The aim of this study has been to compare the accuracy of prognosis tools and how well they do with regards to seasonal variation and known deviations in order to decide which method is more suitable for companies with the goal of optimizing their staffing. The study has used Systembolaget as a case to compare two methods of prognosis. Data has been retrieved from Systembolaget and includes the company's sales. The methods that have been compared are Holt-Winters method and regression analysis. This has been done by applying the methods in order to generate a forecast and then evaluating the result through MAPE. Application of these methods was done with Excel and SPSS. The study showed that, under the present circumstances, both methods on average gave equally accurate forecasts. Holt-Winter's method however, forecasted more accurately week by week, while the regression analysis projection on average yielded almost equal percentage error. The conclusion that was generated by the study was that Holt-Winter's method is preferable for companies with this type of sale if the purpose is to generate a weekly accurate forecast. On the other hand, the conclusion may vary if methods are optimized and more data is available. / Målet med denna undersökning har varit att jämföra noggrannheten hos prognostiseringsverktyg och hur bra dessa tar hänsyn till säsongsvariationer och kända avvikelser för att avgöra vilket verktyg som är lämpligast för företag med som vill optimera sin bemanning. Studien har använt Systembolaget som fall för att jämföra två metoder för prognostisering. Data har hämtats från Systembolaget och omfattar företagets försäljning. Metoderna som har jämförts har varit Holt-Winters metod och Regressionsanalys. Detta har utförts genom att tillämpa metoderna för att få ut en prognos och sedan utvärdera resultatet genom MAPE. Tillämpningen av dessa metoder skedde via Excel och SPSS. Studien visade att under de befintliga omständigheterna gav båda metoder i snitt lika noggranna prognoser. Holt-Winters metod prognostiserade dock noggrannare vecka för vecka, medan regressionsanalysens prognos i snitt gav nästan lika stort procentuellt fel. Slutsatsen som genererades genom studien var att Holt-Winters metod är att föredra för företag med denna typ av försäljning om syftet är att få en så noggrann prognos för varje vecka. Däremot kan slutsatsen variera om metoderna optimeras och mer data finns tillgänglig.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-03-02T22:51:53Z No. of bitstreams: 1 TiagoDosSantosBezerra_DISSERT.pdf: 2629795 bytes, checksum: 9ffd5ffe3a05204b53801a61891c5393 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-03-04T00:16:01Z (GMT) No. of bitstreams: 1 TiagoDosSantosBezerra_DISSERT.pdf: 2629795 bytes, checksum: 9ffd5ffe3a05204b53801a61891c5393 (MD5) / Made available in DSpace on 2016-03-04T00:16:01Z (GMT). No. of bitstreams: 1 TiagoDosSantosBezerra_DISSERT.pdf: 2629795 bytes, checksum: 9ffd5ffe3a05204b53801a61891c5393 (MD5) Previous issue date: 2014-06-10 / Com o crescimento da demanda de tr?fego de dados nas redes de terceira gera??o (3G), as operadoras de telefonia m?vel t?m atentado para o direcionamento dos recursos em infraestrutura nos locais onde se identifica maior necessidade. O direcionamento desses investimentos tem o objetivo de manter a qualidade do servi?o prestada principalmente em regi?es urbanas densas. Neste trabalho ? realizada a predi??o de s?ries temporais em rede WCDMA - HSPA dos par?metros Rx Power, RSCP (Received Signal Code Power), Ec/Io (Energy per chip/Interference) e taxa de transmiss?o (throughput) na camada f?sica. A coleta dos valores dos par?metros foi realizada numa rede em pleno funcionamento atrav?s de um drive test na cidade de Natal ? RN, uma capital do nordeste brasileiro. Os modelos utilizados para predi??es das s?ries temporais foram os de Alisamento Exponencial Simples, Holt, Holt-Winters Aditivo e Holt-Winters Multiplicativo. O objetivo das predi??es das s?ries temporais ? verificar qual modelo ir? gerar as melhores predi??es dos par?metros da rede WCDMA - HSPA. / With the growing demand of data traffic in the networks of third generation (3G), the mobile operators have attempted to focus resources on infrastructure in places where it identifies a greater need. The channeling investments aim to maintain the quality of service especially in dense urban areas. WCDMA - HSPA parameters Rx Power, RSCP (Received Signal Code Power), Ec/Io (Energy per chip/Interference) and transmission rate (throughput) at the physical layer are analyzed. In this work the prediction of time series on HSPA network is performed. The collection of values of the parameters was performed on a fully operational network through a drive test in Natal - RN, a capital city of Brazil northeastern. The models used for prediction of time series were the Simple Exponential Smoothing, Holt, Holt Winters Additive and Holt Winters Multiplicative. The objective of the predictions of the series is to check which model will generate the best predictions of network parameters WCDMA - HSPA.

