Tore Schweder

• Lee Hsiang Liow, Hans Julius Skaug, Torbjørn Ergon and Tore Schweder "Global occurrence trajectories of microfossils: environmental volatility and the rise and fall of individual species" Paleobiology 36; 2010: 224-252
• Tore Schweder, Dinara Sadykova, David Rugh and William Koski "Population Estimates From Aerial Photographic Surveys of Naturally and Variably Marked Bowhead Whales" Journal of Agricultural Biological and Environmental Statistics 2010 15: 1-19
• Per Erik Jorde, Tore Schweder, JW Bickham, GH Givens, R. Suydam, D. Hunter and Nils Christian Stenseth, "Detecting genetic structure in migrating bowhead whales off the coast of Barrow, Alaska," Molecular Ecology, 2007: 1993-2004
• Tore Schweder and Rasmus Plenge Waagepetersen, "Likelihood-based inference for clustered line transect data," Journal of Agricultural, Biological, and Environmental Statistics, 2006, 11:264-279
• Hans J. Skaug, Nils Øien, Tore Schweder and Gjermund Bøthun, "Abundance of minke whales (Balaenoptera acutorostrata) in the Northeast Atlantic: variability in time and space," Can. J. Fish. Aquat. Sci. 61, 2004, 870-886
• Tore Schweder and Nils Lid Hjort, "Frequentist analogues of priors and posteriors," In B.P. Stigum, Econometrics and the philosophy of economics, Princeton University Press, 2003, 285-317.
• Tore Schweder,"Abundance estimation from photo-identification data: confidence distributions and reduced likelihood for bowhead whales off Alaska," Biometrics 59, 2003, 976-985
• Tore Schweder and Nils Lid Hjort, "Confidence and likelihood," Scandinavian Journal of Statistics 29, 2002, 309-332
• Olaf Gjerløw Aasland, Øvind Ekeberg and Tore Schweder, "Suicide rates from 1960 to 1989 in Norwegian physicians compared with other educational groups," Social Science and Medicine 52, 2001, 259-265
• Tore Schweder and Emil Spjøtvoll, "P-value plots to evaluate many tests simultaneously," Biometrika, 1982, 69: 493-502
• Tore Schweder, "Composable Markov Processes," Journal of Applied Probability, 1970, 7: 400-10

• Namek, Sara; Schweder, Tore & Lie, Mons (2021). Pasienter nyretransplantert ved Ullevål sykehus 1963–83. Tidsskrift for Den norske legeforening. ISSN 0029-2001. 141(18). doi: 10.4045/tidsskr.20.0579. Full text in Research Archive
• Cunen, Celine; Hjort, Nils Lid & Schweder, Tore (2020). Confidence in confidence distributions! Proceedings of the Royal Society. Mathematical, Physical and Engineering Sciences. ISSN 1364-5021. doi: 10.1098/rspa.2019.0781. Full text in Research Archive
• Schweder, Tore (2017). Confidence is epistemic probability for empirical science. Journal of Statistical Planning and Inference. ISSN 0378-3758. 195, p. 116–125. doi: 10.1016/j.jspi.2017.09.016. Full text in Research Archive
• De Blasi, Pierpaolo & Schweder, Tore (2017). Confidence distributions from likelihoods by median bias correction. Journal of Statistical Planning and Inference. ISSN 0378-3758. 195, p. 35–46. doi: 10.1016/j.jspi.2017.09.010. Full text in Research Archive
• Diekert, Florian Klaus & Schweder, Tore (2017). Disentangling Effects of Policy Reform and Environmental Changes in the Norwegian Coastal Fishery for Cod. Land Economics. ISSN 0023-7639. 93(4), p. 689–709. doi: 10.3368/le.93.4.689. Full text in Research Archive
• Hjort, Nils Lid & Schweder, Tore (2017). Confidence distributions and related themes. Journal of Statistical Planning and Inference. ISSN 0378-3758. 195, p. 1–13. doi: 10.1016/j.jspi.2017.09.017.
• De Blasio, Fabio V; Liow, Lee Hsiang; Schweder, Tore & De Blasio, Birgitte Freiesleben (2015). A model for global diversity in response to temperature change over geological time scales, with reference to planktic organisms. Journal of Theoretical Biology. ISSN 0022-5193. 365, p. 445–456. doi: 10.1016/j.jtbi.2014.10.031.
• Koyano, Hitoshi; Serbezov, Dimitar; Kishino, Hirohisa & Schweder, Tore (2013). Fractional parentage analysis and a scale-free reproductive network of brown trout. Journal of Theoretical Biology. ISSN 0022-5193. 336, p. 18–35. doi: 10.1016/j.jtbi.2013.06.038. Show summary

  In this study, we developed a method of fractional parentage analysis using microsatellite markers. We propose a method for calculating parentage probability, which considers missing data and genotyping errors due to null alleles and other causes, by regarding observed alleles as realizations of random variables which take values in the set of alleles at the locus and developing a method for simultaneously estimating the true and null allele frequencies of all alleles at each locus. We then applied our proposed method to a large sample collected from a wild population of brown trout (Salmo trutta). On analyzing the data using our method, we found that the reproductive success of brown trout obeyed a power law, indicating that when the parent-offspring relationship is regarded as a link, the reproductive system of brown trout is a scale-free network. Characteristics of the reproductive network of brown trout include individuals with large bodies as hubs in the network and different power exponents of degree distributions between males and females.

