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  • Kullman, Kim (2015)
    Working between and beyond the interdisciplinary areas of childhood studies and children’s geographies, this thesis explores how children learn practices of everyday mobility in metropolitan Helsinki (population 1.4 million). Children’s urban movement has become a contested issue in Euro-American settings due to a range of developments, among them the growth in car traffic, the increase in travel distances to school and the widening influence of risk thinking on cultural understandings of childhood. Such tendencies have conspired to intensify the regulation of children’s engagements with urban environments, thereby circumscribing their agencies and sociabilities. Elaborating a more affirmative account of children’s mobility, this thesis gives prominence to the varied competencies, experiences and knowledges of movement that are already in place in the daily lives of families. Through a close exploration of the actual practices whereby children foster their mobilities, the thesis indicates that some of the current concerns around children’s urban movement are misplaced and that societies need to reconsider how children are involved in the shaping of present and future mobilities. The thesis draws on empirical research in two specific sites where children in Helsinki learn mobility: a model traffic area for 5-10-year-olds and the school journeys of 7-12-year-olds, the first of these providing an entry-point into formal pedagogical practices, the second into informal learning through mundane urban travel. The study has deployed various qualitative and participatory methods—including mobile ethnography, digital picture-making and visual interviews—to create an open-ended and flexible arena for children, parents and educators to experiment with diverse ways of becoming mobile and to convey their experiences of such becomings. Further extending this approach, the thesis allies itself with Donald Woods Winnicott, Daniel Stern, Gilles Deleuze, Bruno Latour and other thinkers to trace out a series of mobility experiments, transformative relational arrangements, which suggest a three-fold argument about mobile learning. First, the thesis develops a detailed account of children’s mobility that eschews generalised assumptions about their agency, stressing instead its dynamic and relational emergence as part of daily practices of movement. Children’s mobility in Helsinki is often constituted in collective experiments that draw together a variety of people and materials, from parents and siblings to zebra crossings and bicycles—all carefully composed to engage children in an equally safe and playful elaboration of their agency in relation to other urban bodies. Describing these heterogeneous set-ups and their intricate workings, the thesis brings out the creativity and diversity of children’s everyday movements. Second, the thesis proposes an affirmative view of children’s mundane mobilities by demonstrating that the experimental forms of learning cultivated by the families and educators in Helsinki contribute to children’s sense of belonging in urban and traffic environments. Such experimental learning speaks of more caring and collaborative styles of movement that this thesis further clarifies in an attempt to develop alternative ways of understanding children’s mobility that bypass some of the control-oriented and risk-averse attitudes surrounding the geographies of childhood in present Euro-American societies. This also enables a closer examination of how mobility experiments could help academics, educators, planners and other professionals to support and stimulate children’s mobility in a manner that enriches their civic agency and participation. Third, the thesis elaborates a methodological argument about the importance for childhood research to move beyond the effort to describe the world as it appears towards a more active and collective experimentation with the ways in which the world could become otherwise, as dealing with ever-complex empirical challenges asks for more dynamic and open-ended modes of working. The thesis indicates that understanding issues such as children’s mobility requires continuous experimentation with concepts, devices and methods so that both researchers and participants have an opportunity to detect and amplify unexplored possibilities in their practices. The areas of childhood studies and children’s geographies, through their interdisciplinary inclinations and sensitivities to human potential and transformation, are particularly well placed to contribute to such an exploration of more responsive forms of engagement.
