21 resultados para ambiguity aversion
em Digital Commons at Florida International University
Resumo:
My dissertation consists of three essays. The central theme of these essays is the psychological factors and biases that affect the portfolio allocation decision. The first essay entitled, “Are women more risk-averse than men?” examines the gender difference in risk aversion as revealed by actual investment choices. Using a sample that controls for biases in the level of education and finance knowledge, there is evidence that when individuals have the same level of education, irrespective of their knowledge of finance, women are no more risk-averse than their male counterparts. However, the gender-risk aversion relation is also a function of age, income, wealth, marital status, race/ethnicity and the number of children in the household. The second essay entitled, “Can diversification be learned ?” investigates if investors who have superior investment knowledge are more likely to actively seek diversification benefits and are less prone to allocation biases. Results of cross-sectional analyses suggest that knowledge of finance increases the likelihood that an investor will efficiently allocate his direct investments across the major asset classes; invest in foreign assets; and hold a diversified equity portfolio. However, there is no evidence that investors who are more financially sophisticated make superior allocation decisions in their retirement savings. The final essay entitled, “The demographics of non-participation ”, examines the factors that affect the decision not to hold stocks. The results of probit regression models indicate that when individuals are highly educated, the decision to not participate in the stock market is less related to demographic factors. In particular, when individuals have attained at least a college degree and have advanced knowledge of finance, they are significantly more likely to invest in equities either directly or indirectly through mutual funds or their retirement savings. There is also evidence that the decision not to hold stocks is motivated by short-term market expectations and the most recent investment experience. The findings of these essays should increase the body of research that seeks to reconcile what investors actually do (positive theory) with what traditional theories of finance predict that investors should do (normative theory).
Resumo:
My dissertation consists of three essays. The central theme of these essays is the psychological factors and biases that affect the portfolio allocation decision. The first essay entitled, “Are women more risk-averse than men?” examines the gender difference in risk aversion as revealed by actual investment choices. Using a sample that controls for biases in the level of education and finance knowledge, there is evidence that when individuals have the same level of education, irrespective of their knowledge of finance, women are no more risk-averse than their male counterparts. However, the gender-risk aversion relation is also a function of age, income, wealth, marital status, race/ethnicity and the number of children in the household. The second essay entitled, “Can diversification be learned?” investigates if investors who have superior investment knowledge are more likely to actively seek diversification benefits and are less prone to allocation biases. Results of cross-sectional analyses suggest that knowledge of finance increases the likelihood that an investor will efficiently allocate his direct investments across the major asset classes; invest in foreign assets; and hold a diversified equity portfolio. However, there is no evidence that investors who are more financially sophisticated make superior allocation decisions in their retirement savings. The final essay entitled, “The demographics of non-participation”, examines the factors that affect the decision not to hold stocks. The results of probit regression models indicate that when individuals are highly educated, the decision to not participate in the stock market is less related to demographic factors. In particular, when individuals have attained at least a college degree and have advanced knowledge of finance, they are significantly more likely to invest in equities either directly or indirectly through mutual funds or their retirement savings. There is also evidence that the decision not to hold stocks is motivated by short-term market expectations and the most recent investment experience. The findings of these essays should increase the body of research that seeks to reconcile what investors actually do (positive theory) with what traditional theories of finance predict that investors should do (normative theory).