Submitted by Neusa Fagundes (neusa.fagundes@unioeste.br) on 2018-02-09T11:48:18Z No. of bitstreams: 2 Ketllin_Conceição2017.pdf: 1478973 bytes, checksum: a97631da6b15f46cfa48d39a4a2e9892 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-02-09T11:48:18Z (GMT). No. of bitstreams: 2 Ketllin_Conceição2017.pdf: 1478973 bytes, checksum: a97631da6b15f46cfa48d39a4a2e9892 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-06-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The unplanned development of large urban centers as well as the industrial one have hindered sustainable awareness regarding the correct water application. The unruly use of this resource has drawn the scientific community attention, thus, several scientific trials have been carried out in order to evaluate the use and quality of water. The use of indicators is one of the possibilities to evaluate water quality, which aims at analyzing physical-chemical and biological characteristics, and so allowing the evaluation of water body quality. In order to quickly evaluate the parameters involving water quality index (WQI), the process capability index was used. Thus, this trial aims at determining the water quality index as well as applying statistical quality control methodologies to evaluate the monitoring of water quality in rivers. Therefore, a database with physical-chemical and microbiological parameters from Passaúna and Piraquara rivers was applied to carry out this research development. Those rivers are in Araucária and Piraquara cities, respectively. The water quality index was determined by the time series, and subsequently data were submitted to statistical process control, with Shewhart individuals, EWMA and CUSUM, control charts as well as the development of the process quality index. Based on these data, a model of forecast was developed according to Holt-Winters Additive method. The WQI detected that the studied rivers remained under an averaged quality until the year of 2000, however, since that year, it was possible to observe a decreasing trend in water quality of the evaluated rivers. This trend was also identified by control charts. The graphs were also able to identify that waters of the rivers were not under statistical control, identifying some points that exceeded the used control limits. The process capacity index showed that the Piraquara River was classified with better quality of water when compared to the Passaúna River. The Holt-Winters prediction method showed that both rivers would continue with a decreasing trend in WQI and consequently in water quality. The applied statistical tools proved to be fast and efficient to evaluate water quality control. Finally, it is suggested that other researches should be developed using the technique of statistical process control for environmental evaluation. / O desenvolvimento desordenado dos grandes centros urbanos e o desenvolvimento industrial vêm dificultando a conscientização sobre o uso racional e sustentável da água. O uso indiscriminado desse recurso vem chamando atenção da comunidade científica e percebe-se uma infinidade de trabalhos científicos a fim de que se avaliem o uso e a qualidade da água. Uma das formas de se avaliar a qualidade da água é pela utilização de indicadores, que têm por finalidade analisar as características físico-químicas e biológicas e, assim, permitir a avaliação da qualidade das águas de um corpo hídrico. Utilizou-se o índice de capacidade do processo para se avaliar de forma rápida os parâmetros que envolvem o índice de qualidade da água (IQA). Desse modo, objetivou-se com esse trabalho determinar o índice de qualidade da água bem como aplicar metodologias de controle de qualidade estatístico para avaliar o monitoramento de qualidade da água em rios. Portanto, para se realizar o