Miracle-dz/UniFAR-FTUs huggingface dataset:
Essays on an emerging stock market: the case of Nairobi stock exchange (Statistical distribution of returns, market seasonality and reactions to dividend announcements

The general objective of this thesis is to test the well known market efficiency hypothesis using daily data from the Nairobi Stock Exchange. This high frequency data permits a thorough testing of the efficiency hypothesis because the very shortperiod nature of the data, helps control for elfects of other determinants of the stock market performance, which have been a persistent problem in previous studies. The analysis of data reveals that the distribution of daily compounded returns on ordinary shares is not normal, and unlike what some previous studies have shown, the distribution of stock returns exhibits long tails. The shape of this distribution implies that the actual data fluctuates with a bigger margin than what would otherwise be expected from a standard normal distribution. It also renders linear models unsuitable tools for analyzing behavior of stock returns. There is strong evidence of volatility, clustering, and asymmetry of price dispersion, which further justifies the use of non­ linear models in the analysis of stock markets. With regard to asymmetry, it is found that big changes in returns follow big ones, and that small changes follow small ones, and negative changes in returns are more persistent than positive changes. On asset pricing models, the results show that the linear model fails to capture the relationship between daily returns on ordinary shares and market returns. As consistent with previous studies, there is evidence of ARCH effect, with TGARCH model outperforming the OLS, GARCH (1, 1) and the EGARCH models. On calendar anomalies, the study shows that though methodologies play an important role in outcomes of tests of the null of the market efficiency hypothesis, the various methods deliver similar trends, such that the calendar effect is only evident when large periods are considered. The implication of this is that though there is no evidence of day-of-the-week effect, there is a weak pointer towards existence of month-of-the-year effect, and strong evidence of quarter-of-the-year effect. The
Covariance in parasite burdens: the effect of predisposition to infection

Summary Recently the phenomenon of predisposition to helminth infection has been reported in a number of studies: those individuals which are heavily infected before treatment with an anthelmintic tend also to acquire heavy parasite burdens following a period of reinfection. This correlation between parasite burdens in initial and reinfections is generated by differences between hosts in their exposure to infective stages and in their susceptibility to infection. Inter-host differences in these factors also generate the aggregated or over-dispersed parasite distributions that are usually observed. This paper uses probability theory to predict the correlation between initial and reinfection parasite burdens assuming that those inter-host differences which generate over-dispersion remain constant for a given individual between initial and reinfection periods. The predicted correlation is considerably greater than is observed in most published data sets. Over-dispersion is thus generated by variability between hosts which has components that remain constant between initial and reinfection and also components which vary between infection periods. The model is modified to account for those two sources of variability, and the result applied to published data to determine the contributions made by short and long-term factors to the observed distributions.
Mirroring emotion system - on-line synthesizing facial expressions on a robot face

Social skills are an important issue throughout human life. Therefore, systems that can synthesize emotions, for example virtual characters (avatars) and robotic platforms, are gaining special attention in the literature. In particular, those systems may be important tools in order to promote social and emotional competences in children (or adults) that have some communication/interaction impairments. The present paper proposes a mirroring emotion system that uses the recent Intel RealSense 3D sensor along with a humanoid robot. The system extracts the user's facial Action Units (AUs) and head motion data. Then, it sends the information to the robot allowing on-line imitation. The first tests were conducted in a laboratorial environment using the software FaceReader in order to verify its correct functioning. Next, a perceptual study was performed to verify the similarity between the expressions of a performer and those of the robot using a quiz distributed to 59 respondents. Finally, the system was evaluated with typically developing children with 6 to 9 years old. The robot mimicked the children's emotional facial expressions. The results point out that the present system can on-line and accurately map facial expressions of a user onto the robot.
DOES CORPORATE SOCIAL RESPONSIBILITY ENHANCE TRUST AND QUALITY OF WORK LIFE OF WORKERS

