Search results for "Drift"
showing 10 items of 321 documents
Experimental Evolution in Viruses
2011
Experiments in which evolution takes place in real time can help us establish cause–effect relationships that are difficult to infer from the analysis of natural populations. The simplicity, rapid evolution and biomedical relevance of viruses make them a particularly interesting model system for experimental evolution. Bacterial, animal and plant viruses can be passaged under a variety of conditions, either in simple cell culture systems or in vivo to test population biology hypotheses, study the genetic basis of evolution, or predict evolutionary change in nature. Experimental evolution is a conceptually simple and flexible tool which allows us to address issues ranging from the molecular …
Do island plant populations really have lower genetic variation than mainland populations? Effects of selection and distribution range on genetic div…
2015
Ecological and evolutionary studies largely assume that island populations display low levels of neutral genetic variation. However, this notion has only been formally tested in a few cases involving plant taxa, and the confounding effect of selection on genetic diversity (GD) estimates based on putatively neutral markers has typically been overlooked. Here, we generated nuclear microsatellite and plastid DNA sequence data in Periploca laevigata, a plant taxon with an island–mainland distribution area, to (i) investigate whether selection affects GD estimates of populations across contrasting habitats; and (ii) test the long-standing idea that island populations have lower GD than their mai…
Essays on Auditors’ Judgments and Decisions in Negotiation and Communication
2022
Paper III is excluded from the dissertation until it will be published. Auditors conduct various audit tasks during an audit in order to arrive at an audit opinion regarding whether the financial statements are fairly presented in accordance with the applicable financial reporting framework. To perform these audit tasks and arrive at a decision about the audit opinion, auditing standards require auditors to exercise their professional judgment. From this requirement, two important terms emerge, judgment and decision. Bonner (1999, p. 385) defines judgment as “forming an idea, opinion, or estimate about an object, an event, a state, or another type of phenomenon,” and a decision as “making u…
Concept Drift Detection Using Online Histogram-Based Bayesian Classifiers
2016
In this paper, we present a novel algorithm that performs online histogram-based classification, i.e., specifically designed for the case when the data is dynamic and its distribution is non-stationary. Our method, called the Online Histogram-based Naïve Bayes Classifier (OHNBC) involves a statistical classifier based on the well-established Bayesian theory, but which makes some assumptions with respect to the independence of the attributes. Moreover, this classifier generates a prediction model using uni-dimensional histograms, whose segments or buckets are fixed in terms of their cardinalities but dynamic in terms of their widths. Additionally, our algorithm invokes the principles of info…
Leans 14 ledelsesprinsipper i opplevelsesnæringen : En casestudie av Dyreparken
2017
Masteroppgave økonomi og administrasjon BE501 - Universitetet i Agder 2017 Formålet med oppgaven har vært å forklare overføringen av de 14 ledelsesprinsippene innen Lean til opplevelsesnæringen og samtidig se på hvilke effekter dette kan resultere i. Lean handler om å skape mest mulig kundeverdi med minst mulig ressurser. Dette gjøres blant annet ved å fokusere på flyt, oversiktlige prosesser og kontinuerlig forbedring (Wig, 2013). De 14 ledelsesprinsippene er Jeffrey K. Likers sammenfatning av Lean. Ledelsesprinsippene er delt inn i hovedkategoriene: langsiktig filosofi, riktige prosesser skaper riktige resultater, utvikle ansatte og partnere og løse kontinuerlig grunnleggende problemer, s…
The value relevance of losses revisited: the importance of earnings aggregation
2011
Accepted version of an article published in the journal: Global Business and Economics Review. Also available from the publisher at: http://dx.doi.org/10.1504/GBER.2011.040728 Prior research has suggested that earnings explain a larger portion of the variation in stock returns when disaggregated into components. This study shows that the increase in explanatory power stems primarily from disaggregation of negative earnings. When accounting earnings are sufficiently disaggregated into items, there is no longer a statistical difference in the value relevance of positive and negative earnings. Thus, negative earnings are also useful to stock investors. The findings are attributed to earnings p…
Disentangling composite colour patterns in a poison frog species
2008
A phylogenetic approach was performed to infer whether variation in conspicuous colour-patterns of a poison frog (Dendrobatidae: Dendrobates tinctorius) has evolved neutrally or under selection. Colour and pattern were split into components that were separately analysed and subsequently re-grouped via principal component analysis. This revealed four different ‘displayed’ factors on the dorsal and lateral views versus one ‘concealed’ factor on the ventral view. Based on the assumption that current patterns of trait variation contain information about the evolutionary history of the phenotype, we correlated these trait components to a neutrally evolving gene fragment (cytochrome b). The conce…
Amorphous hydrogenated carbon (a-C:H) depositions on polyoxymethylene: Substrate influence on the characteristics of the developing coatings
2016
Abstract After oxygen plasma treatment polyoxymethylene (POM) material was exposed to acetylene plasma to progressively deposit two different types of amorphous hydrogenated carbon (a-C:H) films. Radio frequency plasma-enhanced chemical vapor deposition (RF-PECVD) was used to generate both plasma processes. The surface morphology of the coated samples has been investigated by atomic force microscopy (AFM) and their chemical composition by Diffusive Reflectance Infrared Fourier Transform (DRIFT) and Raman spectroscopy. Results revealed the absence of a solid interlayer formation between the a-C:H films and POM. The in sequence exposure of oxygen and acetylene plasma on POM substrate prevents…
Similar but Different? The influence of job satisfaction, organizational commitment and person-job fit on individual performance in the continuum bet…
2022
Permanent organizations and temporary organizations, such as projects, represent two poles of a continuum of organizational temporariness. The literature has shown that organizational temporariness can influence organizational outcomes and employee behavior. Using a sample of 341 members of temporary organizations, we investigate job satisfaction and organizational commitment in a permanent organization and person-job fit in a temporary organization as antecedents of employee performance. We further examine how the degree of organizational temporariness moderates these relationships. The findings show that job satisfaction and organizational commitment negatively influence employee performa…
Node co-activations as a means of error detection : Towards fault-tolerant neural networks
2022
Context: Machine learning has proved an efficient tool, but the systems need tools to mitigate risks during runtime. One approach is fault tolerance: detecting and handling errors before they cause harm. Objective: This paper investigates whether rare co-activations – pairs of usually segregated nodes activating together – are indicative of problems in neural networks (NN). These could be used to detect concept drift and flagging untrustworthy predictions. Method: We trained four NNs. For each, we studied how often each pair of nodes activates together. In a separate test set, we counted how many rare co-activations occurred with each input, and grouped the inputs based on whether its class…