desenvolvimento da pesquisa, foi utilizado um banco de dados com parâmetros físico-químicos e microbiológicos dos rios Passaúna e Piraquara, pertencentes às cidades de Araucária e Piraquara, respectivamente. O índice de qualidade da água foi determinado com a série temporal e, posteriormente, esses dados foram submetidos ao controle estatístico do processo, com os gráficos de controle de Shewhart individual, MMEP e CUSUM, além do desenvolvimento do índice de qualidade do processo. A partir desses dados foi desenvolvido um modelo de previsão com o método de Holt-Winters Aditivo. O IQA detectou que os rios mantiveram-se em qualidade média até o ano 2000, entretanto, a partir desse ano foi possível visualizar uma tendência decrescente na qualidade das águas dos rios avaliados. Essa tendência também foi identificada pelos gráficos de controle. Os gráficos foram capazes de identificar que as águas dos rios não estavam em controle estatístico, identificando alguns pontos que excederam os limites de controle utilizados. O índice de capacidade do processo demonstrou que o rio Piraquara foi classificado com águas de melhor qualidade, quando comparado ao rio Passaúna. O método de previsão de Holt-Winters demonstrou que continuaria com uma tendência decrescente no IQA e, consequentemente, na qualidade da água, em ambos os rios avaliados. As ferramentas estatísticas utilizadas demonstraram ser rápidas e eficientes para a avaliação do controle de qualidade de águas. Por fim, sugere-se que sejam desenvolvidas mais pesquisas utilizando a técnica do controle estatístico do processo para avaliação do meio ambiente.

The purpose of this study is to determine. whether Charles Dickens's educational theories in England during the nineteenth century are conclusively juxtaposed to John Holt's educational theories in America during the twentieth century. Chapter One introduces the proposition and states the general nature of the discussion in -subsequent chapters. Chapter Two presents a history of economic conditions in nineteenth-century England and shows how its evolution influenced Dickens's educational theories. Chapter Three discusses the economic conditions in twentieth-century America, the moral crisis- and its affect on youth, and Holt's theories of how children fail and how they learn. Chapter Four synthesizes Dickens's and Holt's -theories and establishes that their philosophies and aims in the field of education are closely juxtaposed.

Dangerous Instincts is a collection of poems unified thematically by recurring and interstitial questions of the wilderness, the natural sciences - particularly astrophysics - the occult, and the mythic universe. These poems explore the mystical implications of the natural world and its meaning in the aesthetic consciousness, particularly in a highly secular century. Implied is the poet’s selfdiscovery and search for the divine. The collection emerges, not simply as interpretation, but a means of coming to terms with the fear of and compulsion to question the universe, and through those questions find illumination in the ordinariness of lived life and in the mystery and magic of complex phenomena. As a whole, the work is largely lyrical; occasionally it calls upon forms such as the villanelle and ekphrasis as deliberate formal poetic experiments. Sometimes the images are familiar recreations of creation myths and forest fires, and sometimes they range into as private and esoteric a realm as occult rituals, Scottish fairytale, and quantum entanglement. Dangerous Instincts is divided into five sections that explore the physical realm in terms of distances: from outward to inward, from heights to depths, and from beyond the speaker’s understanding to intrinsically self-reflexive poems written to amplify my notion that at the heart of poetry is myth.