Resumo:
This dissertation examines one category of international capital flows, private portfolio investments (private refers to the source of capital). There is an overall lack of a coherent and consistent definition of foreign portfolio investment. We clarify these definitional issues.^ Two main questions that pertain to private foreign portfolio investments (FPI) are explored. The first problem is the phenomenon of home preference, often referred to as home bias. Related to this are the observed cross-investment flows between countries that seem to contradict the textbook rendition of private FPI. A description of the theories purporting to resolve the home preference puzzle (and the cross-investment one) are summarized and evaluated. Most of this literature considers investors from major developed countries. I consider--as well--whether investors in less developed countries have home preference.^ The dissertation shows that home preference is indeed pervasive and profound across countries, in both developed and emerging markets. For the U.S., I examine home bias in both equity and bond holdings as well. I find that home bias is greater when we look at equity and bond holdings than equity holdings solely.^ In this dissertation a model is developed to explain home bias. This model is original and fills a gap in the literature as there have been no satisfactory models that handle at the same time both home preference and cross-border holdings in the context of information asymmetries. This model reflects what we see in the data and permits us to reach certain results by the use of comparative statics methods. The model suggests, counter-intuitively, that as the rate of return in a country relative to the world rate of return increases, home preference decreases. In the context of our relatively simple model we ascribe this result to the higher variance of the now higher return for home assets. We also find, this time as intended, that as risk aversion increases, investors diversify further so that home preference decreases.^ The second question that the dissertation deals with is the volatility of private foreign portfolio investment. Countries that are recipients of these flows have been wary of such flows because of their perceived volatility. Often the contrast is made with the perceived absence of volatility in foreign direct investment flows. I analyze the validity of these concerns using first net flow data and then gross flow data. The results show that FPI is not, in relative terms, more volatile than other flows in our sample of eight countries (half were developed countries and the rest were emerging markets).^ The implication therefore is that restricting FPI flows may be harmful in the sense that private capital may not be allocated efficiently worldwide to the detriment of capital poor economies. More to the point, any such restrictions would in fact be misguided. ^
Resumo:
The purpose of this dissertation was to analyze the works of Federico García Lorca within the mystic context that dominates their very genesis. The problematic definition of mysticism was explored lest it be confused with traditional mysticism, which implies union with the divine. The historiography of literature speaks of the Mystic Genre, yet it does not address the mystic mode of artistic creation due to its inability to adhere to rational measure. This mode of conception was explored through Lorca's poetic discourse: ‘Lorquian mysticism’ is the result of the poet's cultivation of an innate spiritual potential enhanced by external influences and technical mastery. ^ There is visible influence of Fray Luis of León in Lorca's early Libro de poemas and El maleficio de la mariposa, as well as of Saint John of the Cross in the later Diván del Tamarit, Sonetos de amor and Yerma. However, definitive echoes of poets from the Sufi and other Eastern mystic traditions were also illustrated in these late works. A persistent longing to elide the physical condition, the greatest obstacle of the transcendental quest, is the essence of Lorca's poetic voice. ^ The object of this analysis was Lorca's language, which reaches levels removed from conventional thought. His dazzling metaphors and his particular use of symbols and of paradox compare equitably with those of great mystic poets. Like them, Lorca was faced with the same limitations of language to describe an ineffable experience; he embraced what Octavio Paz describes as ‘sacred language’: there is a linguistic frugality as well as an ambiguity in Lorca's poetic art that result from his realization of supercognitive states. Yet such an interpretation is rejected by the rationalist approach, invoking the age-old debate between faith and reason and signaling the application of psychoanalytical theory. This limited approach was disputed on the basis of reader-response theory. Lorca was truly an eclectic and a modification of the conventional reader's preestablished horizon of expectations is essential in order to seal the gaps in his late works. This innovative perspective placed Lorca within the framework of a new mysticism in the modern world. ^
Resumo:
This study focuses on empirical investigations and seeks implications by utilizing three different methodologies to test various aspects of trader behavior. The first methodology utilizes Prospect Theory to determine trader behavior during periods of extreme wealth contracting periods. Secondly, a threshold model to examine the sentiment variable is formulated and thirdly a study is made of the contagion effect and trader behavior. ^ The connection between consumers' sense of financial well-being or sentiment and stock market performance has been studied at length. However, without data on actual versus experimental performance, implications based on this relationship are meaningless. The empirical agenda included examining a proprietary file of daily trader activities over a five-year period. Overall, during periods of extreme wealth altering conditions, traders "satisfice" rather than choose the "best" alternative. A trader's degree of loss aversion depends on his/her prior investment performance. A model that explains the behavior of traders during periods of turmoil is developed. Prospect Theory and the data file influenced the design of the model. ^ Additional research included testing a model that permitted the data to signal the crisis through a threshold model. The third empirical study sought to investigate the existence of contagion caused by declining global wealth effects using evidence from the mining industry in Canada. Contagion, where a financial crisis begins locally and subsequently spreads elsewhere, has been studied in terms of correlations among similar regions. The results provide support for Prospect Theory in two out of the three empirical studies. ^ The dissertation emphasizes the need for specifying precise, testable models of investors' expectations by providing tools to identify paradoxical behavior patterns. True enhancements in this field must include empirical research utilizing reliable data sources to mitigate data mining problems and allow researchers to distinguish between expectations-based and risk-based explanations of behavior. Through this type of research, it may be possible to systematically exploit "irrational" market behavior. ^