  • Jyrkiäinen, Senni (2010)
    This is an ethnographic study of the mobility of women in Upper Egypt. It is based on two months of fieldwork conducted in the governorate of Sohag. A central argument of this study is that the critical re-evaluation of spatial divisions is needed to come to grips with the complexity of ways in which space is actually understood. Upper Egypt or the Sa’id is a culturally specific region that is labelled as traditionalist, family-centred and patriarchal. Sa'idi women negotiate mobility in public space within the community with regard to such principles as the avoidance of shame and respect towards familial authorities. Despite the small size of the governorate the ideas and practices related to mobility are diverse. The aim of this study is to ethnographically illustrate the heterogeneity that is linked with spatial constructions. Using the theory of practice, I show that women, as active mobile agents, construct, negotiate, regulate, and finally give social meanings to space. By means of participant observation and interviews I study two socially distinguishable groups. I concentrate on highly-educated middle class women living in urban surroundings. As a reference point, I have a group of rural non-educated women. With regard to the two mentioned groups the following themes are studied: how women, as active agents, negotiate their mobility in public space, how the question of women’s mobility is related to the morals of the patriarchally arranged community and how the different social classes regard spatial organisation. Mobility is an embodied activity that is founded on the inseparable relationship between body and space. In feminist anthropology, the theoretical division between male-oriented public and female-oriented private space has evoked a lot of discussion. This study reveals that, not so much the concepts of public and private, but the spatial division between familiar and unfamiliar helps to understand on what basis the mobility of women is regulated and negotiated. Moreover, it is shown that the urban middle class and the rural lower class have very different kinds of spatial practices. The data displays that the ability to regulate privacy and to make spatial divisions requires resources. Finally, the results suggest that there is no single Egyptian understanding of space. Spatial categorisations are renegotiated all the time, as is gender. As commonly shared ideas of womanhood change, spatial practices find new forms. This study is an attempt to understand contemporary spatial practices in the relatively little studied Sa’idi region and to provide a reconsideration of spatial divisions in the light of the ethnographic data.
  • Valros, Niklas Folke Harri (2007)
    Pro gradu -avhandlingens forskningsobjekt är finska mobilkonsumenter i åldern 20–71 år. Syftet med undersökningen är att granska samt kartlägga användningen av nyttiga och nöjaktiga mobiltjänster. Vilka är de populäraste tjänsterna? I bakgrunden fungerar Colin Campbells teori om hedonism i konsumtionssamhället. Även intresset för ny teknologi är ett centralt tema i undersökningen. Med hjälp av teorier från dessa temaområden profileras mobilkonsumenten i nyttokonsumenter respektive nöjeskonsumenter och samtidigt görs en skillnad mellan modern och traditionell hedonism. Med andra ord söks kännetecken för detta slag av konsumtionsbeteende och samtidigt undersöks vilket intresset för nya innovationer och ny teknologi är. Undersökningens material består av ett statistiskt material från år 2003. Materialet härstammar från Konsumtionsforskningscentralen. Materialet är icke-slumpmässigt och behandlar frågor kring användning av mobila tjänster och mobiltelefoner. Inga öppna frågor är inkluderade i undersökningen. Konsumentprofiler har sökts med hjälp av kvantitativa metoder. Materialet är delat i målvariabler och kriterievariabler. Kriterievariablerna är nödvändiga med tanke på konstrueringen av konsumentprofilerna. I avhandlingen uppfattas mobiltjänsterna som relativt ointressanta. Ingen särskild grupp visade sig vara speciellt intresserad av användningen av tjänsterna. Vissa tecken på modern hedonism kunde ändå urskiljas eftersom många hade testat tjänsterna åtminstone en gång och innehavet av nyare mobilmodeller kunde konstateras. Nyttotjänsterna var populärare än nöjestjänsterna. Även om materialet gav goda förutsättningar till en indelning i nytto- och nöjeskonsumtion, visade det sig att dessa två dimensioner inte existerade. Istället handlade det om sk blandkonsumtion, dock med en tyngdpunkt på nyttan. Trots att användningen av mobiltjänster inte är en särskilt bra markör på hedonism kan man dock dra försiktiga slutsatser som baserar sig på innehav av mobilmodeller samt på testandet av tjänsterna. Ju mer avancerad teknologi ägs, desto oftare använder man sig av fördelar den nya teknologin för med sig. Men det handlar inte om traditionell konsumtion, rättare sagt handlar det om modern konsumtion där vikten inte längre ligger på varans praktiskhet eller på ett behov. Snarare handlar det om ett slag av teknologisk nyfikenhet. Konsumtion av mobiltjänster är ett fenomen som inte ännu idag har ett tydligt ansikte.
