In the first chapter of this dissertation, I examine the relationship between hedging and diversification effects on CEO compensation in the Real Estate Investment Trust (REIT) industry. The REIT industry is suitable for this investigation for various reasons; primarily being that the REIT sample represents a relatively clean sample to study the effects of diversification and hedging on compensations. I find a positive and significant relationship between the interaction variable which reflects the effects of both hedging and diversification and CEO pay-for-performance sensitivity. This is consistent with the notion that managers are in a better position to manage firm risk if they use all the available tools and instruments, including hedging and diversification. I also find a positive and significant relationship between hedging and CEO pay-for-performance sensitivity, indicating that CEO compensation is more short term oriented because hedging is a relatively short term risk reduction strategy. The second chapter of this dissertation examines the relative contribution of regular and e-mini futures market to price discovery of EUR/USD futures contracts on the CME, using intraday data in 2010. The relative contribution to price discovery is estimated using the information share approach proposed by Hasbrouck (1995) and Gonzalo and Granger (1995). Empirical findings indicate that regular futures market accounts for approximately 66.5% of price discovery in the EURO/USD market. This study also examines if the regular future’s information share (IS) can be explained by the positioning of commercial and non-commercial traders. The results support the conclusion that the IS of regular futures can be better explained by non-commercial traders (speculators) than commercial traders (hedgers).

Essa pesquisa faz um recorte da música eletrônica através de suas linguagens, práticas documentárias e processos informativos, estudados a partir de contextos socioculturais, para observar sua constituição como um gênero musical popular. A informatividade da música eletrônica foi compreendida em seus complexos de relações terminológicas e conjecturas diversas, ilustrando e identificando interrelações, propriedades estéticoformais, categorizações e características discursivas e linguísticas. Conceitos da Ciência da Informação e das humanidades foram utilizados para analisar como esse gênero irresoluto e fragmentado por muitas definições, processos anticategóricos e conflitos de distinção cultural, acaba por definir-se como um campo de intensa materialidade informativa e histórica, que segue tendo na ideia de \"música eletrônica\" seu universo simultaneamente amplo e circunscrito. Objetos, fenômenos, o devir musical, categorias e as linguagens dessa música foram estudados sob os vértices da informatividade, como proposta por Bernd Frohmann, conceito processual que surge a partir da ideia dos documentos como definidores e reveladores de contextos, problemáticas e discursos. Essa pesquisa conclui como a informatividade da música eletrônica logra documentá-la como tal: um gênero musical histórico, institucionalizado e documentado, coeso e problematizado por preponderantes aspectos informativos, referenciais e de categorização - um fenômeno da Cultura e da Informação. / This research outlines electronic music through its languages, documentary practices, informative processes and their sociocultural contexts, to observe its constituion as a popular music genre. The informativenesse of electronic music is seen from its complexes of terminology relations and several conjectures, that illustrate and identify interrelations, aesthetic and formal properties, categorizations, discursive and linguistic characteristics. Concepts from Information Science and other humanities have been used to analyze how this irresolute musical genre, fragmented by anti-categorical and cultural distinction conflits, ends up being defined as a field of intense informative and historical materiality. This music still relies this wide and also circumscribed universe on the idea of \"electronic music\". Objectos, phenomena, the music becoming, categories and languages of this music have been studied under the informativeness theorical vertices, as proposed by Bernd Frohmann, a procedural concept that arises from the ideia of documents as defining elements of contexts, discourses and problems. This research concludes how informativeness manages to document electronic music as such: a historical, institutionalized and documented musical genre, cohesive and also very problematized by its preponderant informative, referential and categorical aspects - a Cultural and Informative phenomenon.