• Reitan, Trond; Schweder, Tore & Henderiks, Jorijntje (2012). Phenotypic evolution studied by layered stochastic differential equations. Annals of Applied Statistics. ISSN 1932-6157. 6, p. 1531–1551. doi: 10.1214/12-AOAS559. Full text in Research Archive
• Schweder, Tore & Preisler, Haiganoush (2012). Introductory comments to some applied papers by David R. Brillinger. In Guttorp, Peter & Brillinger, David R. (Ed.), Selected works of David Brillinger. Springer Science+Business Media B.V.. ISSN 9781461413431. p. 325–333.
• Schweder, Tore & Sadykova, Dinara (2012). Information dynamics and optimal sampling in capture-recapture. Biometrika. ISSN 0006-3444. 99(2), p. 488–493. doi: 10.1093/biomet/ass001. Show summary

  The build up of information in a continued capture-recapture experiment of simple random sampling of an open population is studied by predicting the conditional approximate Fisher information for abundance in data from one survey given the previous data. By neglecting the stochasticity in survival, a simple approximate likelihood is obtained. Optimal temporal allocation of a given total effort is found by numerical optimization for various objective functions based on the approximate Fisher information. For aerial photographic surveys of bowhead whales, the performance of estimates of abundance and of demographic parameters is compared between constant yearly survey effort and nominally optimal sampling by simulating a realistic model over 50 years.

• Kraugerud, Marianne; Aleksandersen, Mona; Nyengaard, JR; Østby, Gunn Charlotte; Gutleb, Arno & Dahl, Ellen [Show all 11 contributors for this article] (2012). In utero and lactational exposure to PCB 118 and PCB 153 alter ovarian follicular dynamics and GnRH-induced luteinizing hormone secretion in female lambs. Environmental Toxicology. ISSN 1520-4081. 27(11), p. 623–634. doi: 10.1002/tox.20679.
• Sadykova, Dinara; Skurdal, Jostein; Hessen, Dag Olav & Schweder, Tore (2011). Saving the largest makes a difference: exploring effects of harvest regulations by model simulations for noble crayfish, Astacus astacus. Fisheries Management and Ecology. ISSN 0969-997X. 18(4), p. 307–313. doi: 10.1111/j.1365-2400.2011.00784.x.
• Schweder, Tore; Sadykova, Dinara; Rugh, David & Koski, William (2010). Population Estimates From Aerial Photographic Surveys of Naturally and Variably Marked Bowhead Whales. Journal of Agricultural Biological and Environmental Statistics. ISSN 1085-7117. 15(1), p. 1–19. doi: 10.1007/s13253-009-0002-1. Show summary

  Abundance, mortality and population growth of bowhead whales are estimated from captures of 4894 putatively different individuals obtained from ten years of systematic photographic surveys conducted during the spring migration when most of the Bering-Chukchi-Beaufort population of bowheads migrates past Point Barrow, Alaska. A stringent matching protocol designed to prevent false positive matches of the naturally but variably marked individuals led to 42 resightings between years. The flip side of this stringency is a presence false negative, i.e. some true recaptures are not recognized as such The problem of false negatives is addressed by modeling the capture process and the matching process. The captures of an individual are assumed to follow a Poisson process with intensity depending stochastically on the individual whale and on the year. The probability of successfully matching a capture to a previous capture is estimated by logistic regression on the degree of marking and image quality. Individuals are recruited by the Pella-Tomlinson population model, assuming their mortality rate is constant. An approximate likelihood is maximized. Bias, which is mainly due to false negative matches, is corrected using bootstrapping, and confidence curves in agreement with previous results are obtained for key parameters.

• Liow, Lee Hsiang; Skaug, Hans Julius; Ergon, Torbjørn H. & Schweder, Tore (2010). Global occurrence trajectories of microfossils: environmental volatility and the rise and fall of individual species. Paleobiology. ISSN 0094-8373. 36(2), p. 224–252. doi: 10.1666/08080.1.
• Sadykova, Dinara & Schweder, Tore (2009). Migration ranks for bowhead whales (Balaena mysticetus) at Barrow in spring. Journal of Cetacean Research and Management. ISSN 1561-0713. 11(1), p. 17–22.
• Aldrin, Magne; Huseby, Ragnar Bang & Schweder, Tore (2008). A note on tuning the Catch Limit Algorithm for commercial baleen whaling. Journal of Cetacean Research and Management. ISSN 1561-0713. 10(3), p. 191–194. Show summary

  The Catch Limit Algorithm for commercial baleen whaling developed by the International Whaling Commission converges slowly to a steady depletion (proportion of carrying capacity), and consequently 300 years of management is proposed as horizon for tuning and computer simulation. Long-term depletion is rather insensitive to the parameter currently used for tuning, and an alternative control parameter is suggested for this purpose.