[pt] Após o choque de racionamento de energia elétrica, decorrente do desequilíbrio entre oferta e demanda, os vários setores da sociedade brasileira constataram a real e iminente necessidade de diversificação das fontes de geração de energia elétrica e de seu uso racional. Busca-se hoje novas fontes, entre as quais a energia eólica, uma alternativa nova e promissora. A energia eólica está aumentando no mundo todo e o Brasil tem um enorme potencial devido a sua localização geográfica e o governo tem investido neste tipo de energia. O principal objetivo desta dissertação é estudar e desenvolver modelos de previsão de velocidade de vento, de curto prazo da velocidade do vento. Os métodos de amortecimento exponencial, em particular o método de Holt-Winters e suas variações, são apropriados para este contexto devido à sua alta adaptabilidade e robustez. Para aplicação da metodologia considerou-se o município de São João do Cariri (Estado de Paraíba), onde está localizada uma das estações de referência do projeto SONDA (Sistema Nacional de Dados Ambientais para o setor de energia). Será utilizado o método de Holt-Winters, que será comparado com os modelos: de persistência, neuro-fuzzy (ANFIS) e estatísticos. / [en] After the shock of electricity rationing, due to the imbalance between supply and demand, the various sectors of the Brazilian society found a real and imminent need to diversify sources of electricity generation and its rational use. New sources are searched today, including wind power, a promising new alternative. Wind energy has been increasing worldwide and Brazil has huge potential due to its geographical location and the government has invested in this type of energy. The main objective of this thesis is to study and develop forecasting models, of short-term wind speed. The methods of exponential smoothing, in particular the method Holt-Winters and its variations, are suitable in this context because of its high adaptability and robustness. The city of São João do Cariri (State of Paraíba), where it is located one of the reference stations of project SONDA (National Environmental Data for the energy sector) was chosen in order to apply the methodology. The method that will be used is Holt-Winters, who will be compared with the models: persistence, neuro-fuzzy (ANFIS) and statistics.

I denna rapport presenteras ett tillvägagångssätt för att hitta och datera brytpunkter i tidsserier. En brytpunkt definieras av det datum då det skett en stor nivåförändring i tidsserien. Det presenteras även en strategi för att skatta effekten av daterade brytpunkter. Genom att analysera tidsserier över AFA Försäkrings ärendeinflöde visar det sig att brytpunkter i tidsserien sammanfaller med exogena händelser som kan ha orsakat dessa brytpunkter, till exempel villkors- eller lagförändringar inom försäkringsbranschen. Rapporten visar att det genom ett metodiskt angreppssätt går att skatta effekten av en exogen händelse. Dessa skattade effekter kan användas vid framtida prognoser då en liknande förändring förväntas inträffa. Dessutom skapas prognoser över ärendeinflödet två år framåt med olika tidsseriemodeller.

[pt] O ONS (operador nacional do sistema elétrico brasileiro) vem utilizando o software ANNSTLF produzido pelo EPRI/EUA (Eletrical Power Research Institute) para realizar a previsão do consumo de carga horária. Entretanto, as estimativas fornecidas pelo programa estão fundamentadas na metodologia de uma rede neural que, de certo modo, impede ao usuário de extrair uma maior interpretação dos resultados que são fornecidos pela rede. Assim sendo, este trabalho pesquisou os métodos univariados convencionais: Holt-Winters e Box e Jenkins, considerando suas formulações aperfeiçoadas e adaptadas às características próprias do tipo de série em questão. Isto é, assumindo a existência de dois ciclos sazonais: um diário e outro semanal. A vantagem destas técnicas univariadas, em comparação ao ANNSTLF, é principalmente a interpretabilidade das informações obtidas. Dessa forma, esta pesquisa permite também avaliar melhor o desempenho do ANNSTLF. / [en] The ONS (National Operator of the Brazilian electrical system) has been using the software ANNSTLF produced by EPRI/USA (Eletrical Power Research Institute) to carry out the forecast of the hourly load consumption. However, the estimates supplied by the program are based on the methodology of a neural net that, in a way, does not allow the user to extract a better interpretation of the results produced by the net. Therefore, investigates the conventional univaried methods: Holt-Winters and Box & Jenkins, considering its formulations perfected and adapted to the characteristics of the series understudy. That is, its assumed the existence of two seasonal cicles: daily and weekly. The advantage of these univariate techniques, in comparison to the ANNSTLF, is mainly the ability to interpret the model estimates. Also, this research also allows a better evaluation the performance of the ANNSTLF.