Resumo:
With the rapid growth of the Internet, computer attacks are increasing at a fast pace and can easily cause millions of dollar in damage to an organization. Detecting these attacks is an important issue of computer security. There are many types of attacks and they fall into four main categories, Denial of Service (DoS) attacks, Probe, User to Root (U2R) attacks, and Remote to Local (R2L) attacks. Within these categories, DoS and Probe attacks continuously show up with greater frequency in a short period of time when they attack systems. They are different from the normal traffic data and can be easily separated from normal activities. On the contrary, U2R and R2L attacks are embedded in the data portions of the packets and normally involve only a single connection. It becomes difficult to achieve satisfactory detection accuracy for detecting these two attacks. Therefore, we focus on studying the ambiguity problem between normal activities and U2R/R2L attacks. The goal is to build a detection system that can accurately and quickly detect these two attacks. In this dissertation, we design a two-phase intrusion detection approach. In the first phase, a correlation-based feature selection algorithm is proposed to advance the speed of detection. Features with poor prediction ability for the signatures of attacks and features inter-correlated with one or more other features are considered redundant. Such features are removed and only indispensable information about the original feature space remains. In the second phase, we develop an ensemble intrusion detection system to achieve accurate detection performance. The proposed method includes multiple feature selecting intrusion detectors and a data mining intrusion detector. The former ones consist of a set of detectors, and each of them uses a fuzzy clustering technique and belief theory to solve the ambiguity problem. The latter one applies data mining technique to automatically extract computer users’ normal behavior from training network traffic data. The final decision is a combination of the outputs of feature selecting and data mining detectors. The experimental results indicate that our ensemble approach not only significantly reduces the detection time but also effectively detect U2R and R2L attacks that contain degrees of ambiguous information.
Resumo:
Since 2000, the number of living wage ordinances has steadily increased throughout the country. While most of the current research has focused on the beneficial outcomes of living wages, little has been published on their administrative practices. To address this shortcoming, this study focused on the identification of key administrative and political factors involved impacting the implementation of living wage ordinances in Miami-Dade and Broward Counties. The study utilized a triangulation of interviews, surveys, and direct observation. The author conducted interviews of administrators and members of the living wage oversight boards in both counties and observed the monthly meetings held by each county's oversight board from January 2006 to June 2007. These findings were buttressed with a national survey of senior staff in other living wage communities. The study utilized descriptive statistics, Chi Square, Cronbach's Alpha, and Spearman's Rank Correlation Coefficient (Spearman's rho). Interviews indicated that administrators in Dade and Broward are seriously under-staffed and budgeted. Ambiguities in the enabling ordinances have lead to loopholes that undermine implementation and accountability for participating contractors. Survey results showed that policy ambiguity, organizational politics, and a lack of organizational capacity were significant negative factors in the implementation process while an organizational culture emphasizing consistent enforcement was a positive factor. Without the proper inputs, an organization hinders itself from meeting its outputs and outcomes. This study finds that Broward and Miami-Dade Counties do not provide the necessary administrative support to implement a living wage effectively – in stark contrast to the high hopes and strong political support behind their passage. For a living wage to succeed, it first needs an organizational culture committed to providing the necessary resources for implementation as well as transparent, consistent accountability mechanisms.
Resumo:
In this dissertation, I investigate three related topics on asset pricing: the consumption-based asset pricing under long-run risks and fat tails, the pricing of VIX (CBOE Volatility Index) options and the market price of risk embedded in stock returns and stock options. These three topics are fully explored in Chapter II through IV. Chapter V summarizes the main conclusions. In Chapter II, I explore the effects of fat tails on the equilibrium implications of the long run risks model of asset pricing by introducing innovations with dampened power law to consumption and dividends growth processes. I estimate the structural parameters of the proposed model by maximum likelihood. I find that the stochastic volatility model with fat tails can, without resorting to high risk aversion, generate implied risk premium, expected risk free rate and their volatilities comparable to the magnitudes observed in data. In Chapter III, I examine the pricing performance of VIX option models. The contention that simpler-is-better is supported by the empirical evidence using actual VIX option market data. I find that no model has small pricing errors over the entire range of strike prices and times to expiration. In general, Whaley’s Black-like option model produces the best overall results, supporting the simpler-is-better contention. However, the Whaley model does under/overprice out-of-the-money call/put VIX options, which is contrary to the behavior of stock index option pricing models. In Chapter IV, I explore risk pricing through a model of time-changed Lvy processes based on the joint evidence from individual stock options and underlying stocks. I specify a pricing kernel that prices idiosyncratic and systematic risks. This approach to examining risk premia on stocks deviates from existing studies. The empirical results show that the market pays positive premia for idiosyncratic and market jump-diffusion risk, and idiosyncratic volatility risk. However, there is no consensus on the premium for market volatility risk. It can be positive or negative. The positive premium on idiosyncratic risk runs contrary to the implications of traditional capital asset pricing theory.
