autocorrelated errors. In Chapter 4, we rearranged the treatments in each block of symmetric balanced incomplete block designs and used them with autocorrelated error structure of the plots in a block. The C-matrix of estimated treatment effects under autocorrelation was given and the relative efficiency of symmetric balanced incomplete block designs with independent errors compared to the autocorrelated designs is given. In Chapter 5, we discussed the compound symmetry correlation structure within blocks. An explicit expression of the average variance of designs obtained by Type I and II series of orthogonal arrays and symmetric balanced incomplete block designs under compound symmetric errors has been provided and compared them with the corresponding balanced incomplete block designs with uncorrelated errors. Finally, the relative efficiencies of these designs with autocorrelated errors vs. compound symmetric error structure are given / Statistics
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複合估計方法在就診率之應用徐培原 Unknown Date (has links)
疾病就診率係針對固定期問內,患有疾病而到全民健康保險特約之各級醫療院所就診之人數予以統計,其分析可供規劃醫療保健服務與修訂全民健保制度之參據,因此應成為經常性之統計工作。本文以適合連續性調查的輪換抽樣設計為原則,運用調查當期及較早期之資訊以建搆複合估計式,並推導該估計式之期望值與變異數,據以此比較與簡單估計式之相對效率。為評估複合估計方法運用於疾病就診率之效益,遂選定某些疾病進行分析,並研究在何種權數組合下,複合估計式能減低變動情形及其相對效率。
關鍵字:疾病就診率、輪換抽樣法、複合估計式、相對效率 / The treatment rate is a statistical analysis of numbers of people who had taken treatment in the fixed period. It can be a reference of planning medical service, revising medical laws and so on. So its analysis is important and should be an occasionally statistical work. In this paper, we adopt rotation sampling method, combine current and earlier information to construct composite estimator, and derive its expected value and variance formula, so as to compare with simple estimator. To evaluate the benefit of adopting composite estimator on the treatment rate, we choose some diseases as objectives, and determine the optimal weighted parameter so that composite estimator can reduce the variance and its effects on the relative efficiency.
Key words: treatment rate, rotation sampling, composite estimator, relative efficiency
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Rendas petrolíferas e indicadores sociais municipais: uma análise de eficiência relativa / Oil windfalls and municipal social indicators: an analysis of relative efficiencyAndré Attilio Brasil Freitas 29 November 2013 (has links)
Em 1997, a chamada Lei do Petróleo instituiu novos critérios para a partilha das rendas petrolíferas com estados e municípios, elevando substancialmente a arrecadação dos entes federativos. De acordo com a teoria econômica os recursos naturais devem ser aplicados de forma eficiente em capital, visando o desenvolvimento socioeconômico do país. O objetivo deste trabalho é analisar se os royalties do petróleo, gás natural e outros hidrocarbonetos fluidos afetam a eficiência dos municípios no que se refere a determinados indicadores sociais. Esta análise foi feita em dois estágios. No primeiro estágio, estimaram-se escores de eficiência relativa com respeito à \"produção\" de indicadores sociais municipais pela metodologia da Análise de Envoltória de Dados (DEA, em inglês). No segundo estágio, uma regressão desses escores no valor em Reais de royalties recebidos por cada município (além de outras variáveis de controle) avaliou que, a níveis estatisticamente significativos, pode-se afirmar que os royalties têm um impacto negativo na eficiência da \"produção\" desses indicadores. / In 1997, the law known as Oil Act established new criteria regarding the distribution of the oil income to States and Municipalities, substantially raising the incomings of the Federal entities. According to the economic theory natural resources should be applied efficiently in the capital, targeting the country\'s socioeconomic development. This work aims to analyze whether the royalties from the production of oil, natural gas and other fluid hydrocarbons affect the efficiency of Municipalities with regard to certain social indicators. This analysis was done in two stages. In the first stage, relative efficiency scores were estimated with respect to the \"production\" of municipal social indicators by the methodology of Data Envelopment Analysis (DEA). In the second stage, a regression of these scores in Reais of royalties received by each Municipality (besides other variables of control) assessed that, at statistically significant levels, it may be asserted that the royalties have a negative impact upon the efficiency of the \"production\" of these indicators.