  • Ollila, Marja-Liisa (1986)
  • Haltia, Heidi (Helsingin yliopisto, 2015)
    Tutkimuksessa pyrittiin selvittämään modaaliverbien käytön kehittymistä oppijansuomessa Eurooppalaisen viitekehyksen taitotasoilla A2-C2. Tutkimuskysymyksiä olivat: (1) Millainen modaaliverbien käyttö on tyypillistä kullekin tutkituista taitotasoista? (2) Miten modaaliverbien käyttö kehittyy Eurooppalaisen viitekehyksen tasolta A2 tasolle C2? (3) Mitkä modaaliverbit aiheuttavat suomenoppijoille vaikeuksia ja (4) miten modaaliverbit vaikuttavat suomenoppijoiden viestintäkykyyn? Aineistona käytettiin Oulun yliopiston ICLFI-korpuksesta otettuja tekstejä, joiden kirjoittajat opiskelevat suomea vieraana kielenä ulkomaisissa yliopistoissa. Tutkimuskysymyksiä lähestyttiin kahdella tapaa. Ensinnäkin modaaliverbien käytön kehittymistä tutkittiin DEMfad-mallin mukaisesti frekvenssin, tarkkuuden ja distribuution näkökulmasta. Toiseksi tutkimuksessa pohdittiin kvalitatiivisesti sitä, miten modaaliverbien käyttö vaikuttaa oppijan viestintätaitoihin. Tutkimuksen teoreettisena taustana käytettiin käyttöpohjaisen kieliopin ajatuksia toisen tai vieraan kielen omaksumisesta. Tutkimuksessa huomattiin, että aineiston modaaliverbien käytössä tapahtui kaksi murrosta. Niistä ensimmäinen koski modaaliverbien esiintymäfrekvenssiä ja tapahtui taitotasolta A2 tasolle B siirryttäessä. Tasolla C2 modaaliverbien esiintymäfrekvenssi laski jälleen. Toinen murros koski modaaliverbien tarkkuuden ja distribuution kehitystä ja tapahtui taitotasolla C tultaessa. Tällöin modaaliverbien käyttö muuttui keskeisimpien modaaliverbien osalta kohdekieliseksi sekä varioivaksi. Modaaliverbien käytön variaatio ja tarkkuus olivat verrannollisia taitotason kanssa: mitä ylempää taitotasoa kirjoittaja edusti, sitä varioivampaa ja tarkempaa modaaliverbien käyttö keskimäärin oli. Vastaavaa korrelaatiota ei havaittu esiintymäfrekvenssin ja taitotason välillä. Tutkimuksen perusteella mahdollisuutta ilmaisevien modaaliverbien käyttö aiheuttaa suomenoppijoille enemmän vaikeuksia kuin välttämättömyyttä ilmaisevien. Yleisimpiä ongelmia olivat eri modaaliverbien välisen työnjaon selkeytymättömyys sekä modaaliverbien käyttö kohdekielelle epätyypillisissä konteksteissa. Tutkimus antoi viitteitä sen suuntaan, että ainakin oppijan äidinkielen siirtovaikutus ja tuotettava tekstilaji vaikuttaisivat modaaliverbien käyttöön. Tutkimustulokset poikkesivat modaaliverbien oppimisjärjestyksen puolesta eräistä muista suomea toisena kielenä opiskelevien modaaliverbien käyttöä sivunneiden tutkimusten tuloksista. Tämä antaa viitteitä sen suuntaan, että myös oppimisympäristöllä olisi vaikutusta käytettyihin modaaliverbeihin. Tutkimuksen perusteella modaaliverbien kohdekielinen käyttö parantaa tekstin sidosteisuutta, tehostaa oppijan kykyä ilmaista mielipiteitään sekä parantaa hänen kykyään tuottaa argumentoivia ja akateemisia tekstilajeja. Näin ollen modaaliverbien hallinta on yhteydessä Eurooppalaisen viitekehyksen eri taitotasoille asettamiin viestinnällisiin tavoitteisiin.
