Paksuhäntäiset jakaumat ja riskimitat

In this thesis, we explore financial risk measures in the context of heavy-tailed distributions. Heavy-tailed distributions and the different classes of heavy-tailed distributions will be defined mathematically in this thesis but in more general terms, heavy-tailed distributions are distributions that have a tail or tails that are heavier than the exponential distribution. In other words, distributions which have tails that go to zero more slowly than the exponential distribution. Heavy-tailed distributions are much more common than we tend to think and can be observed in everyday situations. Most extreme events, such as large natural phenomena like large floods, are good examples of heavy-tailed phenomena. Nevertheless, we often expect that most phenomena surrounding us are normally distributed. This probably arises from the beauty and effortlessness of the central limit theorem which explains why we can find the normal distribution all around us within natural phenomena. The normal distribution is a light-tailed distribution and essentially it assigns less probability to the extreme events than a heavy-tailed distribution. When we don’t understand heavy tails, we underestimate the probability of extreme events such as large earthquakes, catastrophic financial losses or major insurance claims. Understanding heavy-tailed distributions also plays a key role when measuring financial risks. In finance, risk measuring is important for all market participants and using correct assumptions on the distribution of the phenomena in question ensures good results and appropriate risk management. Value-at-Risk (VaR) and the expected shortfall (ES) are two of the best-known financial risk measures and the focus of this thesis. Both measures deal with the distribution and more specifically the tail of the loss distribution. Value-at-Risk aims at measuring the risk of a loss whereas ES describes the size of a loss exceeding the VaR. Since both risk measures are focused on the tail of the distribution, mistaking a heavy-tailed phenomena for a light-tailed one can lead to drastically wrong conclusions. The mean excess function is an important mathematical concept closely tied to VaR and ES as the expected shortfall is mathematically a mean excess function. When examining the mean excess function in the context of heavy-tails, it presents very interesting features and plays a key role in identifying heavy-tails. This thesis aims at answering the questions of what heavy-tailed distributions are and why are they are so important, especially in the context of risk management and financial risk measures. Chapter 2 of this thesis provides some key definitions for the reader. In Chapter 3, the different classes of heavy-tailed distributions are defined and described. In Chapter 4, the mean excess function and the closely related hazard rate function are presented. In Chapter 5, risk measures are discussed on a general level and Value-at-Risk and expected shortfall are presented. Moreover, the presence of heavy tails in the context of risk measures is explored. Finally, in Chapter 6, simulations on the topics presented in previous chapters are shown to shed a more practical light on the presentation of the previous chapters

"Erikoist luonnet se vaatii" : Elintarvikealan pienyrittäjänä toimiminen varsinaissuomalaisella maaseudulla 2020-luvulla

