This dissertation analyzes trading behavior in financial markets from multiple perspectives. In chapter 1, "Exploratory Trading," I investigate the mechanisms underlying high-frequency traders' capacity to profitably anticipate price movements. I develop a model of how a trader could gather valuable private information by using her own orders in an exploratory manner to learn about market conditions. The model's predictions are borne out empirically, and I find that this "exploratory trading" model helps to resolve several central open questions about high-frequency trading. Chapters 2 and 3 focus on the trading behavior of individuals. Chapter 2, "Foundations of the Disposition Effect: Experimental Evidence," (co-authored with Johanna Mollerstrom), presents and analyzes results from a laboratory experiment intended to examine if and how "regret aversion"--aversion to admitting mistakes--affects people's trading decisions. Although the experimental results resolve little about regret aversion specifically, they reveal some novel and unexpected effects, most importantly that subjects radically changed their trading decisions when they were compelled to devote a minimal amount of extra attention. In chapter 3, "Price Targets," I analyze how rational investors who privately observe information of indeterminate quality use prices to learn about whether or not their private information is valuable. I derive implications about trading behavior that not only help to explain a variety of empirical puzzles, but also generate several new testable predictions. Although these three essays differ considerably in methodology and focus, they all address the same basic issue of understanding the foundations of trading behavior. / Economics

The purpose of this qualitive content analysis is to examine and analyse how children are visualized in toy catalogs, depending on their gender, 2014 - 2015.   It is important to observe how advertisement maintains the gender stereotypes norms of our society, since it has a major impact on our self-image and identity. Especially when it comes to children, who absorb everything and also because it is during the childhood the socialization process begins.   It is common that toy stores and toy catalogs distinguish boy toys from girl toys, based on the toy’s colour, form and function. This phenomena has become a topic of public discussion in recent years. Therefore, the two large toy companies, BR-leksaker and Toys “R” Us, claim to have published gender neutral toy catalogs by changing the gender roles and letting boys and girls play together with the same toys.   In order to gain more knowledge of toys impact on gender roles, we studied previous research by scientist in the field of gender, e.g. Almqvist, Butler and Connell. By using a qualitative method with a semiotic perspective, we found recurrent underlying aspects in the advertisements, by the selection of twelve pictures. The studies result implies that the studied toy catalogs are not yet equal, although a certain level of progress can be ascertained. Not even the three most equal advertisements visualized girls and boys equally, because of details such as stereotypical hairstyles, accessories and clothing. Furthermore, the study shows that girls are portrayed with boy toys than vice versa, which implies that boys are to a greater extent regarded as abnormal.

Coverage in a Wireless Sensor Network reflects how well a sensor network monitors an area. Many times it is impossible to provide full coverage. The key challenges are to prolong the lifetime and ensure connectivity to provide a stable network. In this thesis we first define p-percent coverage problem in which we require only p% of the whole area to be monitored. We propose two algorithms, Connected P-Percent Coverage Depth First Search (CpPCA-DFS) and Connected P-Percent Connected Dominating Set (CpPCA-CDS). Through simulations we then compare and analyze them for their efficiency and lifetime. Finally in conclusion we prove that CpPCA-CDS provides 5 to 20 percent better active node ratio at low density. At high node density it achieves better distribution of covered area however the lifetime is only 5 to10 percent shorter then CpPCA-DFS. Overall CpPCA-CDS provides up to 30 percent better distribution of covered area.

A multiwavelength investigation is conducted for nineteen blazar-type active galactic nuclei. Studies of variability timescales and flux duty cycles are performed at x- and gamma-rays for each source, with the relationship between flux and spectral index also being probed at gamma wavelengths. The correlation between these two energy ranges is also investigated, by utilising the Discrete Correlation Function with both one and ten day binning. The sources were chosen for their availability over a range of different x- and gamma-ray data sources: observations utilised include 0.2 - 150 keV x-ray data from the Swift mission and 200 MeV- 300 GeV gamma-ray data from the Fermi mission. Daily-binned Fermi data is used to calculate the smallest rise and decay e-folding times in gamma for each source. The results range from 0.4 to 21 days, corresponding to limits on the size of the gamma emission region ranging from Rd^-1 = 4.39 x 10^12 to Rd^-1 = 5.14 x 10^14 m. Flux duty cycles for fourteen sources are created from Fermi data, with six displaying structure at high fluxes that indicate flaring states have occured. Five of these six sources also display clear flares in their light curves, confirming these results. The relationship between the flux and the spectral index shows eight of nineteen sources exhibit harder-when-brighter behaviour. Four of these eight have been previously confirmed to display such behaviour. Results from the Discrete Correlation Function show a correlation at a time lag of ~ 600 days for H 1426+428, of uncertain origin. Gaussian functions are fitted to possible near-zero peaks in 3C 66A, 3C 454.3 and Mrk 421, which could be indicative of a synchrotron self-Compton component to the emission of these objects.

