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Time-dependent hierarchical data is a complex type of data that is difficult to visualize in a clear manner. It can be found in many real-life situations, for example in customer analysis, but the best practices for visualizing this type of data are not commonly known in business world. This thesis focuses on visualizing changes over time in hierarchical customer data using the Plotly Python Graphing Library and is written as an assignment for a Finnish company. The thesis consists of a literature survey and experimental part. The literature survey introduces the most common hierarchical visualization methods, and the different possible encoding techniques for adding time dimension on top of these hierarchical visualization methods. Moreover, the pros and cons of different visualization techniques and encodings are discussed about. In the experimental part of the thesis, visualization prototypes are designed using the Plotly Python Graphing Library. A company customer data set of the commissioning company is partitioned into hierarchical customer segments by a hierarchical industrial classification TOL 2008, and changes over time in a continuous variable are visualized by these segments. Two hierarchical visualization techniques: the sunburst chart and treemap, are used to create two prototype versions, and the combination of color, typography, and interaction is used to encode time dimension in these prototypes. The same prototypes are also exploited to visualize customer segments by an artificial hierarchy created by combining multiple categorical features into a hierarchical structure. The prototypes are validated in the commissioning company by arranging an end user study and expert review. Concerning the prototypes by the industrial classification: According to the end users and experts, both prototype versions are very useful and well-implemented. Among the end users, there was no significant difference in which one of these prototype versions is faster to use, but the clear majority of the respondents regarded the sunburst chart version as their favorite prototype. The two experts who participated in the expert review had different opinions on which one of the prototype versions they would select to be utilized in practice. Concerning the prototypes by the artificial hierarchy: These prototypes also received positive feedback, but the possibility to change the order of features in the hierarchy was considered as an extremely important development idea. ACM Computing Classification System (CCS): Human-Centered Computing → Visualization → Visualization Techniques Human-Centered Computing → Visualization → Empirical Studies in Visualization

A population is said to be genetically structured when it can be divided into subpopulations based on genetic differences between the individuals. As in case of Finland for example, the population has been shown to consist of genetic subpopulations that correspond strongly to geographical subgroups. Such information may be interesting when seeking answers to questions related to the settlement and migration history of some population. Information about genetic population structure is also required for example in studies looking for associations between genetic variants and some inheritable disease to ensure that the groups with and without diagnosis of the disease resemble each other genetically except for the genetic variants causing the disease. In my thesis, I have compared how two different mathematical models, principal component analysis (PCA) and generative topographic mapping (GTM), visualize ancestry and identify genetic structure in Finnish population. PCA was introduced already in 1901, and nowadays it is a standard tool in identifying genetic structure and visualizing ancestry. GTM instead was published relatively recently, in 1998, and has not yet been applied in population structure studies as widely than PCA. Both PCA and GTM transform high-dimensional data to a low-dimensional, interpretable representation where relationships between observations of the data are summarized. In case of data containing genetic heterogeneity between individuals, this representation gives a visual approximation of the genetic structure of the population. However, Hèlèna A. Gaspar and Gerome Breen found in 2018 that GTM is able to classify ancestry of populations from around the world more accurately than PCA: the differences recognized by PCA were mainly between geographically most distant populations, while GTM detected also more their subpopulations. My aims in the thesis were to examine whether applying the methods for Finnish data would give similar results, and to give thorough presentations of the mathematical background for both the methods. I also discuss how the results fit into what is currently known about the genetic population structure in Finland. The study results are based on data from the FINRISK Study Survey collected by the National Institute for Health and Welfare (THL) in 1992-2012 and include 35 499 samples. After performing quality control on the data, I analysed the data with SmartPCA program and ugtm Python package implementing PCA and GTM, respectively. The final results have been presented for such 2010 individuals that participated the FINRISK Study Survey in 1997 and whose both parents were born close to each other. I have assigned the individuals into distinct geographical subgroups according to the birthplaces of their mothers to find out whether PCA and GTM identify individuals having a similar geographical origin to be genetically close to each other. Based on the results, the genetic structure in Finland is clearly geographically clustered, which fits into what is known from earlier studies. The results were also similar to those observed by Gaspar and Breen: Both the methods identified the genetic substructure but GTM was able to recognize more subtle differences in ancestry between the geographically defined subgroups than PCA. For example, GTM discovered the group corresponding to the region of Northern Ostrobothnia to consist of four smaller separate subgroups, while PCA interpreted the individuals with a Northern Ostrobothnian origin to be genetically rather homogeneous. Locating these individuals on the map of Finland according to the birthplaces of their mothers reveals that they also make four geographical clusters corresponding to the genetic subpopulations detected by GTM. As a final conclusion I state that GTM is a noteworthy alternative to PCA for studying genetic population structure, especially when it comes to identifying substructures from a population that PCA may interpret to be genetically homogeneous. I also note that the reason why GTM generally seems to be capable of more fine-grained clustering than PCA, is probably that PCA as a linear model may cause more bias to the results than GTM which accounts for also non-linear relationships when transforming the data into a more interpretable form.

