These days, it is hard to discuss innovation and the creative economy without mentioning platforms, which have become core strategy for dominating the market. An accurate understanding of platform business is a key factor in being a successful platform provider, so discussions of platform strategies need to be invigorated, value chains need to be analysed, and theoretical factors need to be seriously considered. Corporations are yearning for new innovations and worry about the absence of an efficient and sustainable growth model. First, this thesis analyses how the value chain and value stream are changed in the platform business model in order to explore value chains and value streams in the two-sided market, which has a distinct group of users on both sides. It proposes three types of platform business strategy which will serve as a frame of reference for analysing the impact of the different value chains on platform businesses. Second, this thesis indicates how a step-by-step business strategy based on the perspective of dynamic approach could be constructed. This research identifies four major stages of platform business (entry stage, growth stage, expansion stage, and maturity stage), and different core elements and strategies exist for each stage. These serve as the conceptual frameworks with which to build a platform business model. The key contributions of this research are as follows. Firstly, the main differences and features of the literature reviewed were suggested with collective action and strategic choice perspectives from different academic approaches. Secondly, this study extends the understanding of the value chain that was the critical strategic element of a corporation in the platform business. Thirdly, this research presents the core elements and strategies for each of the four major growth stages of platform business with the dynamic approach, depending on the distinctive features of the contents and platforms.

The design and operation of a two-sided platform require a variety of decisions to facilitate a match between sellers (capacity) and buyers (demand). Many platforms deploy analytic capabilities to leverage rich information, on both demand and capacity, that is available in real-time. This dissertation research explores design decisions, such as price structure and quality controls, and allied analytic capabilities in order to document their impact on platform governance. These decisions are tested in the context of ride-sharing platform by positing three fundamental challenges that must be accounted for effective design: (1) spatial distribution of capacity and demand that allows for capacity spillovers, (2) buyer’s sentiment biases, and (3) seller’s relocation biases. These challenges are assessed in three separate but related essays. The first essay investigates how the policies for setting surge prices should be designed under capacity spillovers. Using a data set from Uber’s operations, we estimate a spatial panel model to reveal its surge pricing structure that accounts for spatial dependency. Allied counterfactual analysis illustrates the limitations of a spot pricing policy (i.e., a policy that does not account for spillovers). The second essay assesses the impact of buyer’s sentiment bias, ranging from optimism to pessimism, on the platform’s decision to control seller quality. Platforms face a trade-off between ensuring high-quality sellers and guaranteeing enough sellers such that wait-time is lowered. We formally characterize an optimal exclusion threshold on seller quality in the presence of sentiment bias. We also examine strategies that a platform can access to benefit from buyer’s behavioral biases. Results document the impact of seller quality on a platform’s profitability and social welfare. In the last essay, we focus on the seller’s relocation behavior. There is a debate in the literature on whether sellers’ willingness to relocate across demand zones in order to chase surging prices is rewarded in a ride-sharing platform setting. Using multiple machine learning algorithms, we classify rewarding behaviors with different pricing structures under a variety of circumstances. Results provide guidance on how to provide incentives while managing the dynamics of spatially distributed capacity.

Platforms are the critical players driving the digital economy. My thesis focuses on the platform economy, especially the competitive advantage of platforms. On the one hand, what factors affect the competitive advantage of platforms? How does the platform form the competitive advantage? These questions are related to platform strategy. On the other hand, does the competitive advantage of platforms harm social welfare? This question is related to regulatory issues. The first chapter of my dissertation studies how different aspects of user effects drive value in two-sided markets. We first develop a model of inter-temporal network effects and within-period network effects of users to estimate different aspects of user effects. We then propose a model to estimate the user lifetime value in two-sided markets and examine the effectiveness of the user growth strategy. Finally, we discuss platform heterogeneity and corresponding platform strategies. Using Groupon data, we empirically estimate different aspects of user effects and examine how they vary. We show that the strength of the inter-temporal same-side network effect affects user stickiness, further influencing the persistence of the within-period cross-side network effect. Strong within-period cross-side network effects alone cannot sustain value creation. Our findings remind managers not to overemphasize user growth when the inter-temporal network effects are weak and should instead focus on platform design that increases user stickiness. The second chapter of my dissertation examines the impact of a potential policy of opening a platform's big data to banks on FinTech lending. We show that the policy promotes competition in FinTech lending and the loan price decreases. However, its impact on financial inclusion is unclear. We discuss how the efficiency of the banking system and the value of big data affect the policy outcome. We also consider the equilibrium of a data market where the platform can sell big data to banks. We show that FinTech can best promote financial inclusion in this case, but the loan price is the same as when the platform monopolizes big data. Since financial inclusion is important for entrepreneurship and innovation, the regulator should carefully examine the context in their countries before making a policy choice. The third chapter of my dissertation studies the impact of cross-market acquisitions of giant platforms on start-ups' entry into emerging markets. Our model shows that the acquisition reduces the post-acquisition entry but may increase the pre-acquisition entry. The net effect of the acquisition on the entry is positive when the pre-acquisition gain is greater than the post-acquisition loss. We then discuss three cases in which a giant platform strategically increases its market position in the acquisition. The net effect of the acquisition on start-ups' entry varies in different cases. Our findings indicate that regulators should analyze the specific situation of each acquisition before making a decision to approve an acquisition.