O aumento da comparabilidade entre os países é uma das principais motivações para o apoio permanente à convergência aos padrões globais de contabilidade (SEC, 2010; Hail, Leuz & Wysocki, 2010). As informações contábeis são importantes na formação das expectativas do mercado, e, segundo Sarlo Neto, Lopes e Dalmácio (2009) tal importância influencia o valor das empresas e é conhecida como informatividade. A Comparabilidade afeta os usuários finais das demonstrações financeiras, porque as empresas pares servem como referência na análise das informações contábeis de uma empresa. Assim, o objetivo principal desta pesquisa foi investigar o impacto da comparabilidade dos demonstrativos financeiros sobre a acurácia na previsão de consenso dos analistas de investimento do mercado brasileiro e na informatividade das empresas listadas na BM&FBovespa no período de 2005 a 2015. Esta pesquisa é quantitativa, utiliza-se de dados secundários e é descritiva por investigar a influência da comparabilidade dos demonstrativos financeiros sobre a acurácia e previsão dos analistas de investimento do mercado brasileiro. Os dados foram coletados a partir do banco de dados dos sistemas Thomson ONE Analytics, Economática, e, Comdinheiro. Para tanto utilizou-se a técnica econométrica de regressão múltiplaA classificação por setor foi realizada utilizando-se o North American Classification System - NAICS nível 2; e para testar o comportamento das variáveis foi utilizada a abordagem estatística de dados em painel. Os principais resultados obtidos foram: a comparabilidade individual média entre empresas diferentes não apresentou variações significativas no período após adoção do IFRS, entretanto a comparabilidade da mesma empresa ao longo do período apresentou melhora. Em relação à acurácia não foram observadas alterações significativas nos períodos antes e após a transição regulatória. No entanto, observou-se que as variáveis COMPM e COMPT influenciam a acurácia de forma significativa e negativa. As variáveis COMPM e COMPT mostraram-se positivas e estatisticamente significativas, como principais variáveis que impactam no retorno das ações. / Increasing comparability across countries is one of the main motivations for continuing support for convergence to global accounting standards (SEC, 2010; Hail, Leuz & Wysocki, 2010). Accounting information is important in shaping market expectations, and according to Sarlo Neto, Lopes and Dalmácio (2009) such importance influences the value of companies and is known as information. Comparability affects the end users of financial statements because peer companies serve as a benchmark in analyzing a company\'s accounting information. The main objective of this research was to investigate the impact of the comparability of the financial statements on the accuracy in the consensus forecast of investment analysts in the Brazilian market and in the informativeness of the companies listed on BM & FBovespa between 2005 and 2015. This research is quantitative, we used secondary and descriptive data to investigate the influence of the comparability of financial statements on the accuracy and prediction of investment analysts in the Brazilian market. The data were collected from the Thomson ONE Analytics System Database, the Economics System Database, and Comdinheiro. For that, the econometric technique of multiple regression was used with the aid of Stata® and SPSS® Software. The classification by sector was made using the classification of the North American Classification System - NAICS level 2; and to test the behavior of the variables the statistical approach of panel data was used. As the main results: the average individual comparability between different companies did not show significant variations in the period after adoption of IFRS, however the comparability of the same company during the period showed an improvement in the period. Regarding the accuracy, no significant changes were observed in the periods before and after the regulatory transition. However, it was observed that the COMPM and COMPT variables influence the accuracy significantly and negatively. The variables COMPM and COMPT were positive and statistically significant, as the main variables that impact on stock returns.

This thesis presents three empirical chapters investigating the informativeness of aggregate insider trading activities in the UK’s stock and option markets. Chapter one examines the relationship between aggregate insider trading and stock market volatility. The results suggest a positive relationship between aggregate insider trading and stock market volatility, confirming the hypothesis that aggregate insider trading increases the rate of flow of information into the stock market which in turn increases stock market volatility. Given that insiders also trade for non-informational reasons, we distinguish between informative and noisy insider trades and examine whether they affect stock market volatility differently. We find that only aggregate insider buy trades and medium sized insider trades affect stock market volatility positively. Chapter two re-examines whether aggregate insider trading can help predict future UK stock market returns. The results suggest that there is information in aggregate insider trading that can help predict future stock market returns. This is due to aggregate insiders’ ability to time the market based on their possession of superior information about unexpected economy-wide changes. We also find that a positive shock in aggregate insider trading causes an increase in future stock market returns two months after the shock. We test whether there is information in medium insider trades that can help predict future stock market returns. The results suggest that medium insider trades, specifically medium insider buy trades can help predict future stock market returns. Lastly, chapter three explores the relationship between aggregate exercise of executive stock options (ESO) and stock market volatility. Insiders in possession of private information may use their informational advantage to trade in the option markets via their exercise of ESOs which may affect stock market volatility. We find that aggregate exercise of ESOs affect stock market volatility positively. This is due to an increase in the rate of flow of information released via private information motivated exercises which cause prices to move as they adjust to the new information thereby increasing volatility. When executives have private information about future stock performance, they are motivated to exercise and sell stocks post exercise to avoid losses. They are also motivated to exercise and sell only a proportion of their stocks, specifically more than 50% of the acquired stocks and they exercise near the money ESOs. We find that for all these private information motivated reasons to exercise ESOs, stock market volatility is positively affected.

