Research Doctorate - Doctor of Philosophy (PhD) / Mobile agents are programs that travel autonomously through a computer network in order to perform some computation or gather information on behalf of a human user or an application. In the last several years numerous applications of mobile agents have emerged, including e-commerce. However, mobile agent paradigm introduces a number of security threats both to the agents themselves and to the servers that they visit. This thesis gives an overview of the main security issues related to the mobile agent paradigm. The first part of the thesis focuses on security of mobile agent itself. In this part, we propose a new coupling technique based on trust as a social control to work together with existing traditional security mechanisms. It relies on the “reputation” of the hosts in the itinerary and ensures that the agent succeeds in accomplishing its task with a high probability. Due to the fact that the coupling technique requires an agent’s itinerary to be known in advance, we introduce two new concepts: a “Scout mobile agent”, whose primary purpose is to determine the itinerary required for accomplishing a given task, and a “Routed mobile agent”, which operates with an itinerary known in advance. This enables the Routed agent to incorporate various security mechanisms, including our new coupling technique. Our Routed agent technique is also applicable independently of the Scout agent, whenever the itinerary and the trust values of the platforms in the itinerary are known. We also proposed a Petrol Station as an entity that would provide a service to other entities, in the form of certifying mobile agents and equipping them with safe itinerary based on trust score and applying the Routed agent. In the second part of the thesis, we shed some light on the security of mobile agent platforms as it is considered more critical than the security of agents. In particular, we consider a scenario where a platform hosts a database containing confidential individual information and allows mobile agentstoquery the data base. This mobile agent maybe behave maliciously which is similar to an intruder in the Statistical Disclosure Control(SDC), where measuring disclosure risk is still considered as a difficult and only partly solved problem[111]. We introduce a scenario that is not adequately covered by any of the previous discloser risk measures. Shannon’s entropy can be considered a satisfactory measure for the disclosure risk that is related to the exact compromise. However, in the case of approximate compromise, we argue that Shannon’s entropy does not express precisely the intruder’s knowledge about a particular confidential value. We introduce a novel disclosure risk measure that is based on Shannon’s entropy but covers both exact and approximate compromise. The main advantage of our measure over previously proposed measures that it gives careful consideration to the attribute values in addition to the probabilities with which the values occur. We use a dynamic programming algorithm to calculate the disclosure risk for various levels of approximate compromise. Importantly, our proposed measure is independent of the applied SDC technique. Finally, we show how this measure can be used to evaluate the security mechanisms for protecting privacy in statistical databases and data mining. We conduct extensive experiments and apply our proposed security measure to three different data sets protected by three different SDC techniques, namely Sampling, Query Restriction, and Noise Addition.

<p>Company’s annual report has been widely used by stakeholders such as investors, employees, suppliers, customers and creditors. Information included in annual report consists of both mandatory information required by law, regulations as well as accounting standard and voluntary information depended on management’s judgments. We find that voluntary information vary from company to company. From corporate governance field, we find that the company’s board of directors plays an important role in monitoring the management’s performance and have an impact on management’s judgment, including their decision to disclose information in annual report. Board of directors comprises inside and independent directors. Both of them have incentives to disclose information in annual report.</p><p>In this study, we use quantitative method to examine the association between board composition and different types of voluntary disclosure in listed companies in the Shanghai stock exchange (SSE) of China and OMX Nordic Exchange Stockholm. The board composition is measured by the proportion of independent directors to total number of directors on the board. Voluntary disclosure has been classified into three categories: Strategic information, non-financial information and financial information.</p><p>The results show that there is no significant association between board composition and voluntary disclosure from our samples Chinese and Swedish companies. However, we find association between different types of voluntary disclosure and firm characteristics. We find significant negative association between strategic information and financial leverage for Chinese companies. We find significant negative association between financial information and equity-based management compensation in Swedish companies. On comparison, we find that Swedish companies is inclined to disclose more financial information than Chinese companies while Chinese companies would like to disclose more strategic information than Swedish companies.</p>