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GestÃo do conhecimento no planejamento de contrataÃÃes de soluÃÃes em TI em InstituiÃÃes Federais de Ensino Superior do Brasil: um diagnÃstico usando anÃlise envoltÃria de dados. / Knowledge management in planning contracting IT solutions in Federal Institutions of Higher Education of Brazil:a diagnosis using Data Envelopment AnalysisBeatriz Duarte Lima de AraÃjo 12 December 2016 (has links)
nÃo hà / Para a atual conjuntura social, com rÃpidas transformaÃÃes em todas as Ãreas, à importante que o conhecimento esteja integrado aos processos de negÃcios da organizaÃÃo. As instituiÃÃes federais de ensino superior necessitam de uma visÃo especial quanto à implantaÃÃo dos processos e prÃticas de GestÃo do Conhecimento (GC), devido Ãs suas particularidades em seu ambiente de ensino e tambÃm em sua Ãrea administrativa. O planejamento de aquisiÃÃes de Tecnologia da InformaÃÃo (TI) na IFES carece de ferramentas de apoio, que possibilitem a otimizaÃÃo e melhoria de suas atividades. Assim sendo, este estudo tem como objetivo geral analisar a eficiÃncia relativa das IFES do Brasil quanto ao uso da gestÃo do conhecimento no planejamento das contrataÃÃes de soluÃÃes de TI, utilizando o mÃtodo de AnÃlise EnvoltÃria de Dados (DEA), e o modelo Charnes, Cooper e Rhodes (CCR), orientados aos resultados. Ademais, sÃo apresentados os conceitos de GC, os principais modelos teÃricos acerca do tema, alguns modelos de diagnÃstico de GC voltados para a AdministraÃÃo pÃblica e suas principais prÃticas, a relaÃÃo com a Tecnologia InformaÃÃo, uma contextualizaÃÃo acerca do planejamento das contrataÃÃes de TI e a GC, bem como os principais conceitos relacionados ao mÃtodo DEA. O estudo, por ser de levantamento, caracteriza-se como sendo do tipo survey, com abordagem quantitativa. No tocante aos objetivos à uma pesquisa descritiva, no qual foi aplicado questionÃrio baseado no Instrumento para AvaliaÃÃo da GestÃo do Conhecimento na AdministraÃÃo PÃblica, modelo este criado por Batista (2006). O instrumento foi aplicado aos gestores das Ãreas de TI das 103 instituiÃÃes Federais de Ensino Superior do Brasil. Das instituiÃÃes Ãs quais o questionÃrio foi enviado, 86 enviaram as informaÃÃes solicitadas. Na anÃlise descritiva sÃo apresentados os resultados da pesquisa mostrando a caracterizaÃÃo das IFES respondentes, como funciona o processo de planejamento das contrataÃÃes de soluÃÃes de TI nas IFES pesquisadas, as iniciativas de gestÃo do conhecimento e prÃticas de gestÃo do conhecimento usadas como suporte ao planejamento das contrataÃÃes de TI das IFES que responderam à pesquisa. Dentre as 86 instituiÃÃes analisadas, de acordo com o software Frontier Analyst, 57 foram consideradas eficientes e 29 IFES foram classificadas como ineficientes. SÃo tambÃm apresentados os benchmarkings, os quais as 29 IFES consideradas ineficientes devem tomar como referÃncia para melhorar sua eficiÃncia no planejamento das contrataÃÃes de TI, bem como as potenciais melhorias que as IFES devem avaliar nos fatores de entrada e saÃda analisados, para que possam melhorar sua eficiÃncia relativa no que diz respeito ao uso da gestÃo do conhecimento como suporte ao planejamento das contrataÃÃes de soluÃÃes de TI. / In the present social conjuncture, with fast transformations in all areas, is important that the knowledge and the business tactics work together in the organization. Federal institutions of higher education need a special view about the implantation and use of knowledge management, because of their peculiarities of teaching and governance. The acquisition planning of information technology lacks the support that woud enable a great improvement in the activities. This study has as general goal analyze the efficiency of IFES in Brazil concerning the knowledge management in information technology hiring, using for this purpose the method Data Envelopment Analysis (DEA), and Charnes, Cooper e Rhodes (CCR) model results-oriented. Moreover are presented the notion of KM, the leading theorists models about the theme, some types of diagnosis of KM related for public administration, as well as the notion of DEA. The study is the kind survey with quantitative approach. Regarding the goals is a descriptive research, applying a questionnaire based in the model created for Batista (2006). The questionnaire was applied to the managers