In recent decades, corporate social responsibility has emerged as a crucial goal in business. Several researchers have agreed that it is a win-win business strategy which contributes to the financial well-being of the firm. However, the question of how corporate social responsibility contributes to the well-being of workers is still unanswered, especially in transitioning markets like Vietnam. Realizing this role of corporate social responsibility in business, this study investigates the impact of corporate social responsibility on both trust in organization and quality of work life of workers in Vietnam. Based on a data set collected from 501 employees working for various firms in Ho Chi Minh City, Vietnam, the study finds that corporate social responsibility directly and indirectly (mediated by trust in organization) enhances quality of work life of workers. The findings of the study suggest that the government and management should pay close attention to corporate social responsibility and make efforts to communicate its corporate social responsibility mission and activities to their employees.
Influence of genes, nevi, and sun sensitivity on melanoma risk in a family sample unselected by family history and in melanoma-prone families.

BACKGROUND Few family studies have investigated the effects of genetic, environmental, and host factors on melanoma risk, and most have been restricted to high-risk families. We assessed the role of these factors on melanoma risk in two types of families: families ascertained through melanoma probands but unselected by family history and melanoma-prone families. METHODS Data on pigmentary traits, nevus phenotypes, exposure to sun, and reactions to sunlight were collected from 295 families unselected by family history and 53 melanoma-prone families. We modeled melanoma risk using a logistic regressive model incorporating the effect of a melanoma-predisposing gene, familial dependence, and potential risk factors (e.g., pigmentary traits, nevus phenotypes, history of sun exposure, skin reactions to sunlight). Maximum-likelihood estimates of the parameters of the regressive model were used to compute odds ratios associated with each risk factor and age-specific melanoma risk depending on the genotype at the melanoma-predisposing gene and the effects of risk factors. All statistical tests were two-sided. RESULTS In the families unselected by family history, there was statistically significant evidence (P<.001) for a dominant gene, with melanoma risk reaching 0.49 and 0.67 by age 80 years in male and female gene carriers, respectively. Melanoma risk was statistically significantly influenced by total nevi (odds ratio of hazard function [OR] = 5.81, 95% confidence interval [CI] = 3.47 to 8.99), sun exposure (OR = 5.37, 95% CI = 4.44 to 6.36), and sunburn interacting with the gene (OR = 26.31, 95% CI = 7.56 to 99.22 in gene carriers and OR = 1.67, 95% CI = 1.36 to 2.03 in noncarriers). Twenty of the 53 melanoma-prone families had cosegregating mutations in CDKN2A, a gene known to be associated with melanoma. In these 53 families, three risk factors in addition to CDKN2A mutations increased melanoma risk: dysplastic nevi (OR = 2.32, 95% CI = 2.08 to 2.58), total nevi (OR = 1.99, 95% CI = 1.61 to 2.20) and sunburn (OR = 5.16, 95% CI = 4.82 to 5.52). CONCLUSIONS Together, a melanoma-predisposing gene (identified as being CDKN2A in melanoma-prone families), number of nevi and/or dysplastic nevi, and sun-related covariates influence melanoma risk in both families unselected by family history and melanoma-prone families.
Linking data-rich environments with service innovation in incumbent firms: a conceptual framework and research propositions