This thesis investigates the problem of Visual Simultaneous Localization and Mapping (vSLAM) in changing environments. The vSLAM problem is to sequentially estimate the pose of a device with mounted cameras in a map generated based on images taken with those cameras. vSLAM algorithms face two main challenges in changing environments: moving objects and temporal appearance changes. Moving objects cause problems in pose estimation if they are mistaken for static objects. Moving objects also cause problems for loop closure detection (LCD), which is the problem of detecting whether a previously visited place has been revisited. A same moving object observed in two different places may cause false loop closures to be detected. Temporal appearance changes such as those brought about by time of day or weather changes cause long-term data association errors for LCD. These cause difficulties in recognizing previously visited places after they have undergone appearance changes. Focus is placed on LCD, which turns out to be the part of vSLAM that changing environment affects the most. In addition, several techniques and algorithms for Visual Place Recognition (VPR) in challenging conditions that could be used in the context of LCD are surveyed and the performance of two state-of-the-art modern VPR algorithms in changing environments is assessed in an experiment in order to measure their applicability for LCD. The most severe performance degrading appearance changes are found to be those caused by change in season and illumination. Several algorithms and techniques that perform well in loop closure related tasks in specific environmental conditions are identified as a result of the survey. Finally, a limited experiment on the Nordland dataset implies that the tested VPR algorithms are usable as is or can be modified for use in long-term LCD. As a part of the experiment, a new simple neighborhood consistency check was also developed, evaluated, and found to be effective at reducing false positives output by the tested VPR algorithms.

The topic of the thesis is shared housing, in which the apartment is shared voluntarily by people that are not all family members. Shared housing is often associated with young people and students and is thus seen as a temporary form of housing. Indicative statistics, social and traditional media, and corporate behavior provide indications of an increase in the popularity or attractiveness of shared housing. This thesis sheds light on shared housing as a phenomenon and brings it into the discussion around community housing and housing diversity. In the thesis, I focus on shared housing (1) as a personal experience of home and (2) as a form of housing outside the normative ideal home. Earlier research on shared housing has suggested it is related to economic realities, as housing is becoming more expensive in big cities, but at the same time social norms related to housing are changing (Heath et al. 2018; Maalsen 2019). In addition to economic reasons, living with other people is a major reason for choosing shared housing and the success of it depends to a large extent on the social relations inside the home (Heath et al. 2018). The thesis is based on critical geography of home. In humanistic geography home has been understood as an ideal and fundamental place connected to feelings of security and belonging. However, home can also be a place of negative emotions, and critical geography of home (Blunt & Dowling 2006) understands home as a broader concept and as an originator and maintainer of normative structures. A home is not only a material place, but also an imaginary. It is also political and multi-scalar. The research was carried out following the ethnographic research tradition. It took place in three research homes in the Helsinki metropolitan area. The methods used were thematic interviews, some of which were group interviews, and participatory observation. In the analysis of the data, I aim for consistency and transparency. The analysis focuses on four themes: 1. The role of the physical characteristics of the dwelling, 2. The role of social relationships, 3. Economic reasons and sharing of goods, 4. Normative assumptions and prejudices. Based on this research, a shared house or flat can feel like home. The physical characteristics of the dwelling as well as the presence of other people create the feeling of home. The reasons for choosing shared housing are complex, but affordability and the desire to live with others are both recognized as driving forces. The prejudices associated with shared housing have partly diminished, but it is still connected to young people. Normative perceptions of home and housing became visible during the study and the family was connected to home. The presence of flat mates can bring family-like feelings of security and caring, as well as everyday social interactions to home. Shared housing can enable higher quality housing at a lower cost, but the functioning of interpersonal relationships is essential for the success of shared housing.