• Schweder, Tore (2007). Confidence nets for curves. In Nair, Vijay (Eds.), Advances in statistical modeling and inference. Essays in honor of Kjell A. Doksum. World Scientific. ISSN 981-270-369-1.
• Jorde, Per Erik; Schweder, Tore; Bickham, JW; Givens, GH; Suydam, R & Hunter, D [Show all 7 contributors for this article] (2007). Detecting genetic structure in migrating bowhead whales off the coast of Barrow, Alaska. Molecular Ecology. ISSN 0962-1083. 16, p. 1993–2004. doi: 10.1111/j.1365-294X.2007.03268.x.
• Schweder, Tore (2006). The Scenario Barents Sea study: a case of minimal realistic modelling to compare management strategies for marine ecosystems. In Boyd, Ian; Wanless, Sarah & Camphuysen, C.J. (Ed.), Top Predators in Marine Ecosystems. Their Role in Monitoring and Management. Cambridge University Press. ISSN 978-0-521-84773-5. p. 310–323.
• Waagepetersen, Rasmus & Schweder, Tore (2006). Likelihood-Based Inference for Clustered Line Transect Data. Journal of Agricultural Biological and Environmental Statistics. ISSN 1085-7117. 11, p. 264– 279 . Show summary

  The uncertainty in estimation of spatial animal density from line transect surveys depends on the degree of spatial clustering in the animal population. To quantify the clustering we model line transect data as independent thinnings of spatial shot-noise Cox processes. Likelihood-based inference is implemented using Markov chain Monte Carlo (MCMC) methods to obtain efficient estimates of spatial clustering parameters. Uncertainty is addressed using parametric bootstrap or by consideration of posterior distributions in a Bayesian setting. Maximum likelihood estimation and Bayesian inference are compared in an example concerning minke whales in the northeast Atlantic.

• Skaug, Hans Julius; Øien, Nils; Schweder, Tore & Bøthun, G (2004). Abundance of minke whales (Balaenoptera acutorostata) in the Northeast Atlantic: variability in time and space. Canadian Journal of Fisheries and Aquatic Sciences. ISSN 0706-652X. 61, p. 870–886.
• Skaug, Hans Julius; Øien, Nils; Schweder, Tore & Bøthun, Gjermund (2004). Abundance of minke whales (Balaenoptera acutorostrata) in the Northeastern Atlantic. Canadian Journal of Fisheries and Aquatic Sciences. ISSN 0706-652X. 61, p. 870–886.
• Schweder, Tore & Hjort, Nils Lid (2003). Frequentist analogues of priors and posteriors. In Stigum, Bernt Petter (Eds.), Econometrics and the Philosophy of Economics. Theory-Data Confrontations in Economics. Princeton University Press. ISSN 0-691-11300-9. p. 285–317.
• Aldrin, Magne; Holden, Marit & Schweder, Tore (2003). Comment on Cowling's "Spatial Methods for Line Transect Surveys". Biometrics. ISSN 0006-341X. 59, p. 186–188. Show summary

  We consider the problem of estimating the parameters of a two-dimensional Neyman-Scott process, from data collected through a line transect survey. Cowling (1998) suggested an estimation method based on a one-dimensional K-function along the transect line. However, her expression for the theoretical K-function is wrong. In this paper, we correct her K-function.

• Schweder, Tore (2003). Integrative fish stock assessment by frequentist methods: confidence distributions and likelihoods for bowhead whales. Scientia Marina. ISSN 0214-8358. 67, p. 89–97.
• Schweder, Tore (2003). Abundance estimation from photo-identification data: confidence distributions and reduced likelihood for bowhead whales off Alaska. Biometrics. ISSN 0006-341X. 59, p. 976–985.
• Schweder, Tore (2003). Discussion of Kardaun, O.J.W.F, Salomé, D., Schaafsma, W., Steerneman, A.G.M., Willems, J.C. and Cox, D.R. Reflections on Fourteen Cryptic Issues Concerning the Nature of Statistical Inference. International Statistical Review. ISSN 0306-7734. 71, p. 303–307.
• Schweder, Tore (2003). Abundance estimation from multiple photo surveys: Confidence distributions and reduced likelihoods for bowhead whales off Alaska. Biometrics. ISSN 0006-341X. 59, p. 974–983.
• Schweder, Tore (2002). Large structured models in applied science; challenges for statistics. Scandinavian Journal of Statistics. ISSN 0303-6898. Vol. 29, p. 189–191.
• Schweder, Tore & Hjort, Nils Lid (2002). Confidence and likehood. Scandinavian Journal of Statistics. ISSN 0303-6898. Vol. 29, p. 309–332.
• Schweder, Tore & Hjort, Nils Lid (2002). Confidence and likelihood. Scandinavian Journal of Statistics. ISSN 0303-6898. 29(2), p. 309–332. Show summary

  Confidence intervals for a single parameter are spanned by quantiles of a confidence distribution, and one-sided p-values are cumulative confidences. Confidence distributions are thus a unifying format for representing frequentist inference for a single parameter. The confidence distribution, which depends on data, is exact (unbiased) when its cumulative distribution function evaluated at the true parameter is uniformly distributed over the unit interval. A new version of the Neyman--Pearson lemma is given, showing that the confidence distribution based on the natural statistic in exponential models with continuous data is less dispersed than all other confidence distributions, regardless of how dispersion is measured. Approximations are necessary for discrete data, and also in many models with nuisance parameters. Approximate pivots might then be useful. A pivot based on a scalar statistic determines a likelihood in the parameter of interest along with a confidence distribution. This proper likelihood is reduced of all nuisance parameters, and is appropriate for meta-analysis and updating of information. The reduced likelihood is generally different from the confidence density. Confidence distributions and reduced likelihoods are rooted in Fisher-Neyman statistics. This frequentist methodology has many of the Bayesian attractions, and the two approaches are briefly compared. Concepts, methods and techniques of this brand of Fisher-Neyman statistics are presented. Asymptotics and bootstrapping are used to find pivots and their distributions, and hence reduced likelihoods and confidence distributions. A simple form of inverting bootstrap distributions to approximate pivots of the abc type is proposed. Our material is illustrated in a number of examples and in an application to multiple capture data for bowhead whales.

