Very often the interesting variables are explained by several underlying variables and in statistical analyses it is common to study the relationship between variables and groups of variables. Because of this multivariate analysis is commonly used in both science and industry. There are two problem with both univariate and multivariate analyses. One is when the variables are correlated. The other is when the number variables of exceeds the number of observations which makes the matrices algebra used in the analysis impossible to execute.

Very often the interesting variables are explained by several underlying variables and in statistical analyses it is common to study the relationship between variables and groups of variables. Because of this multivariate analysis is commonly used in both science and industry. There are two problem with both univariate and multivariate analyses. One is when the variables are correlated. The other is when the number variables of exceeds the number of observations which makes the matrices algebra used in the analysis impossible to execute.

Very often the interesting variables are explained by several underlying variables and in statistical analyses it is common to study the relationship between variables and groups of variables. Because of this multivariate analysis is commonly used in both science and industry. There are two problem with both univariate and multivariate analyses. One is when the variables are correlated. The other is when the number variables of exceeds the number of observations which makes the matrices algebra used in the analysis impossible to execute.

A lot of mine waste rock and tailings arise from all mining processes and have to be stored in an appropriate way. Tailings are deposited in impoundments retained by tailings dams. The objective of tailings dams is to retain the slurry from the mining process and in that way prevent spill into the surroundings that might be harmful for the environment. Tailings dams are often constructed as staged embankments so that construction costs and demand of materials are spread more evenly over the period of deposition.The objective of this thesis has been to compile information about and evaluate events at Swedish tailings dams and also to develop a collective database for all Swedish mining companies for all tailings dams and all events that occur at tailings dams.Information about 60 events at Swedish tailings dams has been gathered and evaluated. The evaluation has been performed by comparison between and analysis of individual parameters and also by use of a multivariate statistical method called PLS.

This thesis examines a sample of Pitted Ware pottery from the Gotlandic site of Ajvide in regard to the spatial and temporal relationship of the shards. Ajvide Stone Age site have been extensively excavated over the past 25 years and the most recent analysis of pottery was carried out by Inger Österholm in 1987 and new analyses of the material are therefore greatly needed. Pottery from three sample areas was analysed in regard to their distribution, decoration, fragmentation, part of pot and quality of the goods. To analyse the material in a contextual way a Multivariate Statistical Analysis called correspondence analysis was used. Two areas denominated ?dark areas?, which Österholm defined previously, as possible ritual sites, and one reference area with mixed material were chosen for the analysis.

The value investing philosophy, which can be traced at least to the teaching of Graham and Dodd in the 1930?s, entails identifying and investing in potentially under valued stocks with a potential for extraordinary returns. The focus of this thesis is to identify patterns and characteristics in financial accounting data preceding creation of shareholder value. The authors of this thesis utilize a multivariate discriminant analysis in order to identify indicators of value creation and subsequent extraordinary returns in value stocks. A discriminant function is derived which successfully identifies which value stocks will eventually become growth stocks.

Vid analys av fluider med akustisk spektroskopi finns ett behov av att finna multivariata metoder för att utifrån akustiska spektra prediktera storheter såsom viskositet och densitet. Användning av artificiella neurala nätverk och bayesiska nätverk för detta syfte utreds genom teoretiska och praktiska undersökningar. Förbehandling och uppdelning av data samt en handfull linjära och olinjära multivariata analysmetoder beskrivs och implementeras. Prediktionsfelen för de olika metoderna jämförs och PLS (Partial Least Squares) framstår som den starkaste kandidaten för att prediktera de sökta storheterna..

The thick-shelled river mussel (Unio crassus) is a red listed species classified as Endangered (EN) and is also considered within the Habitats Directive. The distribution in Sweden is fragmented and it is mostly occurring in the south eastern parts. We investigated the presence of Unio crassus in a section of the stream Storån, Östergötland County, from Falerum to the inflow into Lake Åkervristen. The environmental parameters investigated were water depth, bottom substrate, shading, water velocity and the slope over the water surface. In this thesis I have focused mainly on water depth and shading, comparing sites with and without mussels.