Tämän tutkimuksen kohteena ovat elintarvikealan pienyrittäjät, jotka työskentelevät muuttuvassa toimintaympäristössä, uudenlaisten raaka-aineiden ja tuotantotapojen parissa varsinaissuomalaisella maaseudulla 2020-luvulla. Tutkin sitä, miten yrittäjät näkevät omat vaikutusmahdollisuutensa sellaisiin nyky-yhteiskunnan haasteisiin kuten ilmastonmuutos ja maaseudun autioituminen. Tutkimusaineistona on Suomen maatalousmuseo Sarkan ja Turun Yliopiston etnologian oppiaineen kanssa keväällä 2020 yhteistyönä toteuttaman Maatalouden elintarviketeollisuuden nykydokumentointi -hankkeen tuloksena syntynyt haastatteluaineisto, yhteensä 19 teemahaastattelua. Hankkeeseen osallistui kaiken kaikkiaan 17 yritystä, joista valtaosa on pieniä perheyrityksiä. Kenttätyöt toteutettiin kevään 2020 aikana, jolloin saatiin myös tallennettua ajankohtaista tietoa maailmanlaajuisen koronapandemian vaikutuksista maatalouteen ja pienyrittäjien elinkeinoon. Tarkastelen maaseudun muuttuvaa toimintaympäristöä elintarvikealan yrittäjien näkökulmasta ja tutkin sitä, miten he kokevat yrittäjyyden osana jokapäiväistä arkeaan ja elinympäristöään. Tarkastelen yrittäjien kokemuksia moniäänistä tutkimusotetta hyödyntäen, jolloin yksilöiden kokemukset ja kulttuurin monimuotoisuus tulevat selkeämmin näkyviin. Tutkimusaineiston analysoinnissa olen käyttänyt kulttuurianalyysia, jonka avulla on mahdollista heijastaa jokapäiväisiä arjen asioita suurempiin yhteiskunnallisiin kysymyksiin. Tutkimukseni keskeisenä tuloksena on se, että yhä kiihtyvällä tahdilla muuttuva maailma on muuttanut elintarvikealan toimintaympäristöä monin eri tavoin ja vaatinut alan yrittäjiltä ketteryyttä ja sopeutumiskykyä. Myynnin ja markkinoinnin merkitys ovat korostuneet entisestään ja verkkokaupan suosio kasvanut koronapandemian aikana. Kuluttajat vaativat vastuullisesti tuotettuja, ekologisia ja hyvinvointia tukevia elintarvikkeita ja yrittäjien täytyy seurata herkästi erilaisia kulloinkin pinnalla olevia trendejä pysyäkseen ajan hermoilla. Yrittäjät pyrkivät huomioimaan ympäristöasiat laaja-alaisesti kaikessa yritystoiminnassaan ja kokevat toimintansa tukevan kestävää kehitystä ja maaseudun elinvoimaisuutta. Toiveena on, että yritystoiminnalle löytyy jatkaja omasta perheestä. Maaseudun pienyrittäjien kokemusten tarkastelu auttaa omalta osaltaan ymmärtämään sitä, miten moniulotteisesta ja -mutkaisesta kokonaisuudesta on kyse, kun puhumme maatalouden ja toimintaympäristöjen muutoksesta

Welche Rolle spielt das konstitutionelle Moment in der Pathogenese der Bothriocephalus-Anämie? 1 )

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Miljökuznetskurvan och Finland i ett historiskt perspektiv

Only abstract. Paper copies of master’s theses are listed in the Helka database (http://www.helsinki.fi/helka). Electronic copies of master’s theses are either available as open access or only on thesis terminals in the Helsinki University Library.Vain tiivistelmä. Sidottujen gradujen saatavuuden voit tarkistaa Helka-tietokannasta (http://www.helsinki.fi/helka). Digitaaliset gradut voivat olla luettavissa avoimesti verkossa tai rajoitetusti kirjaston opinnäytekioskeilla.Endast sammandrag. Inbundna avhandlingar kan sökas i Helka-databasen (http://www.helsinki.fi/helka). Elektroniska kopior av avhandlingar finns antingen öppet på nätet eller endast tillgängliga i bibliotekets avhandlingsterminaler.I detta arbete har jag granskat om det i Finland går att finna empiriska belägg för miljökuznetskurvan. Idén bakom miljökuznetskurvan är att utsläpp och annan miljöskadlig verksamhet först ökar i takt med BNP per person i länder med växande men låg BNP per person. Därefter förväntas den miljöskadliga verksamheten nå sin kulmen vid något specifikt värde på BNP per person för att sedan sjunka allt mera i takt med att inkomsterna ökar. Jag har med regressionsanalys undersökt om 11 utsläpp och övriga miljöindikatorer har följt en sådan utveckling under Finlands närhistoria. De miljöindikatorer som jag har granskat är utsläppen av koldioxid, CFC-föreningar, svaveldioxid och kväveoxider i luft, utsläppen av fosfor och kväve i vatten, spridningen av bekämpningsmedel, elförbrukning, förbränning av fossila bränslen, bruket av kärnkraft och totalförbrukningen av naturresurser. Urvalet baserar sig på Finlands officiella indikatorer på en hållbar utveckling från 2000. Uppgifterna om dessa och BNP per person härrör från Finlands Miljöcentral och Statistikcentralen. Av de granskade indikatorerna verkar utsläppen av CFC-gaser, svaveldioxid, fosfor, kväve och spridningen av bekämpningsmedel följa miljökuznetskurvor som når sina toppar vid värden på BNP per person på mindre än 19306€, 13125€, mindre än 13366€, högst 21348€ respektive 16707€. Utsläppen av koldioxid, kväveoxider, total elförbrukning, förbränningen av fossila bränslen, bruket av kärnkraft och den totala förbrukningen av naturresurser kan inte påvisas följa miljökuznetskurvor. I ljuset av mina resultat verkar det i Finland ha funnits samhälls- och marknadsmekanismer som gett upphov till en tendens för miljöskadlig verksamhet att följa en miljökuznetskurva. Samtidigt verkar kuznetskurvans uppkomst bero på en mängd olika faktorer som endast delvis påverkas av nivån på BNP per person. Mycket tyder på att kuznetskurvan lättare uppstår för föroreningar som beror på bruket av ersättningsbara kemikalier och industriella processer vars utsläpp kan renas till överkomliga kostnader än på diffusa utsläpp som kräver satsningar av stora delar av befolkningen