Volatiliteetin käsite on keskeisessä roolissa optioiden hinnoittelun teoriassa, ja reaalimaailman op- tiopositioilla realisoituva volatiliteetti on merkittävä tuloksen ajuri. Yksinkertaisilla optiopositioilla on kuitenkin vaikeaa saada aikaiseksi sellainen sijoitussalkku, joka ainoastaan riippuisi toteutuvasta volatiliteetista. Toteutuvaan volatiliteettiin liittyen voidaan kuitenkin sopia varianssin vaihtosopi- muksesta, jossa osapuolet vaihtavat keskenään kiinteän varianssin hinnan ja toteutuvan varianssin erotuksesta johdettua kassavirtaa. Tässä tutkielmassa varianssin vaihtosopimuksille johdetaan markkinaehtoinen hintakaava staat- tisen toistamisen ja synteettisen logaritmisopimuksen avulla. Tämä varianssin vaihtosopimuksen markkinahinta osoittautuu riippuvan kaikista markkinoilla kaupankäynnin kohteena olevista optioista ja erityisesti näiden volatiliteettihymystä. Erilaisten osakepolun neliövariaatiosta riippuvien kaupankäyntistrategioiden analysointia varten sovelletaan erästä stokastisen volatiliteetin mallia toteutuvan tuloksen simuloimiseen. Osoittautuu, että varianssin vaihtosopimus tarjoaa merkittävästi erilaisen sijoitusinstrumentin, jonka varallisuus kehittyy usein hyvin eri tavalla kuin osake, jonka toteutuvalla varianssilla on käyty kauppaa.

Climate change is increasingly bringing new environmental and climate-related challenges, which all will notably affect the agriculture sector. Geographers have addressed the topic traditionally from the environmental perspective, but more recently, the focus has also been on the social outcomes of climate change. One of the central topics in the climate change research continues to be the analysis of the level of vulnerability to climate change. Despite its central position, the concept of vulnerability has remained vague and undefined. Most often it includes the elements of exposure, sensitivity and adaptive capacity, and they form the core of the vulnerability analysis both for Geography and for other fields of research. Common outcome of the vulnerability analysis is an index, which can be used for measuring vulnerability level in a certain context, e.g. in the agriculture sector, as in this research context. The main focus is often on two former elements, exposure and sensitivity, which means that the socio-economic context is left for a lesser examination, even though it holds aspects that can determine individual’s possibility to cope and adapt with the changing environmental condition and therefore form the base for their level of vulnerability. Rather than examining the elements of exposure and sensitivity, this research focuses on adaptive capacity through the concept of contextual vulnerability. The analysis concentrates mainly on the elements of social and human capital arguing that these elements should have a stronger position when performing the vulnerability analysis that aims to strengthen adaptation. This research examines the concept of vulnerability to climate change on two different levels: first on the concrete level, which builds on the experiences of smallholder farmers’ perceived vulnerability, and secondly, on the discursive level, which focuses on the gendered narratives and power structures within the concept. Despite the distinction, these levels are highly linked through climate change and agriculture policies and decision-making. This research criticises the prevailing ‘vulnerable women’ narrative of the vulnerability discourse by examining smallholder farmers’ adaptation strategies in order to see whether there are in fact some gendered differences, as it is often underlined in the global discourses. This research builds on the post-structural methodology and examines the topic through a case-study in Taita Hills, Kenya. The key methods of the research are a semi-structured interview and a critical discourse analysis. The collected data consists of the two-headed household interviews with both female and male farmers, the single-headed household interviews with female farmers, and the key informant interviews with different stakeholders from the agriculture sector. The inclusion of both female and male farmers’ perspectives from each household was noted central for performing the gender analysis of the results. The empirical part of this research forms the base for understanding what adaptation and coping strategies farmers are applying, whether the reason for applying these strategies can be explained with the contextual vulnerability concept and how well the results reflect the wider vulnerability discourse. According to this study it is possible to argue that the elements of contextual vulnerability combined with the information regarding individuals’ access to resources can form the baseline for understanding individuals’ possibilities to adapt to changing environmental and climatic conditions. Outcome vulnerability analysis offers highly relevant information, but it is not alone enough for understanding the challenges and possibilities of climate change adaptation. Female and male farmers’ coping and adaptation response strategies did not differ notable, which supports the criticism of the gendered nature of vulnerability discourse. The vulnerable women narrative does not reflect female farmers’ agency and centrality in the agriculture sector. The discourse should be corrected towards addressing structural challenges that can place people to vulnerable position rather than enforcing the gendered narrative of the vulnerable women, whose adaptation and coping strategies are left for lesser attention.

