Multivariate Covariance Generalized Linear Models

We propose a general framework for non-normal multivariate data analysis called multivariate covariance generalized linear models (McGLMs), designed to handle multivariate response variables, along with a wide range of temporal and spatial correlation structures defined in terms of a covariance link function combined with a matrix linear predictor involving known matrices. The method is motivated by three data examples that are not easily handled by existing methods. The first example concerns multivariate count data, the second involves response variables of mixed types, combined with repeated measures and longitudinal structures, and the third involves a spatio-temporal analysis of rainfall data. The models take non-normality into account in the conventional way by means of a variance function, and the mean structure is modelled by means of a link function and a linear predictor. The models are fitted using an efficient Newton scoring algorithm based on quasi-likelihood and Pearson estimating functions, using only second-moment assumptions. This provides a unified approach to a wide variety of different types of response variables and covariance structures, including multivariate extensions of repeated measures, time series, longitudinal, spatial and spatio-temporal structures.Comment: 21 pages, 5 figure

Self-Similarity and Lamperti Convergence for Families of Stochastic Processes

We define a new type of self-similarity for one-parameter families of stochastic processes, which applies to a number of important families of processes that are not self-similar in the conventional sense. This includes a new class of fractional Hougaard motions defined as moving averages of Hougaard L\'evy process, as well as some well-known families of Hougaard L\'evy processes such as the Poisson processes, Brownian motions with drift, and the inverse Gaussian processes. Such families have many properties in common with ordinary self-similar processes, including the form of their covariance functions, and the fact that they appear as limits in a Lamperti-type limit theorem for families of stochastic processes.Comment: 23 pages. IMADA preprint 2010-09-0

Svenskt ortnamnslexikon

Mats Wahlberg: Svenskt ortnamnslexikon. Andra upplagan. Institutet för språk och folkminnen 2016. 434 sider. Pris 350 SEK

Size-dependent escape risk of lumpfish (Cyclopterus lumpus) from salmonid farm nets

In the last decade, the salmon aquaculture industry has considerably increased the use of lumpfish juveniles as cleaner fish. Potential escape of reared lumpfish into the wild may spread diseases or genetically contaminate wild stocks. The guidelines for minimum sizes of cleaner fish to use in aquaculture cages are currently based on simple mesh penetration tests. However, these guidelines do not consider the potential compressibility of fish or changes in mesh state due to factors such as sea conditions and maintenance operations. This study shows that the industry-recommended minimum stocking sizes for a given mesh size may result in escape risk and that ignoring fish compressibility and mesh state can lead to underestimation of the lumpfish sizes that are able to escape. Our results can be used to develop new guidelines that will contribute to reduced escape of lumpfish from salmonid farms and lessen the potential environmental consequences.acceptedVersio

Christen Hansen Elstrups dagbog: et gensyn og et gennemsyn

I 1986 udgav Landbohistorisk Selskab en bondedagbog af den alsiske bonde Christen Hansen. Udgaven byggede på en afskrift ved Christine Knudsen. artiklen udbygger kendskabet til overleveringshistorien og sandsynliggør, at hendes afskrift bygger på en ældre, foretaget af hendes far Knud Knudsen. Denne afskrift er også benyttet af Knud Knudsens bror, Christian Knudsen, der gengiver en række uddrag. Enkelte af disse rækker ud over den tekst, der er udgivet i 1986, og bringes her in ekstenso

Bondens horisont. Stednavne som udtryk for bondebefolkningens omverdensorientering.

I artiklen fremdrages eksempler på, at marknavne kan afspejle en bondehorisont, der rakte ud over det lokale. Ganske vist var de fleste knyttet til lokale natur- og personforhold, men der var også marknavne, som henviser til fremmede folk og steder, Danmarkshistorien eller en by som Roskilde, der optræder i marknavne spredt over Sjælland. Det er også slående, at nogle ellers ikke så almindelige personnavne er knyttet til marker mange steder

Fra natur til kultur - navneforskningens metodik

Artiklen undersøger både ældre navne på den dyrkede jord og navne på egentlige naturelemter. Forfatteren konkluderer: Naturen står i centrum, når vi betragter vores ældste navneskat, men navngivningen er ikke blind eller tilfældig, og hver gang vi finder et stednavn i naturen, må vi huske, at det er givet af et menneske til brug i den menneskelige interaktion, og at det pågældende stykke natur dermed er indtaget under begrebet kultur