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A CUSUM PROCEDURE FOR DETECTION OF OUTBREAKS IN POISSON DISTRIBUTED MEDICAL HEALTH EVENTS
(University of Gothenburg, 2010-11-02)CUSUM procedures which are based on standardized statistics are often supposed to have expectation zero and being normally distributed. If these conditions are not satisfied it can have serious consequences on the determination ... -
A comparison of conditioned versus unconditioned forecasts of the V AR(l) process
(University of Gothenburg, 2003-05-01)The properties of a forecast usually depend upon whether the forecast is conditioned on the final period observation or not. In the case of unconditioned forecasts it is well known that the point predictions are unbiased. ... -
A COMPARISON OF TWO DESIGNS FOR ESTIMATING A SECOND ORDER SURFACE WITH A KNOWN MAXIMUM
(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 ... -
A monitoring system for detecting starts and declines of influenza epidemics
(2003-12-01)The aim is to detect an influenza outbreak as soon as possible. Data are weekly reports of number of patients showing influenza-like symptoms. At each additional observation we decide whether a change has occurred or ... -
A NOTE ON ROTATABILITY
(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 ... -
A stepwise regression procedure applied to an international production study - a multiple inference solution
(University of Gothenburg, 1997-04-01)The aim of this paper is to apply a certain procedure for stepwise regression analysis to a problem included in a study of integrated international production. The question, which factors are important for the transnational ... -
A TIPPETT-ADAPTIVE METHOD OF COMBINING INDEPENDENT STATISTICAL TESTS.
(University of Gothenburg, 1986-03-01)A new procedure is proposed in order to combine the information of P-values obtained from several independent tests in order to test an overall hypothesis. The test statistic of this new procedure is of the same type as ... -
ABSTRACT BOOTSTRAP CONFIDENCE INTERVALS IN LINEAR MODELS
(University of Gothenburg, 1990-01-01)A bootstrap method for generating confidence intervals in linear models is suggested. The method is motivated by an abstract nonobservable bootstrap sample of true residuals leading to an observable final result. This means ... -
ANALYS AV KATEGORISKA DATA - En metodstudie i anslutning till statsvetenskaplig forskning.
(University of Gothenburg, 1983-02-01)Inriktningen av denna rapport har praglats av forfattarens erfarenheter fran arbetet med urvalsplaner for delundersokningarna avseende medborgare, politiker och tjansteman inom forskningsprogrammet 1979-1981 for utvardering ... -
ASPECTS OF MODELLING NONLINEAR TIME SERIES
(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 ... -
Aspects on the controi of false alarms in statistical surveillance and the impact on the return of financial decision systems
(2004-02-01)Systems for on-line detection of regime shifts are important, e.g. for making timely financial transactions. For daily data, it means that we make a new decision each day, based on the data available, and when there is ... -
Aspects on tolerance limit estimation - some common approaches and flexible modeling
(University of Gothenburg, 2000-02-01)In a dose finding study the aim is to attain a safe and efficient drug therapy in a certain population. By a dose finding study we generally refer to a study where the dosage is successively adjusted after analyzing the ... -
Bayes prediction of binary outcomes based on correlated discrete predictors.
(University of Gothenburg, 2002-03-01)An approach based on Bayes theorem is proposed for predicting the binary outcomes X = 0, 1, given that a vector of predictors Z has taken the value z. It is assumed that Z can be decomposed into 9 independent vectors given ... -
Characterization of methods for surveillance by optimality
(University of Gothenburg, 1999-12-02)Different criteria of optimality are discussed. The shortcomings of some criteria of optimality are demonstrated by their implications. The correspondences between some criteria of optimality and some methods are examined. ... -
CHARACTERIZATION OF METHODS FOR SURVEILLANCE BY OPTIMALITY
(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 ... -
COMPARING POWER AND MULTIPLE SIGNIFICANCE LEVEL FOR STEP UP AND STEP DOWN MULTIPLE TEST PROCEDURES FOR CORRELATED ESTIMATES
(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. ... -
COMPARISON BETWEEN TWO METHODS OF SURVEILLANCE: EXPONENTIALLY WEIGHTED MOVING AVERAGE VS CUSUM
(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 ... -
Consequences of using the probability of a false alarm as the false alarm measure
(2007-11-26)In systems for on-line detection of regime shifts, a process is continually observed. Based on the data available an alarm is given when there is enough evidence of a change. There is a risk of a false alarm and here two ...