• Schweder, Tore (2002). Large Structured Models in Applied Sciences; Challenges for Statistics. Scandinavian Journal of Statistics. ISSN 0303-6898. 29(2), p. 189–191.
• Høst, Gudmund; Berg, Erlend; Schweder, Tore & Tjelmeland, Sigurd (2002). A Gamma/Direchlet model for estimating uncertainty in age-specific abundance of Norwegian spring-spawning herring. ICES Journal of Marine Science. ISSN 1054-3139. 59, p. 737–748. doi: 10.1006/jmsc.2001.1176. Show summary

  An approach to estimating the statistical uncertainty in age-specific abundance of Norwegian spring-spawning herring is presented. The method is applied to data from a survey on the overwintering stock in the Vestfjord system in northern Norway in December 1996. It is based on building separate statistical models for acoustic and biological data. The acoustic data are modelled as a gamma-transformed spatial random field and fitted to echo readings from the survey. The biological data are fitted to a two-stage model using multinomial sampling from Dirichlet-distributed age proportions. Uncertainty in the abundance by age distribution is obtained by bootstrapping. Previous assessments have a priori taken the abundance by age from a skewed distribution, such as gamma or log-normal families. In contrast, this analysis results in an estimated abundance by age that seems symmetric and does not display heavy tails.

• Schweder, Tore (2001). Skepsisens plass i biologien - om falske funn og fordreid usikkerhet. Biolog. ISSN 0801-0722. 3.
• Aasland, Olaf Gjerløw; Ekeberg, Øivind & Schweder, Tore (2001). Suicide rates from 1960 to 1989 in Norwegian physicians compared with other occupational groups. Social Science and Medicine. ISSN 0277-9536. 52, p. 259–265. Show summary

  The aim of the present study is to compare suicide rates between 1960 and 1989 for Norwegian physicians with corresponding rates for other Norwegians with and without university education, by age, gender, and five-year period, based on death certificates for all Norwegians who died in the period 1960-1989. There were 82 registered physician suicides, of which 9 were female, 265 suicides by persons with other university education, and 11,165 by persons with no university education. Suicide rate is measured in number of deaths per 100,000 person years. Crude suicide rates were 47.7 (95% CI 37.7-60.4) for male physicians, 20.1 (17.7-22.9) for other male university graduates, and 22.7 (22.2-23.2) for men with no university education. The corresponding figures for females were 32.3 (15.8-63.7), 13.0 (8.4-19.8) and 7.7 (7.5-8.0). Both for males and females, suicide rates, controlled for age and period, were significantly higher for physicians than for persons with other or no university education. Poisson modelling showed that the risk of suicide for male physicians has the same age pattern as for other males with higher education. In 1985-89 the suicide rate for male physicians increased nearly linearly from about 35 at the age 35-40 to about 100 at the age 75-79, which was almost three times higher than for the other male university graduates. For the age group 50-54 the estimated rate increases from about 50 in 1960-64 to about 90 in 1985-89. For the female physicians, the low number of cases prevents reliable estimation of trends. For male physicians, the trend from 1960 to 1989 is increasing. The estimated risk for a single physician to commit suicide was almost 5 times that of a married or co-habitant colleague. For 52% of the male and 85% of the female physicians the suicide method was poisoning. This is about twice the rates in the general population.

• Schweder, Tore (2001). Protecting whales by distorting uncertainty: non-precautionary mismanagement? Fisheries Research. ISSN 0165-7836. 52(3), p. 217–225. Show summary

  Precautionary management is based on science, and is incompatible with large fluctuations in the management regime. Whaling is managed by the International Whaling Commission, and has seen large fluctuations. It is argued that both the period of intense Antarctic whaling and the current period of protectionism have been unduly prolonged by scientists expanding out of proportion the uncertainty surrounding management issues. In the 1950s, uncertainty concerning fin whale stock status and trend was consistently distorted from one quarter, and in the 1990s a minority in the Scientific Committee blocked consensus over the Revised Management Procedure that had been successfully developed by the Committee. In both cases, the political consequence of expanded uncertainty in the science was lack of action, resulting in a continuation of ¿business as usual¿. Extending a period of heavy exploitation longer than the resource can sustain is mismanagement. Extending a period of extreme protectionism when the resource is known to scientists to sustain valuable exploitation is also mismanagement, even from a conservationist point of view. This might, in fact, erode the role of science in management and thus prepare the ground for subsequent over-exploitation. Distorting uncertainty by injecting controversy or otherwise expanding uncertainty has contributed to excessive fluctuations in management regimes and consequently in stock abundance. Detrimental fluctuations might continue, since science is side tracked and management now is based on sentiments that might fade.