Recent research has demonstrated that high social anxiety is associated with uncertainty about one’s self views and self-concept (Moscovitch et al., 2009; Stopa et al., 2010; Wilson & Rapee, 2006). However, no research has addressed potential mechanisms underlying the link between high social anxiety and low self-certainty nor has research examined whether this relationship is bi-directional. In the current research, I propose a cyclical model in which high social anxiety leads to low self-certainty, which in turn, feeds back into higher levels of social anxiety. I also propose that the relationship between high social anxiety and low self-certainty is mediated by the self-protective self-disclosure patterns employed by socially anxious individuals. In three interconnected studies, I examine the hypothesis that social anxiety, self-disclosure and self-certainty operate in a cyclical model. Study 1 provided a correlational test of the hypothesized feedback model in its entirety and demonstrated that honesty of self-disclosure was the most important and influential mechanism underlying the link between high social anxiety and low self-certainty. Experimentally manipulating the honesty of participants’ self-disclosures in Study 2 demonstrated that dishonest self-disclosures during a social task led to low self-certainty, but only amongst individuals high in trait performance anxiety. Finally, experimentally manipulating self-certainty in Study 3 demonstrated that low self-certainty led to high anticipatory anxiety about an upcoming self-disclosure task. Together, these results elucidate a cyclical maladaptive pattern in which low self-certainty as a result of self-protective self-disclosure leads to high social anxiety and a greater reluctance to self-disclose. Results from the three studies are discussed with respect to their theoretical implications and in relation to clinical applications for individuals with social anxiety disorder.

We examine whether corporate governance affects the level of information asymmetry in the capital market. We hypothesize that firms with stronger corporate gov-ernance would be more likely to voluntarily disclose corporate information using public rather than selective methods, and that this would be associated with lower levels of in-formation asymmetry. We carefully establish the path through which corporate govern-ance affects a firms voluntary disclosure method based on previous literature. Surpris-ingly, in full sample analysis we find that firms with stronger corporate governance (as measured by Gompers et al.s, 2003, G index) are associated with higher levels of infor-mation asymmetry (as measured by Easley et al.s, 1996, PIN). In subsample analysis, we find that, consistent with our hypothesis, for the most weakly governed firms, stronger corporate governance is associated with lower information asymmetry, and the impact of corporate governance on information asymmetry is more pronounced than that of firms with moderate and strong corporate governance. <p> To further test our hypothesis, we consider the external effect of Regulation Fair Disclosure on the disclosure method to examine the corporate governance-information asymmetry relationship. Consistent with our hypothesis, our evidence suggests that by forbidding the practice of selective disclosure, the regulation significantly decreases the impact of corporate governance on information asymmetry level.

The purpose of this study was to investigate the effects of peer modeling of self-disclosure on elementary aged girls whose parents are divorced. A treatment dismantling strategy was utilized to study the effects of modeling with combinations of specific instruction and rehearsal. The primary research question was: What are the effects of peer video-tape modeling on the self-disclosure of children of divorce? Additionally, will modeling effects be significantly greater with the inclusion of specific instruction and/or rehearsal? It was hypothesized that each of the treatment groups would display significantly greater self-disclosure than would the no-treatment group. Further, it was hypothesized that modeling with specific instruction and rehearsal would yield greater disclosure than any of the other treatment groups or the no-treatment group.Twenty-two girls from grades three, four, and five received one of four treatments or no treatment. After treatment, each girl was asked to talk about her parents' divorce. The ensuing monologue became the data with which the hypotheses were evaluated.Results of the study were mixed. Modeling alone significantly influenced the length of the monologue in seconds while the three-component treatment significantly increased rate and ratio of use of personal pronouns. There was no significant difference between groups on dimension variables (i.e., type, target discloser, level of intimacy). Conclusions were drawn concerning the implications for school counselors, child psychologists, and community agencies. Modeling was viewed as a viable facilitator for increasing talk time which might lead to more "I-messages" and aid a health care giver in establishing rapport thus increasing depth of disclosure. Ramifications were considered for future research to clarify the possibilities of modeling to facilitate self-disclosure of children of divorce.

Ample evidence suggests that the behaviour of people with low self-esteem (LSEs) can lead to problems in close relationships (Wood, Hogle, & McClellan, 2009). To my knowledge, however, no research has investigated the role that perceptions of close others’ self-esteem play in undermining beneficial relationship processes. In the current paper, I propose that capitalization, a process associated with greater relationship quality (Gable, Reis, Impett, & Asher, 2004), might be hindered by the friends, partners, or family members of LSEs. In studies 1 through 3 I obtain experimental and behavioural evidence that people are reluctant to disclose their positive experiences (i.e., capitalize) when they believe the recipient has low self-esteem. In Study 4, I show the external validity of my findings with couples having real discussions. In Studies 5a and b, I examine mechanism and find that although participants have both self- and other-focused concerns regarding capitalizing with LSEs, their self-focused concerns appear to drive their behaviour. Overall, my research suggests that the perception of others’ self-esteem is a variable that guides behaviour in important social situations.