O aumento da comparabilidade entre os países é uma das principais motivações para o apoio permanente à convergência aos padrões globais de contabilidade (SEC, 2010; Hail, Leuz & Wysocki, 2010). As informações contábeis são importantes na formação das expectativas do mercado, e, segundo Sarlo Neto, Lopes e Dalmácio (2009) tal importância influencia o valor das empresas e é conhecida como informatividade. A Comparabilidade afeta os usuários finais das demonstrações financeiras, porque as empresas pares servem como referência na análise das informações contábeis de uma empresa. Assim, o objetivo principal desta pesquisa foi investigar o impacto da comparabilidade dos demonstrativos financeiros sobre a acurácia na previsão de consenso dos analistas de investimento do mercado brasileiro e na informatividade das empresas listadas na BM&FBovespa no período de 2005 a 2015. Esta pesquisa é quantitativa, utiliza-se de dados secundários e é descritiva por investigar a influência da comparabilidade dos demonstrativos financeiros sobre a acurácia e previsão dos analistas de investimento do mercado brasileiro. Os dados foram coletados a partir do banco de dados dos sistemas Thomson ONE Analytics, Economática, e, Comdinheiro. Para tanto utilizou-se a técnica econométrica de regressão múltiplaA classificação por setor foi realizada utilizando-se o North American Classification System - NAICS nível 2; e para testar o comportamento das variáveis foi utilizada a abordagem estatística de dados em painel. Os principais resultados obtidos foram: a comparabilidade individual média entre empresas diferentes não apresentou variações significativas no período após adoção do IFRS, entretanto a comparabilidade da mesma empresa ao longo do período apresentou melhora. Em relação à acurácia não foram observadas alterações significativas nos períodos antes e após a transição regulatória. No entanto, observou-se que as variáveis COMPM e COMPT influenciam a acurácia de forma significativa e negativa. As variáveis COMPM e COMPT mostraram-se positivas e estatisticamente significativas, como principais variáveis que impactam no retorno das ações. / Increasing comparability across countries is one of the main motivations for continuing support for convergence to global accounting standards (SEC, 2010; Hail, Leuz & Wysocki, 2010). Accounting information is important in shaping market expectations, and according to Sarlo Neto, Lopes and Dalmácio (2009) such importance influences the value of companies and is known as information. Comparability affects the end users of financial statements because peer companies serve as a benchmark in analyzing a company\'s accounting information. The main objective of this research was to investigate the impact of the comparability of the financial statements on the accuracy in the consensus forecast of investment analysts in the Brazilian market and in the informativeness of the companies listed on BM & FBovespa between 2005 and 2015. This research is quantitative, we used secondary and descriptive data to investigate the influence of the comparability of financial statements on the accuracy and prediction of investment analysts in the Brazilian market. The data were collected from the Thomson ONE Analytics System Database, the Economics System Database, and Comdinheiro. For that, the econometric technique of multiple regression was used with the aid of Stata® and SPSS® Software. The classification by sector was made using the classification of the North American Classification System - NAICS level 2; and to test the behavior of the variables the statistical approach of panel data was used. As the main results: the average individual comparability between different companies did not show significant variations in the period after adoption of IFRS, however the comparability of the same company during the period showed an improvement in the period. Regarding the accuracy, no significant changes were observed in the periods before and after the regulatory transition. However, it was observed that the COMPM and COMPT variables influence the accuracy significantly and negatively. The variables COMPM and COMPT were positive and statistically significant, as the main variables that impact on stock returns.

