Improving the INLA approach for approximate Bayesian inference for latent Gaussian models

We introduce a new copula-based correction for generalized linear mixed models (GLMMs) within the integrated nested Laplace approximation (INLA) approach for approximate Bayesian inference for latent Gaussian models. While INLA is usually very accurate, some (rather extreme) cases of GLMMs with e.g. binomial or Poisson data have been seen to be problematic. Inaccuracies can occur when there is a very low degree of smoothing or "borrowing strength" within the model, and we have therefore developed a correction aiming to push the boundaries of the applicability of INLA. Our new correction has been implemented as part of the R-INLA package, and adds only negligible computational cost. Empirical evaluations on both real and simulated data indicate that the method works well

Unsupervised empirical Bayesian multiple testing with external covariates

In an empirical Bayesian setting, we provide a new multiple testing method, useful when an additional covariate is available, that influences the probability of each null hypothesis being true. We measure the posterior significance of each test conditionally on the covariate and the data, leading to greater power. Using covariate-based prior information in an unsupervised fashion, we produce a list of significant hypotheses which differs in length and order from the list obtained by methods not taking covariate-information into account. Covariate-modulated posterior probabilities of each null hypothesis are estimated using a fast approximate algorithm. The new method is applied to expression quantitative trait loci (eQTL) data.Comment: Published in at http://dx.doi.org/10.1214/08-AOAS158 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

Use of time-lapse cameras to monitor beetle activity on fruiting bodies of Fomitopsis pinicola

Insects and fungi are the major contributors to forest biodiversity. It is apparent that insects have an ecologically important effect on fungal communities in dead wood systems. Beetles frequently visit the fruiting bodies of polypore wood-decay fungi to feed on spores and have the potential to act as targeted dispersal vectors by carrying and disseminating fungal propagules. However, and despite the hypothesised importance of this interaction, we know little of who these beetle visitors are, when and how often they visit, or how long a typical visit lasts. In this study, beetle activity on fruiting bodies of Fomitopsis pinicola (Sw.) P.Karst. was monitored by using commercial time-lapse cameras at 11 different sites in Østmarka in Southern Norway. Insect visitation studies have traditionally relied on strenuous manual observations. The goal of this study was to evaluate the use of time-lapse cameras as an alternative to manual observations of beetle activity on polypores, something which has not previously been attempted. Despite various technical difficulties and a high proportion of images being of poor quality (> 60%), the time-lapse cameras were able to generate a large amount of high-quality image data, from which the activity of three beetle species could be estimated. The image quality did not allow for detailed taxonomical identification of small beetle species (> 5 mm), so time-lapse cameras should be seen as a supplement to traditional methods as opposed to a complete replacement. The method can without doubt be improved and developed further. Time-lapse cameras thus have great potential for use in entomological research focusing on fungus-insect interactions.submittedVersionM-ECO

Indirect genomic effects on survival from gene expression data

A novel methodology is presented for detecting and quantifying indirect effects on cancer survival mediated through several target genes of transcription factors in cancer microarray data

«Å sovne er som å lekke, tenker jeg» En lesning av Søvnens lekkasje av Beate Grimsrud, med vekt på drømmeprosesser

Oppgaven er en analyse av Søvnens Lekkasje av Beate Grimsrud (2007) med fokus på hvordan drømmeprosesser fremstilles. Dette blir pekt på gjennom å analysere den navnløse hovedpersonens indre reise i sine egne drømmeprosesser. I drømmeprosessene møter hovedpersonen Den Høye som blir viktig i fremstillingen av drømmeprosessene, samt analysen av den gjennomgående karakteren av underliggjøring som fremtrer i romanen. I den oppsummerende delen argumenterer jeg for hvordan man kan tolke romanen som et uttrykk for en utopi for å bidra til en endring i verden.The thesis is an analysis of Søvnens lekkasje by Beate Grimsrud (2007) with a focus on how dream processes are presented. This is pointed out by analyzing the nameless protagonist's inner journey in her own dream processes. In the dream processes, the main character encounters Den Høye, which becomes important in the presentation of the dream processes, as well as the analysis of the general character of estrangement that appears in the novel. In the summary section, I argue for how to interpret the novel as an expression of a utopia to contribute to a change in the world

Lærerspørsmål og elevdeltakelse i matematiske helklassesamtaler.