• Aasland, Olaf Gjerløw; Ekeberg, Øivind & Schweder, Tore (2001). Suicide rates from 1960 to 1989 in Norwegian physicians compared with other educational groups. Social Science and Medicine. ISSN 0277-9536. 52(2), p. 259–265. Show summary

  There were 82 registered physician suicides, of which 9 were female, 265 suicides by persons with other university education, and 11,165 by persons with no university education. Suicide rate is measured in number of deaths per 100,000 person years. Crude suicide rates were 47.7 (95% CI 37.7-60.4) for male physicians, 20.1 (17.7-22.9) for other male university graduates, and 22.7 (22.2-23.2) for men with no university education. The corresponding figures for females were 32.3 (15.8-63.7), 13.0 (8.4-19.8) and 7.7 (7.5-8.0). Both for males and females, suicide rates, controlled for age and period, were significantly higher for physicians than for persons with other or no university education. Poisson modelling showed that the risk of suicide for male physicians has the same age pattern as for other males with higher education. In 1985-89 the suicide rate for male physicians increased nearly linearly from about 35 at the age 35-40 to about 100 at the age 75-79, which was almost three times higher than for the other male university graduates. For the age group 50-54 the estimated rate increases from about 50 in 1960-64 to about 90 in 1985-89. For the female physicians, the low number of cases prevents reliable estimation of trends. For male physicians, the trend from 1960 to 1989 is increasing. The estimated risk for a single physician to commit suicide was almost 5 times that of a married or co-habitant colleague. For 52% of the male and 85% of the female physicians the suicide method was poisoning. This is about twice the rates in the general population.

• Schweder, Tore (2000). Distortion of Uncertainty in Science: Antarctic Fin whales in the 1950s. Journal of international wildlife law and policy. ISSN 1388-0292. 3(1), p. 73–92. Show summary

  In the 1950s, the majority of scientists in the International Whaling Commission (IWC) argued that the fin whale was overexploited in the Southern Hemisphere. However, several other scientists throughout the period persistently objected to this view. The scientific controversy attendant to this issue engendered great uncertainty. This uncertainty contributed towards extending the period of excessive whaling, and nearly destroyed the IWC. This papers reviews the fin whale debate in detail, puts the debate in a political perspective, and argues that the intentional injection of controversy for non-scientific reasons in decision-making forums, which the author terms "distortion of uncertainty", constitutes an act of scientific miconduct.

• Schweder, Tore; Hagen, Gro Synøve & Hatlebakk, Einar (2000). Direct and indirect effects of minke whale abundance on cod and herring fisheries: A scenario experiment for the Greater Barents Sea. NAMMCO scientific publications. ISSN 1560-2206. 2, p. 120–133. Show summary

  To study the pattern of interaction between minke whale (Balaenoptera acutorostrata) abundance and the main fisheries in the Greater Barents Sea, a simulation experiment was carried out. The population model involves 4 species interconnected in a food web: cod (Gadus morhua), capelin (Mallotus villosus), herring (Clupea harengus) and minke whales. Minke whales are preying on cod, capelin and herring; cod are preying on (young) cod, capelin and herring; herring in the Barents Sea are preying on capelin; while capelin is a bottom prey in the model. The consumption function for minke whales is estimated from stomach content data and prey abundance data. The model is dynamic. Minke whale abundances are kept on fixed levels, while recruitment in fish is stochastic. For cod catches, both the direct effect of whales consuming cod, and the indirect effect due to whales competing with cod for food and otherwise altering the ecosystem, are linear and of equal importance. The net effect on the herring fishery is of the same magnitude as the net effect on the cod fishery, with each extra whale reducing the catches of both species by some 5 tonnes.

• Schweder, Tore (1999). Line transecting with difficulties; lessons from surveying minke whales. In Garner, G.W.; Amstrup, S.C.; Laake, J.L.; Manly, B.F.J.; McDonald, L.L. & Robertson, D.G. (Ed.), Marine Mammal Survey and Assessment Methods. A.A.Balkema. ISSN 90-5809-043-4. p. 149–166.
• Skaug, Hans Julius & Schweder, Tore (1999). Hazard models for line transect surveys with independent observers. Biometrics. ISSN 0006-341X. 55, p. 29–36. Show summary

  The likelihood function for data from independent observer line transect surveys is derived, and a hazard model is proposed for the situation where animals are available for detection only at discrete time points. Under the assumption that the time points of availability follow a Poisson point process, we obtain an analytical expression for the detection function. We discuss different criteria for choosing the hazard function and consider in particular two different parametric families of hazard functions. Discrete and continuous hazard models are compared and the robustness of the discrete model is investigated. Finally, the methodology is applied to data from a survey for minke whales in the northeastern Atlantic.

• Schweder, Tore; Skaug, Hans J.; Langaas, Mette & Dimakos, Xeni Kristine (1999). Simulated likelihood methods for complex double-platform line transect surveys. Biometrics. ISSN 0006-341X. 55, p. 678–687. Show summary

  The conventional line transect approach of estimating effective search width from the perpendicular distance distribution is inappropriate in certain types of surveys, e.g., when an unknown fraction of the animals on the track line is detected, the animals can be observed only at discrete points in time, there are errors in positional measurements, and covariate heterogeneity exists in detectability. For such situations a hazard probability framework for independent observer surveys is developed. The likelihood of the data, including observed positions of both initial and subsequent observations of animals, is established under the assumption of no measurement errors. To account for measurement errors and possibly other complexities, this likelihood is modified by a function estimated from extensive simulations. This general method of simulated likelihood is explained and the methodology applied to data from a double-platform survey of minke whales in the northeastern Atlantic in 1995.