Made available in DSpace on 2014-07-29T15:08:23Z (GMT). No. of bitstreams: 1 dissertacaoPriscila.pdf: 645879 bytes, checksum: 1150784f73524c6b5341fd319cc9d608 (MD5) Previous issue date: 2009-01-02 / n the planning of the energetic operation, analysis and forecasts of the flow are very important. A huge difficulty in the forecast of flow is the seasonality presence, due to drought and flood periods in the year. Many scientists, with different methodologies, have been concerned with finding a best model, compared with the utilized by Brazil s system - Markovian Model. The Makovian Model, or selfregressive with order 1, is a Box & Jenkins methodology, and requires data handling to treat non-stationarity, or the use of regular models, requiring a hardly theoretical formulation for the statistical procedures. Therefore, the statistical models, autoregressive model with seasonality and Holt-Winters model, of treatment of temporal series are presented and, carried out the flow s analysis and forecast for three study groups, in two different (historical) horizons. The performance of the models was compared and the results showed that the proposed models presents better adjust than the model adopted by Brazilian system / No planejamento da operação energética, a análise e previsão de vazões são muito importantes. Uma grande dificuldade na previsão de vazões é a presença da sazonalidade, devido aos períodos de seca e cheia no ano. Muitos estudiosos, com metodologias diversas, têm se preocupado em encontrar um modelo de melhor ajuste, em comparação ao utilizado pelo sistema brasileiro, ou seja, o modelo auto-regressivo de ordem 1, que consiste numa metodologia de Box & Jenkins e exige manuseio nos dados para tratar a não-estacionariedade. O presente trabalho analisa e compara os modelo utilizados pelo sistema brasileiro (PAR), com modelo matemático que considera a sazonalidade dos dados (SAR) e o método de Holt-Winters e, modelos amplamente estudados como PARMA e ANFIS. O desempenho dos modelos foi comparado e os resultados mostraram que em muitos estudos os modelos PAR/PARMA e ANFIS apresentam melhor ajuste , no geral, em relação aos demais

Predicting future sales can bring many advantages to retailers with regards to organizational performance. Using big data to make accurate forecasts can enable retailer to improve their operational performance and profitability substantially by reducing lost sales, inventory levels and labor costs. Previous research within the field of retail forecasting has mostly been dedicated to forecasting on lower time granularities such as weekly and monthly. However, despite the high practicality for retailers, forecasts on higher frequencies have not been properly covered by the current literature. This study aims to investigate how to forecast future sales using high-frequency data for a Swedish pharmacy retail chain. The forecasts are made on a daily and sub-daily time granularity using time series models SARIMA, Holt-Winter’s method and Facebook Prophet. The results show that Facebook Prophet was the most practical model and had the highest forecasting accuracy both on a daily and sub-daily frequency according to the error metrics MAPE, MAE and RMSE. / Att förutsäga framtida försäljning kan medföra många fördelar för detaljis-ter när det gäller organisationens prestanda. Att använda big data för att göra korrekta prognoser kan göra det möjligt för återförsäljare att förbättra sin lönsamhet avsevärt genom att minska förlorad försäljning, lagernivåer och arbetskostnader. Tidigare forskning inom området prognoser inom de-taljhandeln har mestadels ägnat sig åt prognoser på lägre tidsgranulariteter såsom veckovis och månadsvis. Trots att prognoser är mycket praktiska för detaljister så har prognoser på högre frekvenser inte täckts ordentligt av den aktuella litteraturen. Denna masteruppsats syftar till att undersöka hur man kan prognostisera framtida försäljning med hjälp av högfrekvent data för en svensk apotekskedja .Prognoserna görs på en daglig och sub-daglig tidsgranularitet medt idsseriemodellerna SARIMA, Holt-Winters metod och Facebook Prophet. Resultaten visar att Facebook Prophet var den mest praktiska tidsseriemodellen och hade den högsta träffsäkerheten både på en daglig och sub-daglig frekvens enligt felmåtten MAPE, MAE och RMSE.