Stochastic Dominance Portfolio Analysis of Forestry Assets

We consider the forestry decision-making and harvesting problem from the perspective of financial portfolio management, where harvestable forest stands constitute one of the liquid assets of the portfolio. Using real data from Finnish mixed borealis forests and from the Helsinki stock exchange, we investigate the effect of trading the timber stock together with the forest land, or without the land (i.e., harvesting), on the portfolio efficiency. As our research methodology, we utilize the general Stochastic Dominance (SD) criteria, focusing on the recent theoretical advances in analyzing portfolio diversification within the SD framework. Our findings shed some further light on the question of how to model the forestry planning problem, and provide some comparative evidence of the applicability of the alternative SD test approaches.Forest Management, Portfolio Optimization, Stochastic Dominance, Diversification

Computing the output distribution and selection probabilities of a stack filter from the DNF of its positive Boolean function

Many nonlinear filters used in practise are stack filters. An algorithm is presented which calculates the output distribution of an arbitrary stack filter S from the disjunctive normal form (DNF) of its underlying positive Boolean function. The so called selection probabilities can be computed along the way.Comment: This is the version published in Journal of Mathematical Imaging and Vision, online first, 1 august 201

Hot electron-induced electrogenerated chemiluminescence of Ru(bpy)(3)(2+) chelate at a pointed active metal cathode in fully aqueous solutions

Tris(2,2'-bipyricline)ruthenium(II) chelate exhibits strong electrogenerated chemiluminescence during cathodic high-voltage pulse-polarization of pointed Pt electrode in aqueous solutions. The present method is based on a field emission or other type of tunnel emission of hot electrons into an aqueous electrolyte solution. The method allows the detection of tris(2,2'-bipyridine)ruthenium(II) and its derivatives below nanomolar concentration levels and yields linear log-log calibration plots spanning several orders of magnitude of concentration. (C) 2016 Elsevier B.V. All rights reserved

Pääsyy vai syypää - potilasturvallisuuskulttuuri ratkaisee

Hyvä kulttuuri on kiinni yksilöistä. Se ei kuitenkaan synny itsestään, vaan siihen tarvitaan tietoa sekä arvoja ja asenteita tukevaa johtamista. Vaaratapahtumista täytyy saada puhua ja oppia ilman pelkoa

Can we assess teaching quality on the basis of student outcomes? A stochastic frontier application

This paper proposes a new application of Stochastic Frontier Analysis (SFA) for estimating the student performance gap and how this can be used to assess changes of teaching quality at the individual unit-of-study level (module-level). Although there have been other examples in the literature that assess ‘efficiency’ in student outcomes, this is the first study that proposes the use of SFA specifically at the module level and with the goal of creating an aggregate measure of ‘quality’, thus avoiding the known issue of the statistical inconsistency of unit-specific SFA estimates. A case study is presented on how the approach can be applied in practice, with discussion on potential implementation issues. This paper is targeted to academics and policy makers that are interested in the quantitative assessment of student outcomes and specifically to those who want to assess how changes in module structure and/or delivery have affected said student outcomes

Mitä vapaaehtoiset vaaratapahtumailmoitukset kertovat?

VertaisarvioituLÄHTÖKOHDAT Yli 300 sosiaali- ja terveydenhuollon organisaatiota käyttää vapaaehtoista vaaratapahtumien HaiPro-raportointijärjestelmää. Ilmoituksia on tehty yli miljoona. MENETELMÄT Analysoimme tilastollisesti valtaosan ilmoituksista, yhteensä 847 492. TULOKSET Ilmoitusten vuotuinen määrä on kasvussa. Kolmannes koski läheltä piti -tilanteita. Potilaaseen kohdistuneet haitat olivat useimmiten korkeintaan lieviä. Yleisimmin ilmoitukset koskivat lääke- ja nestehoitoa, tapaturmia tai tiedonkulkua. Potilaille oli kerrottu haitoista lähes aina. Lääkärit ilmoittivat vain 2 % tapauksista, ja ilmoituksissa painottuivat vakavat tapahtumat. Kehittämistoimenpiteitä esitettiin harvoin. PÄÄTELMÄT Lääkärien ilmoitusaktiivisuus oli heikko. Syynä lienee huomion painottuminen lääketieteeseen ja mestari-kisällimallin mukaiseen henkilökohtaiseen ohjaukseen enemmän kuin prosesseihin. Tämä ei yleensä johda moniammatilliseen oppimiseen.Peer reviewe