In the first essay titled "Shareholder Coordination, Information Diffusion and Stock Returns", we show that the quality of information sharing networks linking firms' institutional investors has stock return predictability implications. First, we demonstrate that firms with high shareholder coordination experience less local comovement and less post earnings announcement drift, consistent with the notion that coordination improves firms' information environment. We then document that the stock return performance of firms with high shareholder coordination leads that of firms with low shareholder coordination, supporting the view that coordination acts as an information diffusion channel. Finally, we provide evidence consistent with the notion that the market does not readily recognize the superior quality of high shareholder coordination firms and prices it gradually through the trading of sophisticated institutional investors, thereby causing future returns to be positively associated with shareholder coordination. In the second essay titled "Shareholder Coordination and Stock Price Informativeness", we find that stock prices of firms with better information sharing networks linking institutional shareholders exhibit higher levels of idiosyncratic volatility. This positive relation between shareholder coordination and stock price informativeness is mainly driven by coordination among dedicated and independent institutions and exists even after accounting for endogeneity. We further show that institutional trading serves as an information diffusion channel that strengthens the relationship of shareholder coordination with price informativeness. Overall, our results indicate that a higher degree of shareholder coordination leads to more informative stock prices by encouraging the collection of and trading on private information.

Purpose: To explore what are the consumers’ attitudes towards mobile advertising in a social media context. Research questions: What are the consumers’ attitudes towards entertainment, credibility, irritation and informativeness in mobile advertising? What are the consumers’ attitudes towards permission-based advertising and incentivebased advertising in mobile advertising in social media context? Theoretical framework: This study was based on theories that helped to understand what are the consumers’ attitudes towards mobile advertising, what are the attitudes towards the dimensions of mobile advertising and the types of mobile advertising. A model was presented in order to have a clear picture of the existing theories in this field. Methodology: The authors used a qualitative research and the method chosen for data collection was semi-structured interviews and a case study, Snapchat (mobile application). Conclusions: After this process the authors could conclude that consumers’ attitudes towards mobile advertising in social media were negative. The strongest feeling among consumers that would influence their attitudes was irritation. The consumers’ negative attitudes can be related to control. When giving them control their attitudes can be positive. Rewards can positively influence consumers’ attitudes as well. According to the findings in this study high rewards should be given to consumers in high engagement situations.

This dissertation consists of three essays. The first essay examines a general theory of information based on informal contracting. The measurement problem—the disparity of true and measured performances—is at the core of many failures in incentive systems. Informal contracting can be a potential solution since, unlike in formal contracting, it can utilize a lot of qualitative and informative signals. However, informal contracting must be self-enforced. Given this trade-off between informativeness and self-enforcement, I show that a new source of statistical information is economically valuable in informal con- tracting if and only if it is sufficiently informative that it refines the existing pass/fail criterion. I also find that a new information is more likely valuable, as the stock of existing information is large. This information theory has implications on the measurement problem, a puzzle of relative performance evaluation and human resources management. I also provide a methodological contribution. For tractable analysis, the first-order approach (FOA) should be employed. Existing FOA-justifying conditions (e.g. the Mirrlees-Rogerson condition) are so strong that the information ranking condition can be applied only to a small set of information structures. Instead, I find a weak FOA- justifying condition, which holds in many prominent examples (with multi- variate normal or some of univariate exponential family distributions). The second essay analyzes the effectiveness of managerial punishments in mitigating moral hazard problem of government bailouts. Government bailouts of systemically important financial or industrial firms are necessary ex-post but cause moral hazard ex-ante. A seemingly perfect solution to this time-inconsistency problem is saving a firm while punishing its manager. I show that this idea does not necessarily work if ownership and