  • Sarmola, Jaakko (2001)
  • Hirvelä, Jaakko (Helsingin yliopisto, 2014)
    This thesis examines the necessary and sufficient conditions of knowledge from the perspective of modal epistemology, and thus attempts to explicate the nature of knowledge. This study aims to answer the question what is knowledge? The main hypothesis is that by excluding those beliefs that are true only in virtue of good epistemic luck outside of knowledge, we might find the necessary and sufficient conditions of knowledge. The structure of the thesis is four folded. The first part defines epistemic luck. After that, two widely discussed modal conditions safety and sensitivity (which aim to define knowledge as essentially as a non-lucky true belief) are evaluated. After critically evaluating both of these conditions and having found them wanting, a novel modal condition is presented which is superior to both safety and sensitivity. The new condition global safety differs from existing modal conditions in terms of what beliefs count as relevant when determining whether a subject has knowledge or not. Global safety is concerned not only about the truth of the belief formed in the actual world, but also about the truth of the beliefs formed in possible worlds. According to global safety a subject has knowledge only if she could not easily have erred. To know is to be safe from error. The condition developed in the study is offered as expressing both the necessary and sufficient conditions of knowledge. The study presents widely contemporary modal epistemology and evaluates different positions critically. The thesis makes also a positive contribution to contemporary discussion and defends a novel view, which the author hopes to be of significance.
  • Kangasniemi, Heikki (1992)
  • Salminen, Marko J (1995)
  • Nordberg, Taneli (Helsingin yliopisto, 2010)
    Tämän pro gradu -lopputyön aiheena on englannin kielen modaalisten apuverbien ns. ydinjoukko: will, would, can, could, shall, should, may, might ja must. Semantiikan kannalta nämä apuverbit ovat erityisen kompleksisia: niiden tulkinnassa on usein huomattavaa monivivahteisuutta, vaikka perinteiset kieliopit antavat ymmärtää niillä olevan kaksi tai kolme toisistaan selkeästi erillään olevaa merkitystä. Ne asettavatkin vieraan kielen oppimisympäristössä erityisiä haasteita. Viimeaikainen kehitys korpuslingvistiikan metodeissa on tuottanut entistä tarkempia kuvauksia siitä, miten modaalisia apuverbejä nykyenglannissa käytetään ja mihin suuntaan niiden kehitys on lyhyenkin ajan sisällä kulkenut. Tämän tutkielman tavoitteena on ollut verrata näiden uusien tutkimusten tuloksia siihen todellisuuteen, jonka englannin kielen lukiotasoinen oppimateriaali Suomessa opiskelijalle tarjoaa. Lähdin siitä, että opetussuunnitelman vaatima autenttisuus ja kommunikaativisuus kieltenopetuksessa tulisi näkyä tasapuolisena modaalisten apuverbien kohteluna. Alkuperäinen hypoteesini kuitenkin oli, että siinä miten modaalisuus ilmenee autenttisessa ympäristössä ja siinä miten se esitetään oppikirjoissa, on poikkeavuuksia. Lähestymistapani tähän tutkielmaan oli korpuslähtöinen. Valitsin kahdesta lukion kirjasarjasta ne kirjat, joissa modaaliset apuverbit mainittiin eksplisiittisesti. Skannasin jokaisen neljästä eri kirjasta löytyvän (kokonaisen) tekstin ja rakensin näistä aineksista pienen korpuksen. Tästä korpuksesta hain korpusanalyyseihin tarkoitetulla ohjelmalla kaikki lauseet, joissa esiintyi modaalisia apuverbejä. Tämän jälkeen analysoin jokaisen modaalisen apuverbin semanttisesti lauseyhteydessään. Tämän analyysin tuloksena pystyin rakentamaan taulukoita ja vertailemaan tuloksia uusimpien tutkimusten tuloksiin. Tämän tutkielman perusteella poikkeavuuksia on olemassa. Yleisesti ottaen modaalisten apuverbien keskinäinen frekvenssi oli oikean suuntainen: mitään apuverbiä ei ollut käytetty merkittävästi enemmän tai vähemmän kuin mitä viimeaikaisen tutkimuksen valossa olisi suotavaa. Sen sijaan apuverbien semanttisessa jakaumassa oli paikoin suuriakin eroja siinä, mitkä merkitykset oppikirjoissa painottuivat ja mitkä taas nykyenglannissa vaikuttaisivat olevan frekvensseiltään suurempia. Erityisesti can ja must erottuivat joukosta siinä, että oppikirjojen tarjoama kuva niiden käytöstä on päinvastainen kuin mitä voisi odottaa: can-verbin käyttö painottui selvästi tarkoittamaan ’kykyä’ eikä ’mahdollisuutta’, joka nykytutkimuksen valossa on sen pääasiallinen käyttötapa. Toisaalta must tarkoitti aineistossa ylikorostuneesti ’pakkoa’, kun se useimmiten nykyään tarkoittaa yhtä usein ’johtopäätöstä’ kuin ’pakkoa’. Lisäksi ’lupaa’ pyydettiin aineistossa merkillisen harvoin. Tulosten perusteella esitän, että oppikirjojen tekijät yleisellä tasolla luopuisivat kielioppikirjojen luutuneista käsityksistä ja uskaltaisivat altistaa opiskelijat koko modaalisten apuverbien merkityskirjolle.