Walking for active transportation (AT) has been associated with individuals meeting the recommended physical activity levels. Global and local (i.e., Saskatoon) reported walking rates are low. Barriers perceived as a challenge (i.e., frequent and limiting) may influence walking. Individual differences, such as self-regulatory efficacy (SRE), may help people persist in overcoming challenging barriers, with those being more efficacious having greater persistence than their lower efficacy counterparts. The overall purpose of the present self-efficacy theory-based study was to examine whether individuals with higher and lower SRE differed in their persistence to overcome barriers to walking to/from a university campus under two experimental conditions (i.e., higher versus lower challenge). The experimental study design was a two (between: higher versus lower SRE to overcome barriers) by two (within: higher versus lower challenge vignette) mixed factorial, with three measures of persistence as the dependent variables (i.e., number of written solutions to overcoming barriers, time taken to record the solutions, and anticipatory perseverance to overcome barriers to walking in the near future). Based on self-efficacy theory and past research, individuals who had higher SRE were expected to have significantly higher persistence than their lower SRE counterparts after reading the higher challenge vignette. Participants were young adults who walked to/from a university campus. Higher and lower SRE groups were identified via a median split (nhigher = 22; nlower = 23). Each participant read a higher and lower challenge vignette (i.e., order counterbalanced across participants) in a lab-based setting, followed by completion of persistence measures after each vignette reading. Findings from a series of two by two ANOVAS provided partial support of the study hypothesis. A significant interaction between SRE groups and challenge vignettes was found with the persistence measure of time spent reporting coping solutions, F(1,43) = 4.64, p = .037. As expected, results from simple main effects showed the higher SRE group significantly differed from the lower SRE group under the higher challenge vignette condition, F (1,43) = 5.27, p = .027, by spending significantly more time reporting solutions. No other significant interactions were found between SRE groups x vignettes with the remaining measures of persistence: (1) number of reported solutions F (1,43) = 3.15, p = .083, and (2) anticipatory perseverance F (1,43) = 0.05, p = .82. The present study contributed new information on challenging barriers to walking for AT. Findings from the experiment partially supported contentions from self-efficacy theory about the importance of SRE beliefs to persistence when individuals are challenged. Future research should continue to examine the potential role that SRE beliefs play in whether individuals walk for AT.

Coated nanoparticles (CNP) are core-shell particles consisting of differing layers of epsilon positive (EP) and epsilon negative (ENG) materials. The juxtaposition of these EP and ENG materials can lead to the possibility of coupling incident plane waves to surface plasmon resonances (SPR) for particles even highly subwavelength in size. We introduce standard models of the permittivities of the noble metals used in these CNPs, and propose corrections to them based on experimental data when their sizes are extremely small. Mie theory is the solution to plane wave scattering by spheres and we extend the solution here to spheres consisting of an arbitrary number of layers. We discuss the resonance behaviors of passive CNPs with an emphasis on how the Coated nanoparticles (CNP) are core-shell particles consisting of differing layers of epsilon positive (EP) and epsilon negative (ENG) materials. The juxtaposition of these EP and ENG materials can lead to the possibility of coupling incident plane waves to surface plasmon resonances (SPR) for particles even highly subwavelength in size. We introduce standard models of the permittivities of the noble metals used in these CNPs, and propose corrections to them based on experimental data when their sizes are extremely small. Mie theory is the solution to plane wave scattering by spheres and we extend the solution here to spheres consisting of an arbitrary number of layers. We discuss the resonance behaviors of passive CNPs with an emphasis on how the resonance wavelength can be tuned by controlling the material properties and radii of the various layers in the configuration. It is demonstrated that these passive CNPs have scattering cross sections much larger than their geometrical size, but their resonance strengths are attenuated because of the inherent losses in the metals. To overcome this limitation, we show how the introduction of active material into the CNPs can not only overcome these losses, but can actually lead to an amplification of the scattering of the incident field. We report several optimized active CNP designs, including ones based on quantum dot gain media and study their performance characteristics with particular attention to the effect of the location of the gain material on the performance of these designs. We investigate the ability to control the scattered field directivity of the CNPs in both their far- and near-field regions and propose designs with minimal backscattering and those emulating macroscopic nanojets. We compare data generated by initial efforts to experimentally prepare CNPs and compare against analytical and numerical simulation results. Finally, we suggest a variety of interesting future research directions. resonance wavelength can be tuned by controlling the material properties and radii of the various layers in the configuration. It is demonstrated that these passive CNPs have scattering cross sections much larger than their geometrical size, but their resonance strengths are attenuated because of the inherent losses in the metals. To overcome this limitation, we show how the introduction of active material into the CNPs can not only overcome these losses, but can actually lead to an amplification of the scattering of the incident field. We report several optimized active CNP designs, including ones based on quantum dot gain media and study their performance characteristics with particular attention to the effect of the location of the gain material on the performance of these designs. We investigate the ability to control the scattered field directivity of the CNPs in both their far- and near-field regions and propose designs with minimal backscattering and those emulating macroscopic nanojets. We compare data generated by initial efforts to experimentally prepare CNPs and compare against analytical and numerical simulation results. Finally, we suggest a variety of interesting future research directions