of IT of 103 organizations of higher education in Brazil. Among the institutions to whom the questionnaire were sent, 86 responded. In the descriptive analysis are presented the results of the research showing the characterization of the IFES, like how the process hiring of technology solutions works, and how the initiatives of knowledge management are used to give suport to them. Among the 86 institutions analyzed according the Software Frontier Analyst, 57 were regarded efficient and 29 were regarded as not efficient. Are presented the benchmarkings, wich the inefficients IFES must consider for the improvement of their planning in IT, as well as they ought to evaluate the factors of entry and output analyzeds always with the goal of advance in the use of knowledge of management as suport for the hiring of IT solutions.
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Estudo sobre a aplica??o da an?lise da efici?ncia relativa utilizando a metodologia DEA em organiza??o militar de sa?de: o caso da Odontocl?nica Central do Ex?rcito / Study on the application of relative efficiency analysis using DEA methodology for Military health organizations: the case of the Central Army Orthodontic ClinicSouza, Marlone Wilson 06 September 2006 (has links)
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Previous issue date: 2006-09-06 / This study addresses themes arising from studies on performance analysis, specifically
considering the analysis of relative efficiency, through the use of the model known as DEA
(Data Envelopment Analysis), as introduced by Charnes, Cooper and Rhodes (1978) and
based on the first studies of Farrel (1957). The technique was applied to a military health
organization, the Central Army Orthodontic Clinic, aiming to propose and describe a
methodology which would be capable of evaluating the relative efficiency of the clinics which
make up the organization, identifying its efficient and inefficient units. The data used was
obtained form the administration department of the Central Army Orthodontic clinic
throughout 2005. The model conceived by Charnes, Cooper and Rhodes (1978) is known as
CCR and input was adopted for orientation, as the maintenance of output was used as a base
searching for efficiency through the minimization of economic supplies. To put the DEA
model into action, the SIAD (Integrated System of support for decision-making) programme
was used, using as economic supplies the direct materials and the relevant indirect costs,
considering income generated and patients treated as the product in 11 DMU (clinics). Two
distinct models were created, initially comparing the economic supplies and the income
(representing the financial component) and finally the same economic supplies with patients
treated (representing a non-financial component), describing in each case the efficient and
inefficient DMU, as well as the degree of comparison of each case. It was concluded that it is
possible to evaluate the relative efficiency of DMU in an organization of this nature, and that
it is feasible to use DEA as a tool to calculate the proportion of subsidies in the decision
making process, also opening up the possibility for other studies in military organizations
which deal with war related activities and the operational use of the armed forces. / Esta pesquisa abordou conceitos advindos de estudos sobre an?lise de desempenho,
considerando especificamente a an?lise da efici?ncia relativa, atrav?s da utiliza??o do modelo
denominado DEA (Data Envelopment Analysis), introduzido por Charnes, Cooper e Rhodes
(1978) baseados nos primeiros estudos de Farrel (1957). A aplica??o da t?cnica foi realizada
em organiza??o militar de sa?de, a Odontocl?nica Central do Ex?rcito, a fim de propor e
descrever uma metodologia capaz de prover a avalia??o da efici?ncia relativa das cl?nicas que
integram a organiza??o, identificando as suas unidades eficientes e/ou ineficientes. Foram
utilizados os dados obtidos junto ? administra??o da Odontocl?nica Central do Ex?rcito no
exerc?cio de 2005. O modelo concebido por Charnes, Cooper e Rhodes (1978), conhecido na
literatura por CCR, foi escolhido e adotou-se a orienta??o input, j? que se tomou por base a
manuten??o dos outputs buscando-se a efici?ncia atrav?s da minimiza??o dos insumos. Para
rodar a modelagem DEA foi selecionado o programa SIAD (sistema integrado de apoio ?