Yes / Polygon, subdivision, and NURBS are three mainstream modeling techniques widely applied in commercial software packages. They require heavy manual operations, and involve a lot of design variables leading to big data, high storage costs and slow network transmissions. In this paper, we integrate the strengths of boundary-based surface creation and partial differential equation (PDE)-based geometric modeling to obtain the first analytical C continuous 4-sided PDE patches involving sculpting force-based shape creation and manipulation and use them to develop an interactive modeling technique for easy and quick creation of 3D models with small data from vertex-frames. With this modeling technique, a vertex frame is defined by eight vertices, and a C continuous 4-sided PDE patch is created from the vertex-frame through an analytical solution to a vector-valued second-order PDE subjected to the boundary conditions determined by the eight vertices of a vertex-frame. A user-friendly interface is developed from the obtained analytical solution, which enables users to interactively input and modify vertex-frame models easily and create 3D models in real time. Different surface modeling tasks are carried out to test the developed interactive tool and compare our proposed method with polygon and NURBS modeling and Coons surfaces. The results demonstrate the effectiveness of our proposed method and its advantages in reducing design variables, saving storage costs, and effective shape creation and manipulation. / European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 778035; MCIN/ AEI /10.13039/501100011033/ FEDER “Una manera de hacer Europa”

Natural ventilation is an effective method to save energy required to condition buildings and to improve indoor air quality. Computational fluid dynamics (CFD) was used to model single-sided buoyancy-driven natural ventilation in a single room with a heater and door. The velocity and temperature profiles at the doorway agreed fairly well with published literature that includes Mahajan's experimental [2] and Schaelin et al's numerical studies [1]. The 2D and 3D models predicted the neutral level with a difference of 5.6 % and 0.08 % compared to the experimental results, respectively. Using solutions at the doorway, heat transfer rates were calculated. More realistic situations were studied considering conduction, various ambient conditions, wind speeds, and additional heat sources and furniture in the room. The heat loss through the wall was modeled and the airflow and temperature within the room showed no significant changes despite modeling conduction through the walls. Various ambient temperatures and wind speeds were tested, and the neutral level height and total heat transfer rate through the doorway increased with decreasing ambient temperatures. However, the neutral level did not significantly change as wind speeds varied. Total heat transfer rate at the doorway became positive, that is heat transferred into the room, with wind speed. Lastly, the effect of additional heat sources (mini-refrigerator, monitor and computer) and furniture (bookshelf, desk, chair and box) on airflow and heat transfer in the room was analyzed by comparing with a simple case of a room with a heater. Large velocities and high temperatures were predicted in the vicinity of the heat sources. However, the spatially averaged velocity and temperature did not change significantly despite additional heat sources. The room with furniture was modeled at lower ambient temperature, where the spatially averaged velocities were larger and temperatures were lower than the simple case. The room heated up and reached its thermal comfort level, but the velocities exceeded the maximum acceptable level set by ASHRAE guidelines [8]. Wind was considered simultaneously with the lower temperature, and the room was cooled faster with wind. However, the room was never able to achieve the comfortable level both in velocity and temperature. / Master of Science