Warm summers and rich biotic communities during N-Hemisphere deglaciation

Detailed studies on fossil remains of plants or animals in glacial lake sediments are rare. As a result, environmental conditions right at the moment of deglaciation of the large N-Hemisphere ice-sheets remain largely unknown. Here we study three deglacial phases of the Fennoscandian Ice Sheet as a unique, repeated element in a long sediment record preserved at Sokli in northern Finland. We summarize extensive multi-proxy data (diatoms, phytoliths, chironomids, pollen, spores, non-pollen palynomorphs, macrofossils, lithology, loss-on-ignition, C/N) obtained on glacial lake sediments dated to the early Holocene (ca. 10 kyr BP), early MIS 3 (ca. 50 kyr BP) and early MIS 5a (ca. 80 kyr BP). In contrast to the common view of an unproductive ice-marginal environment, our study reconstructs rich ecosystems both in the glacial lake and along the shores with forest on recently deglaciated land. Higher than present-day summer temperatures are reconstructed based on a large variety of aquatic taxa. Rich biota developed due to the insolation-induced postglacial warming and high nutrient levels, the latter resulting from erosion of fresh bedrock and sediment, leaching of surface soils, decay of plant material under shallow water conditions, and sudden decreases in lake volume. Aquatic communities responded quickly to deglaciation and warm summers and reflect boreal conditions, in contrast to the terrestrial ecosystem which responded with some delay probably due to time required for slow soil formation processes. Birch forest is reconstructed upon deglaciation of the large LGM ice-sheet and shrub tundra following the probably faster melting smaller MIS 4 and MIS 5b ice-sheets. Our study shows that glacial lake sediments can provide valuable palaeo-environmental data, that aquatic biota and terrestrial vegetation rapidly accommodated to new environmental conditions during deglaciation, and that glacial lake ecosystems, and the carbon stored in their sediments, should be included in earth system modeling.Peer reviewe

Postglacial succession of caddisfly (Trichoptera) assemblages in a central European montane lake

The Bohemian Forest lakes, situated along the Czech-German-Austrian border, were strongly affected by atmospheric acidifi- cation between the 1950s and the late 1980s. The subsequent chemical recovery of the lake water should precede and enable a biological recovery, including changes in caddisfly (Insecta: Trichoptera) assemblages. Nevertheless, local pre-acidification data and detailed knowledge of the lake district history are missing, making evaluation of lake recovery difficult. We performed high-resolution analysis of caddisfly remains in a 2.2 m long sediment profile from Prášilské Lake covering the complete history of the lake-catchment evolution. Caddisfly larvae are good indicators of environmental conditions and their subfossil remains are well preserved in unconsolidated waterlaid sediments. A total of 10 caddisfly morpho-taxa were found providing a record from 11,400 cal. yr. BP to the present. With the exception of Athripsodes aterrimus, all identified species are currently present in the Bohemian Forest glacial lakes or their inflow streams but not all of them are documented in Prášilské Lake. The caddisfly fauna consisted of acid-resistant, acid-tolerant and eurytopic species since the Early Holocene. Based on our results, the acid, dystrophic state of Prášilské Lake has been occurring since the lake formation. We conclude that the first signs of natural acidification appeared not later than during the Holocene onset in the Bohemian Forest region. Furthermore, we did not detect any abrupt changes in the species composition connected to the period of anthropogenic acidification during the twentieth century. This study provides for the first time a record of postglacial succession of caddisfly assemblages in a central European mountain lake

Algorithms and Bounds for Drawing Directed Graphs

In this paper we present a new approach to visualize directed graphs and their hierarchies that completely departs from the classical four-phase framework of Sugiyama and computes readable hierarchical visualizations that contain the complete reachability information of a graph. Additionally, our approach has the advantage that only the necessary edges are drawn in the drawing, thus reducing the visual complexity of the resulting drawing. Furthermore, most problems involved in our framework require only polynomial time. Our framework offers a suite of solutions depending upon the requirements, and it consists of only two steps: (a) the cycle removal step (if the graph contains cycles) and (b) the channel decomposition and hierarchical drawing step. Our framework does not introduce any dummy vertices and it keeps the vertices of a channel vertically aligned. The time complexity of the main drawing algorithms of our framework is $O(kn)$, where $k$ is the number of channels, typically much smaller than $n$ (the number of vertices).Comment: Appears in the Proceedings of the 26th International Symposium on Graph Drawing and Network Visualization (GD 2018