  • Moltchanova, Elena (2000)
    Bacterial meningitis (inflammation of brain lining) caused by Neisseria meningitidis (meningococcus) may be life-threatening, meningococcus of serogroup B being the predominant agent of disease in industrialized countries. Natural immunity against disease develops with age associated with an increase in serum bactericidal activity. Although bacterial MenB meningitis is relatively rare, its severity and possible sequelae necessitate search for efficient vaccine. Since human clinical trials are costly and are often limited by ethical considerations there is a need for animal model, in which disease development and protection would depend on the same mechanism as in humans. This experiment is part of the study to access the relevance of infant rat animal model. The experiment was randomised at two levels: human volunteers were randomly assigned Norwegian, Cuban, or placebo vaccines and outbred rat pups were randomly assigned into 6-rat groups. Each day of the trial 1 group was injected with saline solution and 1-3 groups were injected with heated human serum samples taken before and after the vaccination with interval of 6 month. Thus two sources of random variation must to be taken into account: the human sera variation and variation between rat pups. It is often the case in dose response studies, that the observed effect is a combination of latent natural and treatment responses, where the treatment effect is of interest. A common way to model a binary situation is Abbott's formula. It can be extended to account for a situation with ordinal response. The treatment effect was assigned proportional odds model with strain and treatment covariates, and a full Bayesian model with vague priors was set-up. Two outcomes were examined: the proportion of protected rats (binary) and proportional reduction of bacteremia (ordinal). Both models were estimated using programme WinBUGS12beta. Large variability was apparent both between human sera and between individual rats. Probability of natural response occurrence was high in both models, but no significant treatment effects was found. In order to access the relevancy of this infant rat model to human sera protective immunity, the results of this experiment should be compared with the results of human clinical trials.
  • Zhang, Qiongchao (2013)
    With the global changes in supply and demand for forest products and their international trade, analyzing the long-term development of the Finnish stumpage market and forecasting different assortments of Finnish stumpage prices is more and more important. There are limited number of studies on forecasting Finnish stumpage prices and even less up to date information about forecasting the markets. According to the previous studies, it is difficult to get precise forecasting results in real-life situations, purely utilizing simple time-series forecasting methods. In addition, the forecasting error is usually unavoidable in the price forecasting studies. The present study increases information on stumpage price forecasting using updated price data and testing alternative statistical approaches that take account of structural changes of stumpage prices in Finnish roundwood market. The aims of this study are to test applicability of alternative statistical approaches in forecasting long-run stumpage price development up to 2050. The annual price data are from the years 1967-2010. First we tested the stationarity of time-series data, using an augmented Dickey-Fuller (ADF) Unit root test. Compared to the complicated prices behaviors of sawlog, the prices behaviors of pulpwood are much more stationary. It can be seen clearly that there are three business cycles both in sawlog and pulpwood prices, around 30 years per cycle. Further studies can be analyzed involving some impact factors to the demand and supply of Finnish roundwood, such as prices of roundwood and forest products export, prices in domestic market, GDP of Finland, etc. Basing on the results of the study, the forecasted prices of all assortments of Finnish roundwood will decline from 2010 to 2023. We assume that the Finnish roundwood market will suffer from the global changes of demand and supply of forest products. Demands for many traditional end products are decreasing in Europe. Thus we recommend the Finnish roundwood market stakeholders should pay more attention on this situation. The forestry companies can change their products structure: develop more new products in bioenergy industry; what is more, companies can develop new markets in internationally. The forest private owners should communicate more frequently with roundwood market experts and forest industry to build a coherent picture on industry trends impacting roundwood price determination.