I Kunnskapsløftet 2020 blir det i kompetansemålene for matematikk lagt vekt på at elevene skal forklare, resonnere, diskutere og reflektere i faget. Å lede produktive matematiske samtaler i klasserommet, kan for mange lærere være krevende, men lærerens bruk av spørsmål har vist seg å være svært betydningsfullt i dette arbeidet. Tidligere har det blitt forsket en del på lærerspørsmål, men forskningsfeltet trekker frem at det er behov for mer kunnskap på dette området. Denne studiens problemstilling er: «Hvordan kan ulike typer lærerspørsmål påvirke elevenes muligheter og begrensninger for elevdeltakelse i matematiske helklassesamtaler?». Med elevdeltakelse menes det at elevene forklarer, resonnerer, argumenterer og reflekterer. Forskningsprosjektets datamateriale ble samlet inn på 10. trinn i form av videoobservasjon. I løpet av to uker ble seks undervisningsøkter i temaet personlig økonomi filmet. Lærerens spørsmål og elevenes respons i helklassesamtalene, ble analysert etter Boaler og Brodies spørsmålskategorier og Ilarias elevresponskategorier. Resultatet viser at ingen av spørsmålskategoriene til Boaler og Brodie utmerket seg spesielt i studien, men læreren stilte allikevel flest spørsmål som ble kodet i kategorien samle informasjon. Videre viser resultatet at elevene responderte flest ganger med et elevsvar i kategorien tenke høyt på de spørsmålene som læreren stilte i temaet personlig økonomi. I tillegg til dette viser studiens resultat at lærerspørsmål i kategorien sondering, i flere tilfeller fremmet elevdeltakelse hvor elevene forklarte, resonnerte, diskuterte eller reflekterte i helklassesamtalene, sammenlignet med andre typer lærerspørsmål. I resultatkapittelet ble det også trukket frem hvordan ulike typer lærerspørsmål kan fremme eller hemme elevenes deltakelse i matematiske helklassesamtaler. Studiens datamateriale er basert på relativt få informanter, noe som fører til at det er behov for mer forskning på dette forskningsfeltet, før en kan trekke en konklusjon. Likevel kan studien gi en indikasjon på hvilke typer lærerspørsmål som kan være med på å fremme en slik type elevdeltakelse som blir trukket frem i kompetansemålene for matematikk i Kunnskapsløftet 2020.One of the aims in “Kunnskapsløftet 2020” is that the student is competent in using explanation, reasoning, discussion and reflection on the mathematical subject. To lead productive mathematical conversations in the classroom can be demanding for many teachers, but the teacher’s use of questions has proven to be very important in this work. The way that teachers use and formulate questions has been the subject of some previous research, but the scientific community points out that there is a need for more research on the subject. This thesis researches the question: «How can different types of teacher questions affect the opportunities and limitations for the students’ participation in mathematical whole-class discussions?”. This participation is, in “Kunnskapsløftet 2020”, emphasized as a type of communication that is preferred in the mathematical aims. This thesis data was collected in the 10th grade, using video observation. In a timespan of two weeks, six lessons on the topic of personal finance were filmed. The way that the teachers used and formulated questions, and the student’s responses were analyzed according to Boaler and Brodie´s question categories and Ilarias’ student response categories. The results of the data showed that none of Boaler and Brodie´s question categories was used to an extend in this study, but the teacher asked most questions in the category gathering information. Further, the results showed that most of the students’ responses were categorized in the category thinking aloud on the topic of personal finance. The results of the study also showed that questions that belong in the category probing, in several cases promoted student participation where the students explained, reasoned, discussed, or reflected in the whole-class discussion. This compared with questions from other categories. The results also showed how different types of questions can affect students’ opportunities and limitations for students’ participation in mathematical whole-class discussions. This thesis data is based on relatively few informants, which means that more research is needed in this field of research before a conclusion can be drawn. Nevertheless, the study can still indicate the types of teacher questions that provide opportunities and limitations for student participation in mathematical whole-class discussions