Feeling that a partner is responsive to one’s needs is crucial to intimacy (Reis, Clark, & Holmes, 2004). Just as the well-known expression, “the squeaky wheel gets the grease,” suggests that people who voice the most complaints elicit the most support from others, existing theory and research suggest that the more one expresses one’s emotions, the more one’s partners should behave responsively—with caring, understanding, and validation (Reis et al., 2004; Reis & Shaver, 1988). However, I suspected that when a person frequently expresses negativity, individual negative disclosures seem less diagnostic of true distress, and thus elicit less responsiveness from partners. Building on Biernat, Manis, and Nelson’s (1991) shifting standards model, I predicted that people use person-specific standards—taking into account the expresser’s typical (baseline) level of negative expressivity—when interpreting a close other’s negative disclosures. Results of six studies employing both correlational and experimental methods supported the hypothesis that people who frequently express negativity may have the severity of their distress underestimated and elicit less concern and responsiveness from their partners when they make negative disclosures. These findings provide insight into why even close relationship partners may fail to behave responsively to each other’s negative disclosures.

We examine whether corporate governance affects the level of information asymmetry in the capital market. We hypothesize that firms with stronger corporate gov-ernance would be more likely to voluntarily disclose corporate information using public rather than selective methods, and that this would be associated with lower levels of in-formation asymmetry. We carefully establish the path through which corporate govern-ance affects a firms voluntary disclosure method based on previous literature. Surpris-ingly, in full sample analysis we find that firms with stronger corporate governance (as measured by Gompers et al.s, 2003, G index) are associated with higher levels of infor-mation asymmetry (as measured by Easley et al.s, 1996, PIN). In subsample analysis, we find that, consistent with our hypothesis, for the most weakly governed firms, stronger corporate governance is associated with lower information asymmetry, and the impact of corporate governance on information asymmetry is more pronounced than that of firms with moderate and strong corporate governance. <p> To further test our hypothesis, we consider the external effect of Regulation Fair Disclosure on the disclosure method to examine the corporate governance-information asymmetry relationship. Consistent with our hypothesis, our evidence suggests that by forbidding the practice of selective disclosure, the regulation significantly decreases the impact of corporate governance on information asymmetry level.

Several researches asserts that as teachers are responsible for the content of teaching and by formulating teaching "Why, ""How" and "What", that will also give signals to students about what is important knowledge. This essay addresses the difficulties teachers may face in terms of self-disclosure student texts and awareness of this in the design of teaching and writing tasks. Research shows that self-disclosure and self-therapy student texts exist and that teachers are experiencing a difficulty with regard to assessment and treatment. Through qualitative interviews examined seven teachers' design of any, to the student, self-disclosure information from curriculum and policy documents. Another purpose of this paper is to examine the extent to which teachers, through the information they give to their pupils, may affect the texts students submit.   It turns out that the respondents are united in the belief that they, through their data, may affect the texts they receive from their students when they are the ones that control the content of teaching, and they agree that the curricula gives them a great choice for design data. The survey shows that the perception of the curriculum that will open up for self-disclosure texts differ as some of the respondents believe that the curriculum is very much about the students way to express feelings and opinions, while others believe that they may try to package this data in another purpose or exercise. This essay shows that there are different approaches on self-disclosure students texts, some encouraging these texts and others are trying to stay more neutral in the choice of writing topics.

Company’s annual report has been widely used by stakeholders such as investors, employees, suppliers, customers and creditors. Information included in annual report consists of both mandatory information required by law, regulations as well as accounting standard and voluntary information depended on management’s judgments. We find that voluntary information vary from company to company. From corporate governance field, we find that the company’s board of directors plays an important role in monitoring the management’s performance and have an impact on management’s judgment, including their decision to disclose information in annual report. Board of directors comprises inside and independent directors. Both of them have incentives to disclose information in annual report. In this study, we use quantitative method to examine the association between board composition and different types of voluntary disclosure in listed companies in the Shanghai stock exchange (SSE) of China and OMX Nordic Exchange Stockholm. The board composition is measured by the proportion of independent directors to total number of directors on the board. Voluntary disclosure has been classified into three categories: Strategic information, non-financial information and financial information. The results show that there is no significant association between board composition and voluntary disclosure from our samples Chinese and Swedish companies. However, we find association between different types of voluntary disclosure and firm characteristics. We find significant negative association between strategic information and financial leverage for Chinese companies. We find significant negative association between financial information and equity-based management compensation in Swedish companies. On comparison, we find that Swedish companies is inclined to disclose more financial information than Chinese companies while Chinese companies would like to disclose more strategic information than Swedish companies.