10 resultados para Attention Bias
em Doria (National Library of Finland DSpace Services) - National Library of Finland, Finland
Resumo:
The general goal of the present work was to study whether spatial perceptual asymmetry initially observed in linguistic dichotic listening studies is related to the linguistic nature of the stimuli and/or is modality-specific, as well as to investigate whether the spatial perceptual/attentional asymmetry changes as a function of age and sensory deficit via praxis. Several dichotic listening studies with linguistic stimuli have shown that the inherent perceptual right ear advantage (REA), which presumably results from the left lateralized linguistic functions (bottom-up processes), can be modified with executive functions (top-down control). Executive functions mature slowly during childhood, are well developed in adulthood, and decline as a function of ageing. In Study I, the purpose was to investigate with a cross-sectional experiment from a lifespan perspective the age-related changes in top-down control of REA for linguistic stimuli in dichotic listening with a forced-attention paradigm (DL). In Study II, the aim was to determine whether the REA is linguistic-stimulus-specific or not, and whether the lifespan changes in perceptual asymmetry observed in dichotic listening would exist also in auditory spatial attention tasks that put load on attentional control. In Study III, using visual spatial attention tasks, mimicking the auditory tasks applied in Study II, it was investigated whether or not the stimulus-non-specific rightward spatial bias found in auditory modality is a multimodal phenomenon. Finally, as it has been suggested that the absence of visual input in blind participants leads to improved auditory spatial perceptual and cognitive skills, the aim in Study IV was to determine, whether blindness modifies the ear advantage in DL. Altogether 180-190 right-handed participants between 5 and 79 years of age were studied in Studies I to III, and in Study IV the performance of 14 blind individuals was compared with that of 129 normally sighted individuals. The results showed that only rightward spatial bias was observed in tasks with intensive attentional load, independent of the type of stimuli (linguistic vs. non-linguistic) or the modality (auditory vs. visual). This multimodal rightward spatial bias probably results from a complex interaction of asymmetrical perceptual, attentional, and/or motor mechanisms. Most importantly, the strength of the rightward spatial bias changed as a function of age and augmented praxis due to sensory deficit. The efficiency of the performance in spatial attention tasks and the ability to overcome the rightward spatial bias increased during childhood, was at its best in young adulthood, and decreased as a function of ageing. Between the ages of 5 and 11 years probably at first develops movement and impulse control, followed by the gradual development of abilities to inhibit distractions and disengage attention. The errors especially in bilateral stimulus conditions suggest that a mild phenomenon resembling extinction can be observed throughout the lifespan, but especially the ability to distribute attention to multiple targets simultaneously decreases in the course of ageing. Blindness enhances the processing of auditory bilateral linguistic stimuli, the ability to overcome a stimulus-driven laterality effect related to speech sound perception, and the ability to direct attention to an appropriate spatial location. It was concluded that the ability to voluntarily suppress and inhibit the multimodal rightward spatial bias changes as a function of age and praxis due to sensory deficit and probably reflects the developmental level of executive functions.
Resumo:
Selostus: Eläinmalliin perustuvien hiehojen odotusarvojen luotettavuus jalostusarvon ennusteena
Resumo:
Työn tarkoituksena oli kehittää mittauselektroniikka puutislepinnoitusprosessin ohjaukseen. Mittauselektroniikalla on tarkoitus mitata pikoampeeriluokan virtoja mittaanturilta, jossa virtaa kuuma, noin 250 ºC asteinen kaasu. Mitta-anturin toiminta perustuu ioniliikkuvuusspektrometriaan. Työssä tutkitaan pikoampeeriluokan virtojen mittaamista sekä mittauskytkennöissä käytetyn virta-jännitemuuntimen ominaisuuksia ja mitoittamista. Työ tarkastelee myös T-kytkennän käyttöä vahvistimen takaisinkytkennässä. Jännitekertojakytkentöjä käsitellään teoreettisesti mitta-anturin biasjännitteiden luomiseksi vähäisellä piirilevypinta-alalla. Työssä suunniteltiin mittauselektroniikan esivahvistinprototyypit sekä mitta-anturin biasjännitekytkentä. Mitta-anturin kuumien olosuhteiden vuoksi on mittauselektroniikka siirrettävä etäämmäksi mitta-anturista. Prototyyppikytkennöillä sekä laboratoriomittauksilla selvitettiin mittauselektroniikan esivahvistimien siirtämiseen liittyviä ongelmia. Biasjännitekytkennän suunnittelussa pyrittiin kytkentä toteuttamaan mahdollisimman vähällä piirilevypinta-alalla. Mittauselektroniikka todettiin laboratoriomittausten perusteella toimivaksi puutislepinnoitusprosessissa suoritettavia koemittauksia varten.
