Browsing Research Report by Title
Now showing items 62-81 of 130
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On assessing multivariate normality
(University of Gothenburg, 2001-01-01)Statistical analysis frequently relies on the assumption of normality. Though normality may often be relaxed in view of inferences of for example population expectations, it can be crucial in other aspects such as diagnostic ... -
On curve estimation under order restrictions
(2008-02-04)Robust regression is of interest in many problems where assumptions of a parametric function may be inadequate. In this thesis, we study regression problems where the assumptions concern only whether the curve is increasing ... -
On monitoring of environmental and other autoregressive processes
(University of Gothenburg, 1998-05-01)Statistical surveillance is used for monitoring a sequence of data arriving step by step. These techniques have been applied in many places in society and lately the interest and need for rational methods to be used on ... -
On monotonicity and early warnings with applications in economics
(University of Gothenburg, 1999-01-01)In this report a method for monitoring time series with cycles is presented. It is a nonparametric approach for detecting the turning point of the cycles. Time series of business indicators often exhibit cycles that can ... -
On multivariate control charts
(University of Gothenburg, 2011-02-10)Industrial production requires multivariate control charts to enable monitoring of several components. Recently there has been an increased interest also in other areas such as detection of bioterrorism, spatial surveillance ... -
ON PERFORMANCE OF METHODS FOR STATISTICAL SURVEILLANCE
(University of Gothenburg, 1994-07-01)Statistical surveillance is used to detect a change in a process. It might for example be a change of the level of a characteristic of an economic time series or a change of heart rate in intensive care. An alarm is triggered ... -
On seasonal filters and monotonicity
(University of Gothenburg, 2001-04-01)Seasonal adjustment is important in for example economic time series where the variation can be due to both seasonal and cyclical movements. In a situation where we want to detect a turning point of a cyclical process ... -
ON SECOND ORDER SURFACES ESTIMATION AND ROTABlLITY
(University of Gothenburg, 1995-03-01)The design of an experiment is an important component when collecting data to gain a deeper understanding of a problem. It is from the data collected that inferential statements concerning some phenomenon have to be made; ... -
ON SOME PREDICTION METHODS FOR CATEGORICAL DATA
(University of Gothenburg, 1991-01-01)Good prediction methods are important in many fields where qualitative variables are involved. The criterion of a good prediction method, used in this paper, is the average mean squared error. This criterion is used to ... -
On statistical surveillance of the performance of fund managers
(2009-02-17)The aim of this report is to describe if and how statistical surveillance methods for monitoring of the performance of fund managers has been used. Statistical surveillance is a methodology for on-line monitoring, in which ... -
On statistics and scientific thinking
(University of Gothenburg, 1999-08-01)Scientific thinking could in a wider scope be regarded as the process resulting in scientific knowledge. Such a definition is however at the same time to narrow and to wide since you could easily find projects ruled by the ... -
ON TESTS OF EQUIVALENCE
(University of Gothenburg, 1990-02-01)We will study here a general method for constructing equivalence tests for problems with onedimensional or multidimensional parameter. In the biometric field, the equivalence tests have been studied by many authors under ... -
ON THE PROBLEM OF OPTIMAL INFERENCE IN THE SIMPLE ERROR COMPONENT MODEL FOR PANEL DATA
(University of Gothenburg, 1991-02-01)For data consisting of cross sections of units observed over time, the Error Component Regression (ECR) model, with random intercept and constant slope, may sometimes be adequate. While most interest has been focused on ... -
Optimal surveillance Based on exponentially weighted moving averages
(University of Gothenburg, 2002-01-01)Statistical surveillance is used to detect an important change in a process as soon as possible after it has occurred, with control of false alarms. The EWMA, exponentially weighted moving average, method for surveillance ... -
Outlying observations and their influence on maximum pseudo-likelihood estimates of Gibbs point processes
(University of Gothenburg, 1996-05-01)Maximum pseudo-likelihood estimation method is an attractive method to estimate interaction parameters of Gibbs point processes. A drawback of the method is that it tends to overestimate interaction if there is strong ... -
PARAMETRIC AND NONPARAMETRIC TESTS FOR BXOEQUIVALENCE TRIALS
(University of Gothenburg, 1986-02-01)In pharmacology, comparison of bioavailability is an important problem. A new formulation of a drug is compared with a standard formulation in human subjects. When the extent of absorption is studied the areas under the ... -
Prediction of work resumption among men and women with lower back- and neck pain in a Swedish population
(University of Gothenburg, 2002-04-01)An approach based on Bayes theorem is used to predict the binary outcome of work resumption X, where X = 1 if no work resumption and X = 0 otherwise, given a vector of discrete predictors Z for men and women with lower ... -
Prediction of work resumption in theory and practice
(University of Gothenburg, 2002-05-01)In Sweden, the number oflong-term sick-listed has increased by about 30% per year during the period 1997-2001, and the cost for health insurance is 108 billion SEK in the state budget (2002). Thus, the prediction of work ... -
Predictions by early indicators of the time and height of yearly influenza outbreaks in Sweden
(2007-12-13)Aims: Methods for prediction of the peak of the influenza from early observations are suggested. These predictions can be used for planning purposes. Methods: In this study, new robust methods are described and applied ... -
Preliminary testing in a class of simple non-linear mixed models to improve estimation accuracy
(2003-09-02)In applied research hypothetical information about the parameters in a stochastic model sometimes can be generated from theory or previous studies. Replacing unknown parameters by constants might increase the estimation ...