Research Report: Recent submissions

Now showing items 1-20 of 130

    • INFERENCE PRINCIPLES FOR MULTIVARIATE SURVEILLANCE 

      Frisén, Marianne (2011-03-29)
      Multivariate surveillance is of interest in industrial production as it enables the monitoring of several components. Recently there has been an increased interest also in other areas such as detection of bioterrorism, ...

    • STATISTICAL RANK METHODS FOR ORDINAL CATEGORICAL DATA 

      Holm, Sture; Svensson, Elisabeth (University of Gothenburg, 1991-03-01)
      The aim of this paper is to present a new rank. method for analysing ordinal scale problems, and to give some of its basic properties. The method is suitable for the assessment of validity and reliability of health measurement ...

    • ASPECTS OF MODELLING NONLINEAR TIME SERIES 

      Teräsvirta, Timo; Tjøstheim, Dag; Granger, Clive W J (University of Gothenburg, 1992-01-01)
      It is common practice for economic theories to postulate non-linear relationships between economic variables, production functions being an example. If a theory suggests a specific functional form, econometricians can ...

    • Exact Semiparametric Inference About the Within-Subject Variability in 2 x 2 Crossover Trails. 

      Guilbaud, Olivier (University of Gothenburg, 1992-03-01)
      The comparison of primary interest in a 2 x 2 crossover trial typically concerns the effect of the treatments, say A and B, on the mean response level. This article deals with another important aspect, namely the within-subject ...

    • SEPARATION OF SYSTEMATIC AND RANDOM ERRORS IN ORDINAL RATING SCALES 

      Svensson, Elisabeth; Holk, Sture (University of Gothenburg, 1992-04-01)
      The aim of this paper is to introduce a new rank method which enables us to separate the inconsistency of repeated measurements into random and systematic differences and to quantify this lack of consistency in a few ...

    • COMPARISON BETWEEN TWO METHODS OF SURVEILLANCE: EXPONENTIALLY WEIGHTED MOVING AVERAGE VS CUSUM 

      Frisén, Marianne; Åkermo, Göran (University of Gothenburg, 1993-01-01)
      When control charts are used in practice it is necessary to know the characteristics of the charts in order to know which action is appropriate at an alarm. The probability of a false alarm, the probability of successful ...

    • EXACT PROPERTIES OF McNEMAR'S TEST IN SMALL SAMPLES 

      Jonsson, Robert (University of Gothenburg, 1993-02-01)
      The exact distribution of McNemar's test statistic is used to determine critical pOints for two-sided tests of equality of marginal proportions in the correlated 2x2 table. The result is a conservative unconditional test ...

    • RESAMPLING PROCEDURES IN LINEAR MODELS 

      Gellerstedt, Martin (University of Gothenburg, 1993-03-01)
      We will study here different resampling procedures for creating confidence sets in linear models. A special technique called abstract resampling makes it possible to use the true residuals and the true model for resampling. ...

    • Statistical surveillance of business cycles 

      Frisén, Marianne (University of Gothenburg, 1994-01-01)
      Methods for timely detection of turning-points in business cycles are discussed from a statistical point of view. The theory on optimal surveillance is used to characterize different approaches advocated in literature. ...

    • CHARACTERIZATION OF METHODS FOR SURVEILLANCE BY OPTIMALITY 

      Frisén, Marianne (University of Gothenburg, 1994-02-01)
      Different criteria of optimality are discussed. The shortcomings of some earlier criteria of optimality are demonstrated by their implications. The correspondences between some criteria of optimality and some methods are ...

    • VISUAL EVALUATIONS OF STATISTICAL SURVEILLANCE 

      Frisén, Marianne; Cassel, Claes (University of Gothenburg, 1994-03-01)
      A computer program which simultaneously gives visual information on important characteristics is presented. Surveillance, that is continual observation of a time series with the goal of timely detection of possible important ...

    • A COMPARISON OF TWO DESIGNS FOR ESTIMATING A SECOND ORDER SURFACE WITH A KNOWN MAXIMUM 

      Ekman, Claes (University of Gothenburg, 1994-04-01)
      Two level fractional factorial designs with a star are often used when working with lower polynomial models. In this paper an alternative design is discussed and compared with the fractional factorial design. We are working ...

    • COMPARING POWER AND MULTIPLE SIGNIFICANCE LEVEL FOR STEP UP AND STEP DOWN MULTIPLE TEST PROCEDURES FOR CORRELATED ESTIMATES 

      Palaszewski, Bo (University of Gothenburg, 1994-05-01)
      We consider hypothesis testing problems arising in e.g. the context of comparing k treatments with a control. The case of equi-correlated estimates is mainly discussed, although also unequal correlated estimates (e.g. ...

    • CONSTANT PREDICTIVE VALUE OF AN ALARM 

      Åkermo, Göran (University of Gothenburg, 1994-06-01)
      One main purpose of statistical surveillance is to detect a change in a process, often expressed as a shift from one level to another. When a sequence of decisions is made, measures, like the number of decisions that have ...

    • ON PERFORMANCE OF METHODS FOR STATISTICAL SURVEILLANCE 

      Åkermo, Göran (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 ...

    • SATURATED DESIGNS FOR SECOND ORDER MODELS 

      Ekman, Claes (University of Gothenburg, 1994-09-01)
      Construction of saturated designs for different types of second order models are discussed. Also a comparison between two types of saturated designs for the full second order model is presented.

    • A NOTE ON ROTATABILITY 

      Ekman, Claes (University of Gothenburg, 1994-10-01)
      The need of a measure of rotatability is discussed and exemplified through some examples. The examples also shows the difficulties with measuring rotatability. A graphical technique for exploring the variance function is ...

    • SURVEILLANCE OF RARE EVENTS. ON EVALUATION OF THE SETS METHOD 

      Arnkelsdóttir, Hrafnhildur (University of Gothenburg, 1995-01-01)
      Continual surveillance aiming to detect an increased frequency of some rare event is of interest in several different situations in quality control, medicine, economics and other fields. Examples are continual surveillance ...

    • DETECTION OF GRADUAL CHANGES. STATISTICAL METHODS IN POST MARKETING SURVEILLANCE 

      Sveréus, Alecka (University of Gothenburg, 1995-02-01)
      Surveillance can be viewed as continual observation in time where the goal is to detect a change in the underlying process as soon as possible after it has occurred. In many applications, such as post marketing surveillance, ...

    • ON SECOND ORDER SURFACES ESTIMATION AND ROTABlLITY 

      Ekman, Claes (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; ...