Resumo:
Polynomial phase modulated (PPM) signals have been shown to provide improved error rate performance with respect to conventional modulation formats under additive white Gaussian noise and fading channels in single-input single-output (SISO) communication systems. In this dissertation, systems with two and four transmit antennas using PPM signals were presented. In both cases we employed full-rate space-time block codes in order to take advantage of the multipath channel. For two transmit antennas, we used the orthogonal space-time block code (OSTBC) proposed by Alamouti and performed symbol-wise decoding by estimating the phase coefficients of the PPM signal using three different methods: maximum-likelihood (ML), sub-optimal ML (S-ML) and the high-order ambiguity function (HAF). In the case of four transmit antennas, we used the full-rate quasi-OSTBC (QOSTBC) proposed by Jafarkhani. However, in order to ensure the best error rate performance, PPM signals were selected such as to maximize the QOSTBC’s minimum coding gain distance (CGD). Since this method does not always provide a unique solution, an additional criterion known as maximum channel interference coefficient (CIC) was proposed. Through Monte Carlo simulations it was shown that by using QOSTBCs along with the properly selected PPM constellations based on the CGD and CIC criteria, full diversity in flat fading channels and thus, low BER at high signal-to-noise ratios (SNR) can be ensured. Lastly, the performance of symbol-wise decoding for QOSTBCs was evaluated. In this case a quasi zero-forcing method was used to decouple the received signal and it was shown that although this technique reduces the decoding complexity of the system, there is a penalty to be paid in terms of error rate performance at high SNRs.
Resumo:
The purpose of this qualitative case study was to gain insight into the perspectives of experienced higher education administrators regarding faculty unionization, the collective bargaining process, and the interpersonal relationships between higher education faculty members and administrators. ^ The primary method of data collection was semi-structured face to face interviews with nine administrators from two community colleges and two universities in the south Florida area. All of the study participants worked with unionized faculty members and had direct experience participating in bargaining negotiations. ^ Upon the completion of each interview, the researcher listened to the taped audio recording of the interview several times and then transcribed all of the information from the audiotape into a Word file. Data collection and analysis for each participant were performed concurrently. Using a modified concept mapping approach, the research questions were written on large yellow sticky notes and placed in the middle of a wall in the researcher’s home with nine descriptive categorical themes written on smaller sticky notes placed around the study questions. The highlighted quotes and key phrases were cut from each transcript and placed under each of the descriptive categories. Over the course of a few months repeatedly reviewing the research questions that guided this study, the theory of symbolic interactionism, and relevant literature the categorical descriptive themes were refined and condensed into five descriptive themes. ^ Study findings indicated that the administrators: (a) must have a clear understanding of what it is that the faculty does to be an effective representative at the bargaining table, (b) experienced role ambiguity and role strain related to a lack of understanding as to their role at the bargaining table and a lack of organizational support, (c) were not offered any type of training in preparation for bargaining, (d) perceived a definite “us versus them” mentality between faculty and administration, and (e) saw faculty collective bargaining at public institutions of higher education in Florida as ineffectual. ^
Resumo:
The South American electric knifefish, Brachyhypopomus gauderio, uses weakly electric fields to see and communicate in the dark. Only one study to date has investigated natural behavior in this species during the breeding season; this study proposed that B. guarerio has an exploded lek polygyny breeding system. To test this hypothesis, artificial marshes simulating the native vegetation, temperature, and water conductivities of the South American subtropics were created to study seasonal variation in associative behavior of B. gauderio during the breeding and non-breeding seasons. Mark/recapture methods were used to keep track of individual fish and their dispersion inside the experimental designs. The experimental design proved to be extremely successful at eliciting reproduction. Differences were found in seasonal variations of social behaviors between adult and juvenile populations. Although no apparent sex. differences in movement patterns were found during the breeding season; a trend for male-male aversion was found, suggesting male-male avoidance as a possible strategy guiding aspects of social behaviors in this species. Further, movement may be a tactic for mate seeking as the individuals who moved the most during the breeding season obtained the most opposite sex interactions. These findings support the exploded lek polygyny model. Social interactions are subject to complex regulation by social, physiologic and ecological factors; the extent to which these associations are repeatable may provide novel insights on the evolution of sociality as it has been shaped by natural selection.