• Schweder, Tore & Hagen, Gro Synøve (1999). A note on the cost of instability in whale management. Journal of Cetacean Reserch and Management. 1(2), p. 137–140. Show summary

  The history of whaling is characterized by considerable variation in management "philosophy". For example, an early period of overexploitation led eventually to the present period of protectionism, and might be followed by a period of excessive catches. Is such instability in long-term management costly? The risk of depletion is clearly increased with increasing instability. If the net production function governing the whale dynamics essentially is convex, it is demonstrated that long-term catches are necessarily smaller the greater the management instability. A simulation experiment is carried out to quantify the loss in whale catches due to "stop-go" instability in whale management. To examine possible costs in terms of fisheries for cod and herring, a multi-species simulation model is used, with minke whales managed by a stochastic stop-go procedure and with cod, herring and capelin managed by VPA-type procedures. In the simulations, whale catches are reduced by increased instability in whale management while long-term catches of cod and herring are unaffected, provided mean whale abundance is kept fixed.

View all works in Cristin

• Schweder, Tore & Hjort, Nils Lid (2016). Confidence, Likelihood, Probability. Statistical Inference with Confidence Distributions. Cambridge University Press. ISBN 9780521861601. 511 p.

View all works in Cristin

• Schweder, Tore (2015). Confidence is epistemic probability.
• Schweder, Tore & Hjort, Nils Lid (2014). Optimal and approximate likelihood.
• Schweder, Tore (2013). Integrating confidence intervals, likelihoods and condence distrubutions.
• Henderiks, Jorijntje; Gerecht, Andrea; Hannisdal, Bjarte; Liow, Lee Hsiang; Reitan, Tore & Schweder, Tore [Show all 7 contributors for this article] (2013). PhytoSCALE project: calibrating phytoplankton cell size as a proxy for climatic adaptation.
• Schweder, Tore & Hjort, Nils Lid (2013). Confidence Distribution, the Frequentist Distribution Estimator of a Parameter: A Review Discussions. International Statistical Review. ISSN 0306-7734. 81(1), p. 56–68. doi: 10.1111/insr.12004.
• Schweder, Tore (2012). Confidence distributions and confidence likelihood: distributional inference without priors.
• Hjort, Nils Lid & Schweder, Tore (2012). Structure and Uncertainty: Confidence and Likelihood.
• Schweder, Tore (2012). Causal sufficiency and Markov Completeness.
• Schweder, Tore (2012). Confidence distributions and confidence likelihood: distributional inference without priors.
• Reitan, Trond; Schweder, Tore & Henderiks, Jorijntje (2010). Modelling Phenotypic Evolution by Stochastic Differential Equations. Show summary

  In this presentation, we described how to use layered linear stochastic differential equations to model evolutionary processes. This model family was used in order to analyse microfossil data spanning several tens of millions of years.

• Henderiks, Jorijntje; Hannisdal, Bjarte; Rickaby, Rosalind E. M.; Liow, Lee Hsiang; Reitan, Trond & Schweder, Tore (2010). Phytoplankton size: climatic adaptation and long-term evolution.
• Schweder, Tore & Sadykova, Dinara (2007). Event history models for capture-recapture surveys with passively marked individuals.
• Schweder, Tore & Sadykova, Dinara (2007). Event history models for capture-recapture surveys with passively marked individuals.
• Schweder, Tore & Sadykova, Dinara (2007). Rough Modeling of complex photo-ID data for BCB bowhead whales.
• Schweder, Tore; Sadykova, Dinara; Rugh, D.J. & Koski, W.R (2007). Modeling of complex photo-ID data for BCB bowhead whales.
• Jorde, Per Erik; Schweder, Tore & Stenseth, Nils Christian (2004). The Bering-Chukchi-Beaufort stock of bowhead whales: one homogenous population?
• Schweder, Tore (2003). Statistikkens historie i Norge � faktisk uten statistikere? Tidsskrift for samfunnsforskning. ISSN 0040-716X. 44, p. 309–318.
• Schweder, Tore (2003). Sjangerbrudd eller vitenskapelig uredelighet i Lomborgsaken? Økonomisk forum. ISSN 1502-6108. 8(3), p. 1–4.
• Aldrin, Magne; Schweder, Tore & Holden, Marit (2002). Spatial distribution of whales based on the Norwegian Minke Whale Survey 1996-2001. Ukjent.
• Schweder, Tore (2002). Forkludring av vitenskapelig usikkerhet - erfaringer fra Hvalfangstkommisjonen. Cicerone. ISSN 0804-0508. p. 13–15. Show summary

  Forskere kan fuske på flere måter. En av dem er å forkludre den vitenskapelige usikkerheten ved å konstruere opp eller provosere fram unødige uenigheter og kontroverser. Dette har skjedd ved flere anledninger i Den internasjonale hvalfangskomisjonen.