Opetushallitus on laatinut uudet opetussuunnitelman perusteet lukiokoulutukseen vuonna 2019, ja ne otetaan käyttöön elokuussa 2021. Tämän pro gradu -työn tarkoituksena on tutkia uudistuksia matematiikan oppiaineessa vuonna 2019 julkaistuissa opetussuunnitelman perusteissa verrattuina vuoden 2015 opetussuunnitelman perusteisiin. Tämän lisäksi työssä selvitetään, miten vuoden 2015 opetussuunnitelman perusteiden mukaiset oppimateriaalit soveltuvat vuoden 2019 perusteissa olevien uudistusten opetukseen. Tarkasteltava oppimateriaali rajataan tässä työssä kolmen kustantamon lukion matematiikan oppikirjoihin. Oppikirjasarjat, joista tässä työssä etsitään materiaalia, ovat Sanoma Prolta Tekijä, Editalta Summa ja Otavalta Huippu sekä Juuri. Lisäksi yhteisen MAY1-kurssin oppikirjat ovat tarkastelussa kaikilta kolmelta kustantamolta. Tutkimuskysymykset ovat: mitä uudistuksia vuoden 2019 opetussuunnitelman perusteissa on matematiikan sisältöjen osalta verrattuna vuoden 2015 opetussuunnitelman perusteisiin, sekä miten vuoden 2015 opetussuunnitelman perusteiden mukaisiksi laaditut materiaalit soveltuvat uusien sisältöjen opettamiseen. Tutkielman ensimmäisen luvun johdannon jälkeen toisessa luvussa taustoitetaan tutkielman aihepiiriä tutustumalla opetussuunnitelman perusteisiin sekä esittelemällä työssä tarkasteltavat oppimateriaalit. Kolmas luku esittelee tutkielman tutkimuskysymykset, ja tutkimuksen toteutus käydään läpi neljännessä luvussa. Viidennessä luvussa analysoidaan työn tulokset. Tutkielman viimeinen luku on yhteenveto pro gradu -työn keskeisimmistä sisällöistä. MAY1-kurssin ja matematiikan pitkän oppimäärän uusia sisältöjä ovat potenssifunktiot, joissa eksponenttina on positiivinen kokonaisluku, ensimmäisen asteen yhtälön ratkaisu, suorien yhdensuuntaisuus ja kohtisuoruus, käyrän yhtälö, matemaattisten mallien rajoitukset, ristitulo, vuokaavio, yksinkertaisten algoritmien ohjelmointi, paloittain määritelty funktio, koronkorko, nykyarvo, diskonttaus, talletukset, resurssien riittävyys ja kannattavuuslaskenta. Lyhyen oppimäärän uudet sisällöt ovat lineaarisen ja eksponentiaalisen kasvun mallit taulukkolaskentaohjelmaa käyttäen, virhemarginaali ja sen määrittäminen ohjelmistolla, valuutat, korkokäsite ja yksinkertainen korko, koronkorko, diskonttaus ja talletukset. Vuokaaviosta ja ristitulosta ei löytynyt lainkaan materiaalia tarkastelluista oppikirjoista. Kaikkiin muihin uusiin sisältöihin on oppimateriaalia ainakin osassa tarkastelluista kirjasarjoista.

Social and urban scholars have long been concerned with questions of how unknown others encounter and relate to one another in the city. Stranger encounters can happen spontaneously and serendipitously, for example, at bus stops, in trains or on park benches, often viewed as “chance” encounters. Other stranger encounters are carefully planned, for example, by using digital technology including online social networks, websites, and digital platforms. Today, digital platforms are reshaping the way we relate with strangers, yet there is little research on how stranger encounters are reconfigured by practices mediated through digital platforms. Against this background, the thesis attempts to address this research gap: stranger encounters mediated by two location-based digital platforms for social networking in Helsinki. The thesis focuses on two Finnish digital platforms for social networking, Nappi Naapuri and Commu, which are based around neighbourhood and community interactions. Both platforms lower the threshold of communication between strangers which have the potential to help eliminate loneliness, stress, and promote a sense of community. The thesis analyses planned encounters when meeting with other platform users to better understand what types of stranger encounters are emerging from digital platforms. Rather than focusing on the figure of the stranger as ‘other,’ the thesis examines digitally mediated practices whereby stranger encounters are valued and actively pursued by platform users. Through fieldwork encounters with strangers in Helsinki, the thesis analyses six stranger encounter vignettes to argue that by practicing an open and generous attitude towards unknown others can allow for moments of sociable curiosity, escapism, and intimacy to emerge between strangers. Using multiple methodologies including, autoethnography, walking with participants, participant observation and interviews, the thesis aims to better understand the role digital platforms can play in increasing stranger encounters in the city and how they have the potential to bring different people together to learn from one another and work on manners of cohabitation.