Thermal mass can be used in buildings to reduce the need for and dependence on mechanical heating and cooling systems whilst maintaining environmental comfort. Active thermal mass strategies further enhance the performance of thermal mass through integration with the Heating, Ventilation and Air Conditioning (HVAC) systems. For the design of new buildings to include active thermal mass strategies, experience from operational projects and design guidelines are normally used by engineers. However, dynamic thermal modelling is required in most cases to accurately determine the performance of its integration with the environmental systems of the building. Design decisions made in the preliminary stages of the design of a building often determine its final thermal characteristics. At this stage, reasons for not integrating active thermal mass strategies include the lack of knowledge about the performance of previous buildings and the time and resources required to carry out detailed modelling. In this research project a commercially available dynamic building thermal program has been used to construct models for active thermal mass strategies and compare the results with monitored temperatures in buildings incorporating the strategies in the UK. Four active thermal mass strategies are considered (a) hollow core slabs (HCS), (b) floor void with mass, (FVWM) (c) earth-to-air heat exchanger (ETAHE) and (d) thermal labyrinth (TL). The operational strategies and monitoring are presented and their modelling is described in terms of geometrical configuration and input parameters. The modelling results are compared with the measured parameters successfully. Using the calibrated model, an excel based tool (TMAir) was then developed that can be used at the concept design stages of a typical office building to determine the benefits of integrating an active thermal mass strategy. Key design parameters were identified for each system. These parameters can be split into two categories; fixed parameters and user selected parameters. The fixed parameters are pre-selected for the design tool and have to be a fair representation of the projects that the tool will be used for. The user selected parameters are chosen by the user to represent the way the building will be used, and to look at the effect of key design decisions on the performance of the building. The tool has an easy-to-use interface which allows direct comparison of the different active thermal mass strategies together with the effects of changing key design parameters. Results are presented in terms of thermal comfort and energy consumption. TMAir has then been used to carry out a series of parametric analyses. These have concluded the following:  There is only a benefit in integrating a HCS strategy when night cooling is introduced  There is no benefit in integrating a FVWM strategy when only one parameter is improved  An ETAHE and TL strategy will always provide a benefit, although the benefits are greater when night cooling is introduced, solar and internal gains are reduced and when the air change rate is increased. When all of the parametric improvements are applied to the test room the results show that all of the active thermal mass strategies can provide a reduction in annual overheating hours when compared to the Standard Strategy. Only a small benefit is found for the FVWM Strategy, however around a 25% reduction is found for the HCS Strategy, over a 50% reduction for the TL Strategy and nearly a 75% reduction for the ETAHE Strategy. This demonstrates the importance of applying a low energy, passive approach when considering the application of active thermal mass strategies. The key results have shown that when comfort cooling is provided, adding a HCS or FVWM strategy always results in an increase in the annual cooling load. This is as a result of the temperature of the air being supplied into the cores or floor void being higher than that of the internal surface temperatures of the cores or void. This results in the supply air being heated, and less cooling provided to the test room per cooling energy delivered. Due to the pre cooling effect of the ETAHE and TL strategies, these strategies always result in a reduction in the annual cooling load. The key results have shown that the annual heating load is reduced by a small amount for the HCS and FVWM strategies unless the solar gains or internal gains are reduced, whereas the ETAHE and TL strategies always result in a around a 10% reduction in annual heating load as a result of the preheating effect these strategies have on the supply air.