management are separated. In this case, the shareholder(s) of the firm has to motivate the manager by using incentive contracts. Managerial punishments (such as Obama’s $500,000 bonus cap) could distort the incentive-contracting program. The shareholder’s ability to motivate the manager could then be reduced and thereby moral hazard could be exacerbated depending on corporate governance structures and punishment measures, which means the likelihood of future bailouts increases. As an alternative, I discuss the effectiveness of shareholder punishments. The third essay analyzes how education affect workers’ career-concerns. A person’s life consists of two important stages: the first stage as a student and the second stage as a worker. In order to address how a person chooses an education-career path, I examine an integrated model of education and career-concerns. In the first part, I analyze the welfare effect of education. In Spence’s job market signaling model, education as a sorting device improves efficiency by mitigating the lemon market problem. In my integrated model, by contrast, education as a sorting device can be detrimental to social welfare, as it eliminates the work incentive generated by career-concerns. In this regard, I suggest scholarship programs aimed at building human capital rather than sorting students. The second part provides a new perspective on education: education is job-risk hedging device (as well as human capital enhancing or sorting device). I show that highly risk-averse people take high education in order to hedge job-risk and pursue safe but medium-return work path. In contrast, lowly risk-averse people take low education, bear job-risk, and pursue high-risk high-return work path. This explains why some people finish college early and begin start-ups, whereas others take master’s or Ph.D. degrees and find safe but stable jobs. / text

Dytiscidae, contains numerous endemic and non-endemic species on Madagascar. Their evolutionary history is largely unknown on the island. Herein, I use analyses to infer phylogenetic relationship among groups of diving beetles, with a focus on the subfamily Dytiscinae and endemic species in two other groups of Dytiscidae. Paper I represents the first phylogenetic reconstruction focusing on the tribe Aciliini based on molecular data. Several commonly used molecular markers, as well as a new marker for Hydradephagan beetles, were evaluated in this study. Our analyses suggest that six genera within Aciliini are monophyletic. The most basal clades with Neotropical and Afrotropical taxa suggest a possible Gondwanan origin. Evaluation of gene fragments indicated CAD to be the most informative marker. Paper II focuses on colonization and radiation events of large bodied endemic diving beetles of the tribes Cybistrini and Hydaticini on Madagascar. Colonization events were inferred from dated phylogenetic trees and ancestral biogeographical reconstructions. Our results suggest both multiple colonizations, and out-of-Madagascar dispersal events, mostly during the Miocene and Oligocene. In paper III, we revised the Rhantus species of Madagascar. We used both molecular and morphological data to evaluate species hypothesis and emphasized the value of Manjakatompo – one of the last remaining fragments of central highland forests. In Paper IV we reconstruct the phylogeny and use Species Distribution Modelling for the endemic genus Pachynectes in Madagascar. Our sampling has discovered that the species diversity of Pachynectes is at least three times higher than previously believed. It seems that allopatric speciation was the main driver, which led to the diversity of Pachynectes. Our results suggest that climatic gradients and the five main biomes were a better predictor than watershed systems in explaining the distribution pattern and speciation between sister species. / Dykarskalbaggar i familjen Dytiscidae finns över hela världen och kan hittas i såväl temporära som permanenta vattensamlingar, i rinnande såväl som i stillastående akvatiska habitat. Bland dykarskalbaggarna finns ett hundratal både endemiska och icke-endemiska arter på Madagaskar. Deras evolutionära historia på denna mytomspunna ö är dock i stort sett okänd. I den här avhandlingen använder jag molekylära data och analyser för att härleda evolutionära släktskap, s.k. fylogenier eller släktträd, för olika grupper av dykarskalbaggar med fokus på underfamiljen Dytiscinae samt endemiska arter från två andra grupper på Madagaskar. Artikel 1 är den första molekylär-fylogenetiska studien som gjort på tribuset Aciliini. Flera molekylära markörer (delar av gener) användes samt utvärderades, inklusive den nya markören CAD för Hydradephaga skalbaggar. Analysen bekräftar att tribuset Aciliini är en monofyletisk grupp (naturlig grupp som härstammar från en gemensam förfader) samt att Eretini är närmaste släktingen. Alla sex släkten med flera arter i tribuset stöddes också som monofyletiska, det sjunde släktet har bara en art. De mest basala grupperna i trädet utgjordes av Neotropiska och Afrotropiska arter vilket antyder ett ursprung på Gondwana kontinenten. Denna slutsats var dock beroende av för vilken