• Schweder, Tore (2002). The history of statistics in Norway - told by historians. Show summary

  Lie, E. and Roll-Hansen, H. 2001. Faktisk talt - statistikkens historie i Norge (Factually speaking - The history of statistics in Norway), Universitetsforlaget, is written by two historians. I will comment on this book of 481 pages by asking two questions: (i) What is statistics to the historians, and what do they see as the place of statistics in in the shaping of the Norwegian society? And (ii) what have they found that is of particular interest to the general historian of statistics? Among other things, the authors have brought to the light a debate between Anders Kiær who used his representative method (survey sampling) to investigate the costs of introducing a public and universal pension scheme for old and disabled (proposed in 1894), and Jens Hjorth who used actuarial and statistical methods to argue that Kiær's survey gave biased results. Hjorth won the debate, and Kiær became silent about his representative method - while survey sampling was gaining growing attention internationally.

• Schweder, Tore (2002). Frequentist versions of posteriors and priors. Show summary

  Confidence distributions are Neyman's interpretation of Fisher's fiducial distributions. They are the frequentist's analogues of Bayesian priors and posteriors. The quantiles of a confidence distribution are end points of confidence intervals for the parameter in question. To combine a prior confidence distribution with the likelihood of new data, it must be converted to a likelihood summarizing the past data. The two likelihood components are then multiplied together, and posterior confidence distributions are obtained for the parameters of interest, often through a parametric bootstrap experiment. The likelihood related to a confidence distribution is in general different from the confidence density. A version of the Neyman-Pearson theorem is proved for confidence distributions. The frequentist approach is illustrated on capture-recapture data for bowhead whales, and is compared to the Bayesian approach with respect to bias and other issues

• Schweder, Tore (2001). Statistical Methods, History of: Post-1900. In Smelser, Neil J. & Baltes, Paul B (Ed.), International Encyclopedia of the Social & Behavioral Sciences. Elsevier. ISSN 0-08-043076-7. p. 15031–15037.
• Schweder, Tore (2001). Skepsisens plass i biologien - om falske funn og fordreid usikkerhet. Biolog. ISSN 0801-0722. 19(3/4), p. 6–12. Show summary

  På bakgrunn av diskusjon om parapsykologi og om hval og hvalfangst innen IWC, settes sunn skepsis opp mot notorisk skepsis av kverulantisk art. Usunn og vedvarende skepsis kan undergrave forskningsprosessens integritet, og kan i ekstreme tilfeller regenes som uskikk i forskningen, på linje med fabrikasjon og falsifikasjon.

• Schweder, Tore (2001). The Neyman-Pearson lemma for confidence distributions.
• Schweder, Tore (2001). Discrete distance sampling with difficulties.
• Schweder, Tore (2001). Fishers paradigmerevolusjon, et 79-års jubileum.
• Schweder, Tore (2001). Olav Reiersøl - statistiker, økonometriker og esperantist. Show summary

  Reiersøl var professor i matematisk statistikk fra 1961. Før det var han dosent og professor i matematikk, men hele tiden matematisk statistiker. Han døde i februar, nesten 93 år gammel. Reiersøls hovedfunn var at den enkleste konfluensanalysesmodellen til Frisch bare var uidentifiserbar når de latente variablene var normalfordelte. Hva betyr dette, hvorfor er det et viktig funn og hvordan kom Reiersøl til å interessere seg for dette spørsmålet? Hva ellers fant Reiersøl i sin forskning? Var han like en like original forsker som person, veileder og lærer?

• Schweder, Tore (2001). Minnetale over Olav Reiersøl.
• Schweder, Tore (2001). Abundance estimation from photo-identification data: confidence distributions and reduced likelihood for bowhead whales off Alaska.
• Schweder, Tore (2001). Revolusjoner og kontrarevolusjoner i teoretisk statistikk - kan frekventistisk Bayesianisme bringe varig fred?
• Schweder, Tore (2000). Frequentist versions of posteriors and priors. Show summary

  Confidence distributions (Fisher's fiducial distributions) are the frequentist's analogues of Bayesian priors and posteriors. The quantiles of a confidence distribution are end points of confidence intervals for the parameter in question. To combine a prior confidence distribution with the likelihood of new data, it must be converted to a likelihood summarizing the past data. The two likelihood components are then multiplied together, and posterior confidence distributions are obtained for the parameters of interest. This frequentist approach is compared to the Bayesian approach with respect to bias and other issues.

• Schweder, Tore (2000). Confidence distributions and likelihood. Show summary

  Confidence distributions are the frequentist's analogues of Bayesian priors and posteriors. Being a frequentist concept, the possible bias in a confidence distribution is well defined. Approximately unbiased posterior confidence distributions are obtained by bootstrapping of the likelihood based on the data and on possible prior confidence distributions based on previous data. As distinct from Bayesian analysis, information on the probability basis of a prior distribution is necessary to combine it with the data likelihood. Being a likelihood analysis, no problem arise if there are more or fewer prior distributions (with corresponding likelihood components) than there are free parameters in the model.