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Ενεργά λέμε τα δίκτυα τα οποία επεξεργάζονται και τα περιεχόμενα (και όχι μόνο την επικεφαλίδα) των πακέτων που μετάγουν. Επικεντρωνόμαστε στα ενεργά δίκτυα ενθυλάκωσης, όπου ο προς εκτέλεση κώδικας συμπεριλαμβάνεται στα μεταγώμενα πακέτα, σε αντιδιαστολή με τους προγραμματιζόμενους μεταγωγείς. Παρουσιάζεται αναλυτικά το Active Networks Encapsulation Protocol (ANEP). Παρουσιάζονται δικτυακές εφαρμογές στις οποίες τα ενεργά δίκτυα βελτιώνουν την απόδοση της εφαρμογής και ταυτόχρονα μειώνουν τις απαιτήσεις σε δικτυακούς πόρους. Ακολούθως εστιάζουμε στην \"Ενεργή Αξιόπιστη Πολλαπλή Μετάδοση\", ένα πρωτόκολλο αξιόπιστης πολλαπλής μετάδοσης το οποίο χρησιμοποιεί την ενεργή μεταγωγή για να διαχειριστεί την ανάκτηση απωλειών πακέτων εντός του δικτύου (καταστολή NACK, λανθάνουσα μνήμη για πακέτα διόρθωσης, πολλαπλή μετάδοση περιορισμένης εμβάλειας). Παρέχονται αποτελέσματα προσομοιώσεων που υποστηρίζουν την θέση ότι ακόμα και με μικρό ποσοστό ενεργών κόμβων, ένα ενεργό δίκτυο μπορεί να βελτιώσει ουσιαστικά τις επιδόσεις της εφαρμογής και να μειώσει ταυτόχρονα την χρήση εύρους ζώνης. Κλείνοντας, κάνουμε κάποια τελικά σχόλια και εξάγουμε συμπεράσματα σχετικά με το υψηλό κόστος εγκατάστασης και συντήρησης των ενεργών δίκτυων, και πως αυτό αντιδιαστέλλεται με τα πλεονεκτήματα των τελευταίων σε σχέση με τις επιδόσεις των εφαρμογών και την χρήση των δικτυακών πόρων. / Active Networks are networks consisting (at least partially) of active nodes. A node is active if it doesn’t only processes a packet’s header in order to route it, but is also able to evaluate and process the packet’s payload. There are two kinds of active networks, depending on whether they are based on programmable switches or on capsules which bundle code together with the data. This dissertation focuses on the latter. The operational model of an active network of this kind comprises code execution models, network node management models and resource allocation policies. The Active Networks Encapsulation Protocol (ANEP) sets the mechanism for defining the platform required to evaluate the code that is encapsulated in the packet, as well the nodes’ behaviour when they do not support the required platform (drop the packet or simply forward it). This mechanism provides active networks with the flexibility to operate even when a very small percentage of the network’s node is actually active. There are various situations and where active networks can make better use of network resources. There are, for example, applications where different users might make similar, but different, requests resulting in unnecessary bandwith consumption when supported by conventional caching mechanisms. Active networks can provide smart caches that will dynamically synthesize pages from data cached by previous requests. Another situation where active networks can improve network performance is network applications like tele-conference, that depend heavily on new network services. Active networks allow for the faster deployment of new network services that enhance network speed and security and rationalise bandwidth usage through, for example multicast. Furthermore, active networks can support specialised applications, like for example on-line auctions, with custom-made network services. It is important to note that when measuring network performance, one should focus onto the network application’s performance, rather than network per-packet metrics like throughput and latency. In other words, intranetwork processing might increase both packet size and latency, but will improve the application’s end-to-end performance and reduce total network load. The protocols for three innovative network applications are presented: active reliable multicast, auctions over the network and remote sensor merging. For each of these we present network services that can be easily implemented and deployed in active networks to improve application performance. Finally, a more detailed analysis (by means of simulation) of an active reliable multicast protocol is presented. Active networks achieve two ends: on the one hand they push the idea of a network proxy to its logical end by effectively turning all network elements into smart proxies that provide caching, filtering, NACK suppression and other services. On the other hand they carry out part of the computation inside the network, bringing it closer to the data sources. When the computation is, for example, data merging this is beneficial to both the application and the network resources. This, however, can only be achieved at a cost. First of all in hardware, since network elements have to be upgraded from simple routers to full-blown computers capable of supporting Java and scripting languages. But also in latency, since packets have to undergo much more complex processing along the way that simple routing. In the applications presented here the costs associated with active transport are counter-balanced by the advantages the latter has to offer to the application as well as to the network. The bet that active networks have to win in order to get widely accepted, is to have enough active application protocols developed that their installation and maintenance cost can be justified.