Resumo:
Tutkielmassa analysoidaan kolmen internetsivuston uutisartikkeleita kielitieteen näkökulmasta. Tavoitteena on selvittää esiintyykö internetsivustojen BBC, CNN ja Fox News uutisoinnissa politiikkaan liittyviä ennakkoasenteita tai puolueellisuuksia ja miten ne käytännössä näkyvät uutisartikkeleiden kielessä. Kriittiseen diskurssianalyysiin pohjautuen tutkielma esittelee jokaisen uutissivuston taustaan (esimerkiksi rakenteeseen ja rahoitukseen) liittyviä seikkoja sekä mediadiskurssiin ja politiikkaan liittyvät taustatiedot, jolla taataan Norman Fairclough'n kolmivaiheisen menetelmän mahdollisimman perusteellinen toteuttaminen. Uutissivustoja analysoidaan kriittiselle diskurssianalyysille sopivan funktionaalisen kieliopin ja muiden lingvististen välineiden avulla. Koko aineiston (404 artikkelia) otsikot analysoidaan ensin, minkä jälkeen analysoidaan yhdeksän kokonaista artikkelia kolmeen eri aihealueeseen liittyen niin, että jokaiselta internetsivustolta analysoidaan yksi artikkeli jokaista aihetta kohden. Analyysikeinoina käytetään ensisijaisesti systeemis-funktionaalisen kieliopin tekstuaalisen metafunktion välineitä (thematic structure). Myös ideationaalisen metafunktion välineitä (transitivity), referenssiketjuja (referential identity chains) ja leksikaalista analyysia käytetään hyväksi. Lähtökohtaisesti tavoitteena on analysoida uutissivustoja vertailevasti, jolloin analyysin tulokset ovat paremmin havainnoitavissa ja perusteltavissa. Hypoteesi aikaisempien tutkimusten ja yleisen mielikuvan perusteella on, että CNN uutisoi demokraattipuolueelle ja Fox News taas republikaanipuolueelle edulliseen sävyyn. Tutkimustulokset vaihtelivat hypoteesia tukevista ja sen vastaisista tuloksista niihin, jotka eivät olleet tarpeeksi tuettuja kumpaankaan suuntaan. Vahvimmat tulokset ovat kuitenkin hypoteesia tukevia, joten tässä tutkielmassa todetaan, ettei uutisointi ole puolueetonta ainakaan näiden kolmen internetsivuston kohdalla. Lisäksi muutaman aihealueen kohdalla uutisointi on niin toistuvaa tietystä näkökulmasta, että luonnollistumisteorian mukaista aatteiden luonnollistumista saattaa tapahtua. Tutkielmassa käytettyjen menetelmien menestyksen perusteella suositellaan, että tekstuaalisen metafunktion analyysivälineitä käytetään enemmän. Lisäksi suositellaan meta-analyysin harkitsemista, jotta voitaisiin selvittää, mitkä analyysimetodit parhaiten sopivat minkäkinlaisen aineiston analysointiin.
Resumo:
The behavioural finance literature expects systematic and significant deviations from efficiency to persist in securities markets due to behavioural and cognitive biases of investors. These behavioural models attempt to explain the coexistence of intermediate-term momentum and long-term reversals in stock returns based on the systematic violations of rational behaviour of investors. The study investigates the anchoring bias of investors and the profitability of the 52-week momentum strategy (GH henceforward). The relatively highly volatile OMX Helsinki stock exchange is a suitable market for examining the momentum effect, since international investors tend to realise their positions first from the furthest security markets by the time of market turbulence. Empirical data is collected from Thomson Reuters Datastream and the OMX Nordic website. The objective of the study is to provide a throughout research by formulating a self-financing GH momentum portfolio. First, the seasonality of the strategy is examined by taking the January effect into account and researching abnormal returns in long-term. The results indicate that the GH strategy is subject to significantly negative revenues in January, but the strategy is not prone to reversals in long-term. Then the predictive proxies of momentum returns are investigated in terms of acquisition prices and 52-week high statistics as anchors. The results show that the acquisition prices do not have explanatory power over the GH strategy’s abnormal returns. Finally, the efficacy of the GH strategy is examined after taking transaction costs into account, finding that the robust abnormal returns remain statistically significant despite the transaction costs. As a conclusion, the relative distance between a stock’s current price and its 52-week high statistic explains the profits of momentum investing to a high degree. The results indicate that intermediateterm momentum and long-term reversals are separate phenomena. This presents a challenge to current behavioural theories, which model these aspects of stock returns as subsequent components of how securities markets respond to relevant information.
Resumo:
Celebrity endorsement has increased in popularity over the past decades and companies are willing to spend increasingly excessive amounts of money into it. Even though multiple studies support celebrity endorsement, further research on its impact on advertising effectiveness is called for. Fur-ther, the role of consumers’ product class involvement in advertising needs to be further studied. The purpose of this study is to explore if consumers’ product class involvement and exposure to celebrity endorsers affect consumers brand recall. Supported by earlier studies, brand recall was used as a measure for advertising effectiveness in this study. In general, a psychological approach was chosen for building the theoretical framework. Concept of classical conditioning was presented in order to understand why people act how they do. Balanced theory and meaning transfer model were presented in order to study how celebrities can be used effectively in advertising context. Further, the importance of product class involvement in advertising effectiveness was evaluated. Hypotheses were formulated based on a literature review of the existing research. Because of the versatility of the research design, a mixed methods approach for this study was adopted. Empirical part of the study was conducted in three stages. First, a pre-test was conducted in order to choose suitable product endorsers for the advertisement stimuli used in the experiment. Second, an eye-tracking experiment with 30 test subjects was conducted in order to study how people view advertisements and whether the familiarity of the product endorser and consumers’ product class involvement affects brand recall. For the experiment, a fictional brand was created in order to avoid bias on brand recall. Third, qualitative interviews for 15 test subjects were conducted in the post-experiment stage in order to gain deeper understating of the phenomenon and to make sense of the findings from the experiment. Findings from this study support celebrity endorsement by suggesting that a famous spokesperson does not steal attention from brand information more than a non-celebrity product endorser. As a result, the use of a celebrity endorser did not decrease brand recall. Results support earlier research as consumer’ higher product class involvement resulted in a better brand recall. Findings from the interviews suggest that consumers have positive perceptions of celebrity endorsement in general. However, the celebrity–brand congruence is a crucial factor when creating attitudes towards the advertisement. Future research ideas were presented based on the limitations and results of this study