Many animals exhibit seasonal changes in life-history stages, and these seasonal transitions are often accompanied by dramatic switches in behavior. While the neuroendocrine mechanisms that regulate such behavioral transitions are poorly understood, arginine vasotocin (AVT) and neuropeptide Y (NPY) are excellent candidates because they regulate reproductive and feeding behavior, respectively. In this study, I asked if seasonal changes in AVT and/or NPY are concomitant with spring migration away from the breeding grounds, as male and female red-sided garter snakes (Thamnophis sirtalis parietalis) are transitioning from reproductive to non-reproductive behavior during this time. To address this question, I collected male and female snakes in different migratory stages during the spring and fall. Brains were processed for AVT and NPY immunohistochemistry and the total number of immunoreactive (-ir) cells quantified for each individual. As predicted, males had significantly more AVT-ir cells in the preoptic area and bed nucleus of the stria terminalis, brain regions important for courtship behavior, during the spring mating season compared to the fall. Females had significantly more AVT-ir cells in the preoptic area during the spring compared to the fall and, surprisingly, did not exhibit seasonal changes in NPY. In contrast, males had significantly more NPY-ir cells in the cortex, a region important for spatial memory, and in the posterior hypothalamus during the fall compared to the spring, which likely reflects increased feeding behavior during the summer foraging period. Neither AVT- nor NPY-ir cell number varied significantly with migratory status, indicating that seasonal changes in these neuropeptides are not directly related to migration. I then asked if the observed seasonal changes in AVT and NPY in males and females are related to the transition from reproductive to non-reproductive states. Compared to courting males, non-courting males had significantly more AVT-ir cells in the supraoptic nucleus and more NPY-ir cells in the cortex. AVT- and NPY-ir cells did not differ between unmated and mated females. Collectively, my results suggest that AVT and NPY play a role in regulating seasonal transitions in male reproductive behavior, rather than regulating migration per se. Further, these data indicate that both AVT and NPY are regulating reproductive behavior differently in males versus females. These data provide the framework for future studies examining the mechanisms regulating transitions between reproductive, migratory and foraging behaviors.

The study shows that multi-sided markets pose difficulties when the relevant product market is to be defined. These difficulties pertain to two questions. The first question is whether one or several markets should be defined. In this regard, it is not easy to extract a coherent method from the cases examined. Instead, the methods applied give the impression of ad hoc-solutions, where similar circumstances result in dissimilar outcomes. Indeed, it is hard to reconcile the different market definitions in Visa International MIF and MasterCard MIF. The uncertainties are not limited to these two cases, as the methods applied in Google Shopping too give rise to ambiguities. Why was the market for general search engine platforms separated into two distinct product markets, but the market for comparison shopping services encompassed both sides? Unfortunately, this discussion was not present in the decision. This only serves to reinforce the impression that these questions are solved on an ad hoc-basis. A clear method of approaching multi-sided markets is desirable, not least because the enforcement of competition rules must be characterized by consistency and foreseeability. Hopefully, the judgement in Google Shopping will bring further clarity to this. Nonetheless, the conclusion is that one market should be defined when differences between competitive constraints on the two sides are absent. E contrario, this means that two markets should be defined when such differences are present. This is true regardless of the market in question being a transaction or a non-transaction market. This method seems preferable to strictly adhering to the division of multi-sided markets into transaction or non-transaction markets. If the Commission’s analysis is correct in that there are no differences in competitive constraints on the two sides of comparison shopping services, in combination with crossing network effects, the platform’s multi-sidedness is a necessary trait for both sides. This means that a substitute has to be multi-sided in order for it to be included on the relevant product market, which minimizes the risk for false negatives. Vice versa, the definition of two markets allows for one-sided products to be included on the relevant product market, which minimizes the risk for false positives. This is important not only for the binary finding of dominance or non-dominance, but also the degree of dominance. As concluded above, incorrectly defining one market may artificially inflate the degree of dominance into false super-dominance, and incorrectly defining several markets may artificially dilute the degree of dominance. The second question is how substitutability should be measured. It is obvious from the cases examined that qualitative measures are used and not quantitative measures. The products’ characteristics, intended use, purpose, functionalities, users’ perceptions of the product, etc. were given much attention. The SSNIP test was not applied in any of the cases. The first conclusion to be drawn from the examination above is therefore that the difficulties regarding measuring substitutability on multi-sided markets mainly concern quantitative measures. The arguments against applying a SSNIP test related to the cellophane fallacy (in two different forms, one of which was deceivingly similar to the reverse cellophane fallacy) and differences in price sensitivities between the two sides. Network effects present an additional difficulty, which may lead to exaggerated results when measuring substitutability. The second conclusion to be drawn is that there exists a reluctance to apply a SSNIP test in a way that is tailored for multi-sided markets. One method that has been proposed is to apply the test on the total sum paid by both sides, while allowing the intermediary to adjust the increase in price in accordance with its price structure. The categorical dismissal of applying the test in this way suggests that adapted versions have some time to wait before being introduced into case law and decisional practice. If they, as their proponents argue, are a robust way of broadening the evidence of possible substitutability, this is unfortunate. The risk of defining the market overly narrow or overly broad is of course present in this regard as well. A broader spectrum of evidence therefore minimizes the risk of incorrectly finding both dominance and non-dominance.