  • Miettinen, Jarkko (Helsingin yliopisto, 2009)
    This thesis addresses modeling of financial time series, especially stock market returns and daily price ranges. Modeling data of this kind can be approached with so-called multiplicative error models (MEM). These models nest several well known time series models such as GARCH, ACD and CARR models. They are able to capture many well established features of financial time series including volatility clustering and leptokurtosis. In contrast to these phenomena, different kinds of asymmetries have received relatively little attention in the existing literature. In this thesis asymmetries arise from various sources. They are observed in both conditional and unconditional distributions, for variables with non-negative values and for variables that have values on the real line. In the multivariate context asymmetries can be observed in the marginal distributions as well as in the relationships of the variables modeled. New methods for all these cases are proposed. Chapter 2 considers GARCH models and modeling of returns of two stock market indices. The chapter introduces the so-called generalized hyperbolic (GH) GARCH model to account for asymmetries in both conditional and unconditional distribution. In particular, two special cases of the GARCH-GH model which describe the data most accurately are proposed. They are found to improve the fit of the model when compared to symmetric GARCH models. The advantages of accounting for asymmetries are also observed through Value-at-Risk applications. Both theoretical and empirical contributions are provided in Chapter 3 of the thesis. In this chapter the so-called mixture conditional autoregressive range (MCARR) model is introduced, examined and applied to daily price ranges of the Hang Seng Index. The conditions for the strict and weak stationarity of the model as well as an expression for the autocorrelation function are obtained by writing the MCARR model as a first order autoregressive process with random coefficients. The chapter also introduces inverse gamma (IG) distribution to CARR models. The advantages of CARR-IG and MCARR-IG specifications over conventional CARR models are found in the empirical application both in- and out-of-sample. Chapter 4 discusses the simultaneous modeling of absolute returns and daily price ranges. In this part of the thesis a vector multiplicative error model (VMEM) with asymmetric Gumbel copula is found to provide substantial benefits over the existing VMEM models based on elliptical copulas. The proposed specification is able to capture the highly asymmetric dependence of the modeled variables thereby improving the performance of the model considerably. The economic significance of the results obtained is established when the information content of the volatility forecasts derived is examined.
  • Takolander, Antti (2014)
    Climate change has been predicted to cause extinctions and range shifts in European flora. Two common methodologies assessing climate impact on vegetation are statistical bioclimatic envelope models (BEMs) and process-based dynamic vegetation models. BEMs are relatively easy to implement, but have been criticized for being unreliable, because they assume equilibrium between species’ observed ranges and climate. Dynamic models can be considered biologically more sound, but require large quantities of detailed input data, which is often not available. The aim of this study is to investigate the effects of climate change on common tree species ranges in Europe and in Scandinavia, and to find out whether two commonly used modeling strategies, dynamic and statistical models, produce similar estimates of future ranges. To address these questions, I first built statistical models (bioclimatic envelope models) for five common European trees: Pedunculate Oak (Quercus robur, L.), Common Hazel (Corylus avellana L.), European Beech (Fagus sylvatica, L.), Scots Pine (Pinus sylvestris, L.) and Norway Spruce (Picea abies (L.) H. Karst.). All species are widely distributed and characteristic species in their ecosystems and thus their possible range shifts would indicate larger shifts in ecosystem structure and function. I then compare the projections produced with the statistical models to outputs of a tree speciesparameterized dynamic global vegetation model LPJ-GUESS, obtained from another study. The statistical model predictions are compared with dynamic model results for entire European distributions, while the statistical model predictions for Scandinavian area are examined in further detail. Input distribution data had great influence in future predictions of statistical models. Statistical models and the dynamic model produced very different future predictions, statistical models predicting increasing contractions on the southern edge of distribution towards the end of the century, indicating larger climatic impacts. The role of biological interactions, successional processes and modeling relationship between distribution and climate are discussed. I propose a way to assess the possible causes of differences between statistical and dynamic models to produce more robust future predictions on plant species distributions. Statistical model predictions in the Scandinavian area indicated substantial northward shift of hemiboreal vegetation zone by 2050.