Does National power trigger ocean conservation?

States are reacting to the global crises of biodiversity and the provision of ecosystem services mainly through the expansion of their networks of protected areas. This reaction would have been boosted by the commitments made between the parties of the Convention on Biological Diversity, and facilitated by the opportunities offered by isolated territories, where economic interests are minimal. However, few studies have discussed the importance of national power as conservation conditionings, particularly in the ocean. In this regard, here we evaluate whether the relative extent of marine protected areas (MPAs) is related to different elements of national power. Following a quantitative approach and incorporating into analyses 155 countries, our models suggest that an increasing power (in terms of country size –land and ocean– and military capacity) is related to greater marine protection. Although these patterns could be initially associated with the ample human and economic resources of most powerful countries and with the opportunities provided by their overseas territories, different arguments would support national power elements as conservation drivers. Specifically, the exertion of such power through conservation could be linked to geopolitical strategies such as the (re)validation of a country's sovereignty over its Exclusive Economic Zone (EEZ), the greater regulation of the circulation and use of this space, the greater influence in the regional context, and the assurance in the provision of future ecosystem goods and services. In this way, changes in geopolitical conditions could affect MPAs, compromising the effective conservation of biodiversity and ecosystem processes, as well as the sustainable management of assets.Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; ArgentinaFil: Schauman, Santiago Augusto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; ArgentinaFil: Gandini, Patricia Alejandra. Universidad Nacional de la Patagonia Austral. Unidad Academica Caleta Olivia. Instituto de Cultura, Identidad y Comunicacion.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentin

Successful Amplification of DNA Specific for Finnish Borrelia burgdorferi Isolates in Erythema Chronicum Migrans but Not in Circumscribed Scleroderma Lesions

Early diagnosis of Borrelia burgdorferi infection, hampered by the absence of detectable antibodies in most patients with erythema chronicum migrans is important to prevent late-stage neurologic, rheumatologic, and skin disorders. Furthermore, B. burgdorferi has been claimed to be the causative agent in localized scleroderma (morphea). We used PCR amplification to search for B. burgdorferi outer surface protein OspA–specific sequences in DNA obtained from lesional skin biopsies on Finnish patients with clinically suspect erythema chronicum migrans, lymphocytoma, morphea, or with diverse skin manifestations and persistent high antibodies to B. burgdorferi flagellar antigen. Seronegative patients with other skin lesions served as controls. The amplicons obtained with primers specific for B. burgdorferi type strain B31 ospA sequence did not hybridize to the corresponding probes, and thus the DNA amplified from a Finnish B. burgdorferi erythema chronicum migrans skin isolate was sequenced. This 98-nucleotide sequence of ospA (332–429) showed 11% to 14% nucleotide divergence compared with the North American type strain (B31), several European strains, and an East Siberian tick strain. The sequence was almost identical (99%) to a Swedish isolate from acrodermatitis chronica atrophicans. Using oligonucleotides specific for the Finnish strain, a positive polymerase chain reaction – based hybridization was obtained in six of seven untreated erythema chronicum migrans patients infected in Finland or in Estonia, and in the lymphocytoma patient. Only two of the erythema chronicum migrans patients had IgG or IgM antibodies to flagellin. However, all seven morphea lesions as well as the other lesions were polymerase chain reaction negative. Polymerase chain reaction – based hybridization ofB. burgdoferi OspA gene from skin-derived DNA thus provides a sensitive and specific diagnostic tool. In conditions not unequivocally known to be caused by B. burgdorferi in morphea, this assay was negative. We also demonstrate that peri-Baltic B. burgdorferi isolates show homology in their OspA genes but differ from geographically more distant isolates