• Schweder, Tore (2000). Integrative fish stock assessment by frequentist methods: confidence distributions and likelihoods for bowhead whales. Show summary

  Frequentism in theoretical statistics evolved from R.A. Fisher's paradigmatic revolution in 1922, which partly was against the then prevailing Bayesianism. We now see a counter-revolution in fisheries and also elsewhere: back to Bayes. Is it necessary to depart from Fisher's methodology to use distributions as inputs and outputs of statistical analysis, and to integrate diverse data? Or can Fisher deliver the main attractions of Bayes, without some of the disturbing shortcomings? The frequentist methodology to be sketched is illustrated on data concerning bowhead whales. It involves the integration of diverse data, via the likelihood; the use of confidence distributions for inference about interest parameters; and obtaining confidence distributions and their accompanying reduced likelihoods through simulation experiments. A reduced likelihood summarizes the information in the data regarding a specific parameter, and might be used in later meta analyses. The approach might be attractive in the scientific context, where subjectivity should be kept to a minimum, where results should be unbiased and where the statistical uncertainty needs to be presented in the format of a distribution.

• Schweder, Tore (2000). Confidence distributions and reduced likelihood.
• Schweder, Tore (2000). Bør høye kvoter kappes ned? Bioøkonomisk modellering og simulering av torskefisket.
• Schweder, Tore (2000). Bør høye kvoter kappes ned? Bioøkonomisk modellering og simulering av torskefisket. Show summary

  Fisket reguleres nå stort sett på biologisk grunnlag. Kvotene varierer kraftig. Systemet i Barentshavet er modellert og simulering viser at lønnsomheten i fisket og samfunnets ressursrente bedres ved å kappe kvotene ned til et velvalgt øvre tak når de er høye. Overraskende nok blir ikke fangstene redusert i det lange løp ved fornuftig kvotekapping. En geometrisk versjon av den stokastiske Ornstein-Uhlenbeck prosessen blir også diskutert i dette perspektivet.

• Diekert, Florian Klaus; Schweder, Tore & Lund, Kristen (2014). From Open-Access to Individual Quotas: Disentangling the Effects of Policy Reform and Environmental Changes in the Norwegian Coastal Cod Fishery. Økonomisk Institutt, UiO. ISSN 0809-8786.
• Witting, Lars & Schweder, Tore (2008). Lower confidence bound on population status from catch sex ratio: applied to minke whales off West Greenland. International Whaling Commission. Show summary

  Lower confidence bounds on carrying capacity is estimated by parametric bootstrapping in the case of infinte maximum likelihood estimate.

• Aldrin, Magne; Huseby, Ragnar Bang & Schweder, Tore (2006). Variants of the Catch Limit Algorithm. Norsk Regnesentral.
• Aldrin, Magne Tommy; Storvik, Bård & Schweder, Tore (2006). Standardized catch per unit effort in minke whaling in Norwegian waters, 1952-1983 and 1993-2004. Norsk Regnesentral.
• Aldrin, Magne; Huseby, Ragnar Bang & Schweder, Tore (2006). Simulation trials for a re-tuned Catch Limit Algorithm. Norsk Regnesentral.
• Aldrin, Magne & Schweder, Tore (2005). ScenarioC - sluttrapport. Norsk Regnesentral.
• Hagen, Gro Synøve & Schweder, Tore (2005). Scenario C: A program documentation. Norsk Regnesentral.
• Aldrin, Magne & Schweder, Tore (2005). Revision of RMP – Status of ongoing work at the Norwegian Computing Center. IWC/SC/57/RMP3. International Whaling Commission.
• Schweder, Tore; Jorde, Per Erik & Stenseth, Nils Christian (2005). Temporal genetic pattern in BCB bowhead whales in the fall migration at Barrow: a reflection of a structured population? IWC/SC/57/BRG10. International Whaling Commission.
• Zhu, Mian; Schweder, Tore & Hagen, Gro Synøve (2004). Scenario-C: The cod predation model. Norsk Regnesentral.
• Hagen, Gro Synøve; Høst, Gudmund & Schweder, Tore (2003). Harp Seal in the Scenario-C Model. Norsk Regnesentral.
• Hagen, Gro Synøve; Høst, Gudmund & Schweder, Tore (2002). Analyse av replikatdata fra Vestfjorden 2001. Norsk Regnesentral.
• Fleischer, Luis A. & Schweder, Tore (2002). Gray whales on their winter grounds in Baja California Sur, México (1980-1998). International Whaling Commission. 54(BRG11). Show summary

  Temporal and seasonal patterns of abundance of adults and calves were estimated by generalized linear models from weakly counts obtained from shipborn and aerial surveys.

• Berg, Erlend; Schweder, Tore & Tvete, Ingunn Fride (2001). Statistisk modellering av kommersielle fangstdata; en illustrasjon basert på trålfangster av torsk i 1999. Norsk Regnesentral.
• Aldrin, Magne; Holden, Marit & Schweder, Tore (2001). Estimation of a Neyman-Scott process from line transect data by a one-dimensional K-function. Norsk Regnesentral.
• Schweder, Tore & Hjort, Nils Lid (2001). Confidence and Likelihood. Økonomisk institutt. ISSN 0801-1117.
• Hirst, David; Høst, Gudmund; Schweder, Tore; Fotland, Åge; Jakobsen, Tore & Skaug, Hans Julius [Show all 8 contributors for this article] (2000). Towards a statistical model for the uncertainty in fisheries data for stock asssessment in the Barents Sea. Norsk Regnesentral.
• Schweder, Tore & Hjort, Nils Lid (1999). Frequentist analogues of priors and posteriors. Department of Mathematics, University of Oslo. ISSN 82-553-1174-2.

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