Graduation date: 2006 / Most vertebrates exhibit seasonality in many life history traits. Such seasonal rhythms are temporally organized via the transduction of environmental cues (e.g., photoperiod, temperature) into appropriate endocrine signals. However, among ectothermic vertebrates that undergo continuous winter dormancy, temperature is the only environmental cue available for synchronizing seasonal rhythms. Most intriguing is that in species where reproduction occurs immediately following spring emergence, the associated changes in neurophysiology and behavior that accompany reproduction likely occur during winter dormancy. The purpose of this dissertation research was to explore the mechanisms by which temperature cues affect the chronobiology and seasonal reproduction of red-sided garter snakes (Thamnophis sirtalis parietalis). Because of their roles in circadian organization and energy balance, melatonin and corticosterone are likely hormonal components of these time-keeping systems. I first characterized the interactions between melatonin and corticosterone to better understand the hormonal mechanisms facilitating temperature-induced reproduction. Melatonin and corticosterone additively inhibit reproductive behavior during the spring mating season. Experimental manipulations with a serotonin receptor antagonist suggest the mechanism underlying these effects involves a serotonin-regulated system. Although melatonin does not influence corticosterone responses to capture stress, capture stress significantly increases melatonin concentrations. To investigate the functional significance of these interactions in regulating temperature-induced reproduction, I measured body temperatures of snakes as well as circadian melatonin and corticosterone cycles during winter dormancy and spring emergence using a combination of field and laboratory experiments. Surprisingly, an increase in body temperature is not necessary for emergence from winter dormancy. Rather, critically low temperatures may serve as a zeitgeber entraining an endogenous circannual cycle that regulates emergence. Decreased environmental temperatures, in the absence of changing photoperiod cues, modulate circadian melatonin and corticosterone rhythms during hibernation. Such temperature-induced changes in hormone rhythms may facilitate seasonal reproductive behavior following spring emergence. Furthermore, a phase-shift in corticosterone rhythms during the mating season may regulate the seasonal transition between reproductive and non-reproductive states in red-sided garter snakes. Such studies investigating the environmental and hormonal mechanisms underlying time-keeping systems may provide valuable insight into the potential impact of environmental perturbations (e.g., climate change) on seasonal rhythms in physiology and behavior.

No description available.

Aim The aim of the study was to investigate how different types of small-sided games (SSG) for girls in the ages between 12–21 years and how it affects the number of technical actions. How does the number of the total technical actions affect based on different types of small-sided games among girls in floorball and wich technical action differ? Method The Swedish floorball federation recruited one association with three different types of teams,younger red-level, older red-level and black level were the number of participants amounted to 39 outfield players and seven goalies with varied experience of exercise within the game of floorball. Data collection happened under respective teams ordinary training times where four different game forms of SSG were filmed. Each team was recorded one time in each gameform and each player got six shifts in each SSG and the shift length was one minute. Then the collected data from the video analysis was determined into an excel document and from that we put in the data in jamovi to analyze it and to see if there were any significance between the groups. Result There was no significant difference between the groups in the total amount of technical actions. The study shows that younger red has the most technical actions in 5 vs 5. The study also shows that red older has the most technical actions in 4 vs 4. In black level arose thegreatest number of technical actions in 3 vs 3. Conclusion The study will not be generalizable because of a low number of participants and no significance was reached which also previous research indicates. The conclusion of the study was that two age groups generated the most total number of technical actions in SSG while one age group generated the most total number of technical actions in a full-sized rink. The authors see trends on SSG produce more technical actions compared to a full-sized rink. More research is needed around SSG in floorball to see if this is the case. / <p>Jacob Cedervall är student på tränarprogrammet.</p><p>Sebastian Celander är student på ämneslärarprogrammet, specialidrott.</p>