Resumo:
The purpose of this study is to investigate supervisory support as a moderator of the effects of role conflict and role ambiguity on emotional exhaustion and job satisfaction. This study also examines the moderating role of supervisory support on the relationship between emotional exhaustion and job satisfaction. Data were collected from a sample of frontline hotel employees in Northern Cyprus. The aforementioned relationships were tested based on hierarchical multiple regression analysis. The results demonstrate that supervisory support mitigates the impact of role conflict on emotional exhaustion and further reveal that supervisory support reduces the effect of emotional exhaustion on job satisfaction. There is no empirical support for the rest of the hypothesized relationships. Implications of the empirical results are discussed, and future research directions are offered.
Resumo:
The purpose of this study is to determine the potential impact of selected organizational factors on boundary-spanning-role employees’ perceptions of service recovery performance. This study also aims to assess the impact of service recovery performance on the intention to leave the job and extrinsic job satisfaction. This study uses a sample of frontline employees in Belek, Antalya, Turkey. The empirical findings revealed that education, team work and role ambiguity as frontline job perceptions were found to exert positive influences on the service recovery performance, but, empowerment, reward, and organizational commitment were found to have negative effects on the service recovery performance.
Resumo:
The first part of the study examined the effect of industry risk changes on perceived audit risk at the financial statement level and whether these changes depended on individual differences such as experience and tolerance for ambiguity. ^ Forty-eight auditors from two offices of one of the “Big 5” CPA firms participated in this study. The ANOVA results supported the effect of industry risk in the assessment of audit risk at the financial statement level. Higher industry risk was associated with higher perceived audit risk. Tolerance for ambiguity was also significant in explaining the changes in the assessment of audit risk. Auditors with a high tolerance for ambiguity perceived lower audit risk than auditors with a low tolerance for ambiguity. Although ANOVA results did not find experience to be significant, a t-test for experience showed it to be marginally significant and inversely related to audit risk. ^ The second part of this study examined whether differences in perceived audit risk at the financial statement level altered the extent, nature or timing of the planned auditing procedures. The results of the MANOVA suggested an overall audit risk effect at the financial statement level. Perceived audit risk was significant in explaining the variation in the number of hours planned for the total cycle and the number of hours p1anned for the tests of balances and details. Perceived audit risk was not significant in determining the analytical review procedures planned, but assessed inherent risk at the cycle level was significant. The higher the inherent risk the more analytical procedures were planned. Perceived audit risk was not significant in explaining the timing of the procedures, but individual differences were significant. The results showed that experienced auditors and those with a high tolerance for ambiguity were less likely to postpone the performance of the interim procedures or the time at which the majority of audit work would be done. ^
Resumo:
Carbon capture and storage (CCS) can contribute significantly to addressing the global greenhouse gas (GHG) emissions problem. Despite widespread political support, CCS remains unknown to the general public. Public perception researchers have found that, when asked, the public is relatively unfamiliar with CCS yet many individuals voice specific safety concerns regarding the technology. We believe this leads many stakeholders conflate CCS with the better-known and more visible technology hydraulic fracturing (fracking). We support this with content analysis of media coverage, web analytics, and public lobbying records. Furthermore, we present results from a survey of United States residents. This first-of-its-kind survey assessed participants’ knowledge, opinions and support of CCS and fracking technologies. The survey showed that participants had more knowledge of fracking than CCS, and that knowledge of fracking made participants less willing to support CCS projects. Additionally, it showed that participants viewed the two technologies as having similar risks and similar risk intensities. In the CCS stakeholder literature, judgment and decision-making (JDM) frameworks are noticeably absent, and public perception is not discussed using any cognitive biases as a way of understanding or explaining irrational decisions, yet these survey results show evidence of both anchoring bias and the ambiguity effect. Public acceptance of CCS is essential for a national low-carbon future plan. In conclusion, we propose changes in communications and incentives as programs to increase support of CCS.