nod i trädet (av två möjliga) som ett fossil användes som kalibreringspunkt. Utvärderingen av de olika genfragmenten ledde till slutsatsen att CAD var den mest informativa genen tätt följd av en annan nukleär proteinkodande gen, WNT. Artikel 2 fokuserar på kolonisations- och artbildningshändelser för två grupper av relativt stora dykarskalbaggar. Denna studie bygger på två tidigare publicerade dataset där vi lade till Madagaskars arter. Kolonisationshändelser härleddes genom daterade molekylära släktträd samt rekonstruktion av förfäders biogeografiska utbredningsområden. Resultaten visade både på ett flertal separata koloniseringshändelser men också "ut-ur-Madagaskar" spridning, framförallt under tidsperioden Miocen-Oligocen. Studien visade också att inga koloniseringshändelser lett till några signifikanta artradiationer på Madagaskar i dessa två grupper. I Artikel 3 reviderar vi arterna av släktet Rhantus som finns på Madagaskar, vilka alla är begränsade i sin utbredning till den centrala högplatån på Madagaskar. Vi använder både morfologi och molekylära data för att testa arthypoteser samt bestyrker det bevarandebiologiska värdet av Manjakatompo-skogen, ett av de allra sista fragmenten av skog på den centrala högplatån. I Artikel 4 härleder vi släktskapet för det endemiska rinnande-vatten släktet Pachynectes samt analyserar de ingående arternas utbredning genom modellering. Våra insamlingar runt om Madagaskar har visat att artdiversiteten i släktet är minst tre gånger så hög som man tidigare trott. Genom att integrera släktskapsanalys med utbredningsmodellering söker vi få en inblick i vad som drivit artbildningen i en endemisk artradiation. Allopatrisk artbildning verkar varit den huvudsakliga typen av artbildning inom Pachynectes. Vi testade även två huvudhypoteser som söker förklara mikroendemisk artbildning generellt på Madagaskar. Våra resultat visar att klimatgradienter och de fem huvudsakliga biomen på Madagaskar verkar ha en långt bättre förklaringsgrad än stora floder och avrinningsområden för att förklara Pachynectes arternas utbredning och släktskap. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.</p>

Darbo tikslas - nustatyti ir įvertinti asmens svaikatos priežiūros įstaigų medicinos personalo (gydytojų radiologų ir radiologijos laborantų) informuotumą apie pacientų gaunamą apšvitą ir radiacinę saugą Vilniaus mieste. Tyrimo objektas – gydytojai radiologai ir radiologijos laborantai. Tyrimo metu buvo apklausti 140 respondentų iš 15 asmens sveikatos priežiūros įstaigų. Viso buvo apklausta 35 gydytojai radiologai (iš jų 15 vyrų ir 20 moterų) ir 105 radiologijos laborantai (iš jų 4 vyrai ir 101 moteris), o tai atitinkamai sudarė 25,0% ir 75,0%. Apklaustųjų amžius svyruoja nuo 23 iki 71 metų (vidurkis 47,43). Tyrimo tikslui ir uždaviniams pasiekti panaudotas aprašomasis tyrimo tipas bei anketinės apklausos metodas. Statistinė duomenų analizė atlikta naudojant SPSS 13 programos versiją. Pateikiamas rodiklių pasiskirstymas absoliučiais skaičiais ir procentais, apskaičiuotas chi kvadratas (Chi-kv.). Sirtumas statistiškai reikšmingas kai pasikliovimo lygmuo p<0,05. Atlikta mokslinių straipsnių, sveikatos sistemos teisinės ir normatyvinės medžiagos ir t.t., analizė. Gautos šios išvados: įvertinus bendrą žinių lygį tarp apklaustų respondentų, galima teigti, kad gydytojai radiologai ir radiologijos laborantai pakankamai gerai žino radiacinės saugos principus bei apšvitos keliamą pavojų. Tačiau atliktas tyrimas taip pat parodė, kad jiems vis dar trūksta žinių kai kuriais specifiniais klausimais, pavyzdžiui tokiais kaip tipinės efektinės dozės gaunamos atliekant įvairias procedūras... [toliau žr. visą tekstą] / Main task – to estimate and evaluate medical personnel’s of health care (doctors of radiology and radiology assistants) informativeness about receivable irradiance towards patients and radiational safety in city of Vilnius. Object of research - doctors of radiology and radiology assistants. During this research 140 respondents were questioned from 15 health care institutions. Overall 35 radiologists were questioned (15 men and 20 women), 105 radiology assistants (4 men and 101 women) and that’s accordingly 20, 0% and 75, 0%. Age variance of the respondents is from 23 up to 71 years old (average of 47.43 years old). Descriptive research type and survey was used in order to achieve the goals of this research. Statistical data analysis was performed by using SPSS program, version 13. The given distribution of index is in natural numbers and in percentage, Chi-square is counted (Chi-sq). Statistically the difference is meaningful when the level of probability is p<0,05. The analysis of science articles, law normative materials, health care systems, etc. was accomplished. The conclusion: after the evaluation of knowledge of the respondents it is clear that, doctors of radiology and radiology assistants have enough knowledge about radiational safety and dangers of irradiance. The research also revealed that they do not have enough knowledge concerning the specific topics, for example the doses that are received during variable procedures, the dependence of the dose, the observation... [to full text]