The aim of this thesis is to examine the properties of the municipalities in Sweden that influence the choice of being a certified Fairtrade city. The independent variables which are used in the statistical analysis are municipal governance, local tax rate, whether there is an university and/or university college in the municipality, average income and higher education in the municipality. The variables are examined by logistic regression. Since there are no statistical data on ethical procurement, this exogenous variable isn?t included in the regression.

The aim of this thesis is to examine the properties of the municipalities in Sweden that influence the choice of being a certified Fairtrade city. The independent variables which are used in the statistical analysis are municipal governance, local tax rate, whether there is an university and/or university college in the municipality, average income and higher education in the municipality. The variables are examined by logistic regression. Since there are no statistical data on ethical procurement, this exogenous variable isn?t included in the regression.

A multivariate cross-sectional model is used in this thesis to proxy for expected earnings and to estimate return on equity for 214 companies over the period 2009-2013, using Swedish data. The model, which has never been tested on Swedish data before, is first confirmed to function as a forecasting model for expected return. Furthermore, the model is evaluated through a comparison with two univariate models based on the assumption that return on equity follows a mean reversion process. Forecast accuracy is calculated as the difference of estimated returns and actual returns. The results show that the univariate models' forecasts are superior to the multivariate model's..

The aim of this thesis is to find a statistical model that sort logs according to a predicted modulus of elasticity on the sawn boards. The input parameters for the model are X-ray variables from an X-ray scanner. For some of the log classes sawn at the sawmill it is desirable to have a narrow distribution of modulus of elasticity on the sawn boards. 250 pine logs from five different diameter classes were numbered and followed through the sawmill process. Log data were collected from X-ray and 3-D scanners in the log intake.

Hallsta paper mill uses large amounts of water during the pulp and paper making processes. The wastewater is treated in two separate activated sludge processes referred to as BIO 1 and BIO 2. The main aim is to reduce the organic substance content, measured as COD (Chemical Oxygen Demand) before the wastewater is released into the environment. Since the effluent produced is very rich in organic substances, the addition of nitrogen (N) and phosphorus (P) are necessary to give satisfactory treatment results. Problems with sludge bulking sometimes occur which lead to increased levels of suspended matter and nutrients in the effluent.

Testing and analysis of measurement data is a major part of the workday for development engineers within the section Fluid and Emission Treatment to assure the quality of products developed by Scania CV. The ineluctable variation and therefore uncertainty of results can be quantified and discussed with the use of statistical methods.The overall objective of this study is to examine how the competence of development engineers can be improved within the area of statistics. This has been done by relating the concept of competence with the use of statistical methods to analyse experimental data and by investigating which factors that influence the competence of the engineers. Observations of the daily operations, interviews and a focus group with development engineers and a workshop with management personnel, has been used as research methods in this study.The results show that the desired competence, from the perspective of the individual, consists of knowledge, motivation and support. It is important that none of these parts are neglected when the competence of engineers is to be strengthened.

There has been an increasing interest for ranking of Swedish health care and a lot of emphasis has been placed on the creation of indicators in order to rank hospital units. However, essays on to what extent the choice of statistical method affects the final result of the ranking of health care units have not been given the same attention. For this particular reason, the main objective of this essay has been to investigate whether the choice of statistical model has a significant impact or not on the final result, by using five different, more or less common, statistical approaches: bar charts (with and without confidence intervals), control charts, logistic regression, multi-level analysis using shrunken residuals. The analyzed material in the essay comprises 24119 patients that all have been prescribed some form of the lipid-reducing medicine statin. According to directives given by Region Skåne, doctors are encouraged to prescribe a particular type of statin medicine, namely Simvastatin, which has been proved to be equally effective, but significantly cheaper than other statin medicines.