Water-ethanol mixtures are commonly used in industry and house holds. However, quite surprisingly their molecular-level structure is still not completely understood. In particular, there is evidence that the local intermolecular geometries depend significantly on the concentration. The aim of this study was to gain information on the molecular-level structures of water-ethanol mixtures by two computational methods. The methods are classical molecular dynamics (MD), where the movement of molecules can be studied, and x-ray Compton scattering, in which the scattering cross section is sensitive to the electron momentum density. Firstly, the water-ethanol mixtures were studied with MD simulations, with the mixture concentration ranging from 0 to 100%. For the simulations well-established force fields were used for the water and ethanol molecules (TIP4P and OPLS-AA, respectively). Moreover, two models were used for ethanol, rigid and non-rigid. In the rigid model the intramolecular bond lengths are fixed, whereas in the non-rigid model the lengths are determined by harmonic potentials. Secondly, mixtures with three different concentrations employing both ethanol models were studied by calculating the experimentally observable x-ray quantity, the Compton profile. In the MD simulations a slight underestimation in the density was observed as compared to experiment. Furthermore, a positive excess of hydrogen bonding with water molecules and a negative one with ethanol was quantified. Also, the mixture was found more structured when the ethanol concentration was higher. Negligible differences in the results were found between the two ethanol models. In contrast, in the Compton scattering results a notable difference between the ethanol models was observed. For the rigid model the Compton profiles were similar for all the concentrations, but for the non-rigid model they were distinct. This leads to two possibilities of how the mixing occurs. Either the mixing is similar in all concentrations (as suggested by the rigid model) or the mixing changes for different concentrations (as suggested by the non-rigid model). Either way, this study shows that the choice of the force field is essential in the microscopic structure formation in the MD simulations. When the sources of uncertainty in the calculated Compton profiles were analyzed, it was found that more statistics needs to be collected to reduce the statistical uncertainty in the final results. The obtained Compton scattering results can be considered somewhat preliminary, but clearly indicative of the behaviour of the water-ethanol mixtures when the force field is modified. The next step is to collect more statistics and compare the results with experimental data to decide which ethanol model describes the mixture better. This way, valuable information on the microscopic structure of water-ethanol mixtures can be found. In addition, information on the force fields in the MD simulations and on the ability of the MD simulations to reproduce the microscopic structure of binary liquids is obtained.

Antarctic Bottom Water (AABW), a water mass that sinks to form the deepest limb of the meridional overturning circulation (MOC), is a key control on the ventilation of the Southern Ocean as well as global exchanges of heat, freshwater, and carbon. Sources of this water mass include latent heat polynyas found in Prydz Bay, East Antarctica, which expose the Southern Ocean to the colder atmosphere and are important sources of high salinity shelf water (HSSW). This water mass is the precursor to Dense Shelf Water (DSW) which can be exported from the continental shelf to form Antarctic Bottom Water (AABW). In this study, Lagrangian particle tracking of water masses within Prydz Bay was used to investigate the roles of seasonality, bathymetry, and the presence of other water masses on the mechanisms of water mass transformation (WMT), a series of key processes in the MOC. Online particles were released weekly within the Prydz Bay polynya region in a 10 km resolution simulation of the Whole Antarctic Ocean Model (WAOM10) and their forward trajectories were tracked for one year. Results highlight the export of Prydz Bay water along the westward Antarctic Slope Current (ASC). Cluster analysis of the results shows a winter signal for bottom water forming particles. When advected beneath the ice shelf, polynya water can mix with fresh meltwater, becoming less dense and forming ice shelf water (ISW). After this polynya-originating water departs the ice shelf again, its increased buoyancy can make future AABW formation less likely. This study confirms that the presence of modified circumpolar deep water (mCDW) can play a controlling factor in rates of DSW export as bottom water. Results show export of DSW from the Prydz Channel and Cape Darnley, mixing either along or across isopycnals depending on the influence of other water masses and cross-slope flow. Interactions with the ASC and major topographic features including the Enderby Land projection and several underwater canyons appear to influence the export of water to the deep ocean. WAOM10 finds realistic ratios of AABW formation as compared with observational data and shows greater low-density water formation than other models.