decis?o), carregando como insumos os materiais diretos e os custos indiretos relevantes e
considerando como produtos a receita faturada e os pacientes atendidos em 11(onze) DMU
(cl?nicas). Foram criados dois modelos distintos, inicialmente contrapondo-se esses insumos e
a receita (componente de natureza financeira) e posteriormente os mesmos insumos com
pacientes atendidos (componente de natureza n?o financeira), descrevendo-se as DMU
eficientes e ineficientes em cada caso, bem como a magnitude comparativa em cada situa??o.
Concluiu-se que ? poss?vel avaliar a efici?ncia relativa das DMU em organiza??o dessa
natureza, demonstrando assim, como ? fact?vel o emprego da ferramenta DEA para
proporcionar subs?dios no processo decis?rio, abrindo um campo para outras pesquisas em
organiza??es militares que lidam com a atividade b?lica e com o emprego operacional da
for?a terrestre.
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Rendas petrolíferas e indicadores sociais municipais: uma análise de eficiência relativa / Oil windfalls and municipal social indicators: an analysis of relative efficiencyFreitas, André Attilio Brasil 29 November 2013 (has links)
Em 1997, a chamada Lei do Petróleo instituiu novos critérios para a partilha das rendas petrolíferas com estados e municípios, elevando substancialmente a arrecadação dos entes federativos. De acordo com a teoria econômica os recursos naturais devem ser aplicados de forma eficiente em capital, visando o desenvolvimento socioeconômico do país. O objetivo deste trabalho é analisar se os royalties do petróleo, gás natural e outros hidrocarbonetos fluidos afetam a eficiência dos municípios no que se refere a determinados indicadores sociais. Esta análise foi feita em dois estágios. No primeiro estágio, estimaram-se escores de eficiência relativa com respeito à \"produção\" de indicadores sociais municipais pela metodologia da Análise de Envoltória de Dados (DEA, em inglês). No segundo estágio, uma regressão desses escores no valor em Reais de royalties recebidos por cada município (além de outras variáveis de controle) avaliou que, a níveis estatisticamente significativos, pode-se afirmar que os royalties têm um impacto negativo na eficiência da \"produção\" desses indicadores. / In 1997, the law known as Oil Act established new criteria regarding the distribution of the oil income to States and Municipalities, substantially raising the incomings of the Federal entities. According to the economic theory natural resources should be applied efficiently in the capital, targeting the country\'s socioeconomic development. This work aims to analyze whether the royalties from the production of oil, natural gas and other fluid hydrocarbons affect the efficiency of Municipalities with regard to certain social indicators. This analysis was done in two stages. In the first stage, relative efficiency scores were estimated with respect to the \"production\" of municipal social indicators by the methodology of Data Envelopment Analysis (DEA). In the second stage, a regression of these scores in Reais of royalties received by each Municipality (besides other variables of control) assessed that, at statistically significant levels, it may be asserted that the royalties have a negative impact upon the efficiency of the \"production\" of these indicators.
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Performance of Imputation Algorithms on Artificially Produced Missing at Random DataOketch, Tobias O 01 May 2017 (has links)
Missing data is one of the challenges we are facing today in modeling valid statistical models. It reduces the representativeness of the data samples. Hence, population estimates, and model parameters estimated from such data are likely to be biased.
However, the missing data problem is an area under study, and alternative better statistical procedures have been presented to mitigate its shortcomings. In this paper, we review causes of missing data, and various methods of handling missing data. Our main focus is evaluating various multiple imputation (MI) methods from the multiple imputation of chained equation (MICE) package in the statistical software R. We assess how these MI methods perform with different percentages of missing data. A multiple regression model was fit on the imputed data sets and the complete data set. Statistical comparisons of the regression coefficients are made between the models using the imputed data and the complete data.
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