The impact of big data on innovation is not only driven by technology and analytics. It involves a transformation of the organizational culture, structures, processes, roles and capabilities that underpin the innovation process. Understanding these factors is particularly important for service innovators, given the strong interdependence between the organizational context and technology in service companies. Moreover, in many of these organizations, the innovation process is still deeply rooted in a non-digital past. This study answers the call to understand what are the key characteristics of a systematic process for service innovation in data-rich environments. In particular, the authors investigate the primary factors that enable existing service organizations to capture the innovation potential inherent in data-rich environments. To this aim, a two-step research design is implemented. First, the service innovation and information systems literatures are integrated in a unified conceptual framework that articulates the relationship between data-rich environments and service innovation from an organizational perspective. Second, the authors carry out 40 semi-structured interviews in seven large service firms, which allow them to refine and populate the initial framework with typologies, concepts, and examples from the field. A major contribution of this study is to articulate the concept of data density, as three distinct processes (pattern spotting, real-time decisioning and synergistic exploration) connecting data-rich environments with service innovation opportunities. Finally, the authors identify a set of organizational enablers that facilitate the links between technology, data density processes, and service innovation. The findings of this study offer a roadmap for service managers who need to align the service innovation process of their organizations with the opportunities offered by data-rich environments.
Uniformly introreducible sets

Retraceable sets were denned in Dekker and Myhill [5]. In that paper it was pointed out that if A is a retraceable set, then A is recursive in each of its infinite subsets, i.e. A is introreducible. We would like to know to what extent theorems on retraceable sets also hold for introreducible sets; however, we have made very little progress in this direction. On the other hand, “uniformly introreducible” sets (which will be defined in §2) are more tractable, and it turns out that some results on retraceable sets extend to uniformly introreducible sets while others fail.
Three Essays on Corporate Bond Market Liquidity

The transactions database TRACE is rapidly becoming the standard data source for empirical research on US corporate bonds. This paper is the first to thoroughly discuss the assumptions needed to clean the disseminated TRACE data and to suggest that different filters should be used depending upon the application. 7.7% of all reports in TRACE are errors and in some cases up to 18% of the reports should be deleted. Failing to correct for these errors will bias popular liquidity measures towards a more liquid market. The median bias for the daily turnover will be 7.4% and for a quarter of the bonds the Amihud price impact measure will be underestimated by at least 14.6%. Further, calculating these two measures on the same data sample would potentially bias one of them. This paper has been published in the Journal of Fixed Income 19(2), 2009. I would like to thank Marti Subrahmanyam, Raghu Sundaram, Peter Feldhütter, David Lando, and participants in the ”Seminar in Derivatives” at Stern School of Business. All errors are my responsibility.
LEDFD: A Low Energy Consumption Distributed Fault Detection Algorithm for Wireless Sensor Networks

Detection of faulty nodes and network energy saving have become the hottest research topics. Furthermore, current fault detection algorithms always pursue high detection performance but neglect energy consumption. In order to obtain good fault detection performance and save the network power, this paper proposes a low energy consumption distributed fault detection algorithm (LEDFD), which takes full advantage of temporally correlated and spatially correlated characteristics of the sensor nodes. LEDFD utilizes the temporally correlated information to examine some faulty nodes and then utilizes the spatially correlated information to examine the nodes that have not been detected as faulty through exchanging information among neighbor nodes to determine those nodes' state. Because LEDFD takes the data produced by nodes themselves to detect certain types of faults, which means nodes need not exchange information with their neighbor nodes during the entire detection process, the energy consumption of networks is efficiently reduced. Experimental results show that the algorithm has good performance and low energy consumption compared with current algorithms.
Impacts of Wire Basket Retention and Removal on Planting Time, Root-Ball Condition, and Early Growth of Acer platanoides and Gleditsia triacanthos var. inermis

The use of wire baskets to maintain root-ball integrity has greatly increased the efficiency of balled-and-burlapped har-vesting practices. Despite the advantages offered by these products, there is notable disagreement among green industry groups and practitioners regarding the effects of wire basket retention or removal at the time of planting. For this experiment, 30 Norway maple ( Acer platanoides ) and 30 honeylocust ( Gleditsia triacanthos var. inermis ‘Skycole’) shade trees were evenly planted at two sites in the midwestern U.S. after random assignment of a wire-basket removal treatment (i.e., no removal/intact, partial removal, and full removal). Planting time and initial root-ball condition were assessed at the time of installation. Short-term growth and plant stress were assessed each season as trees became established in the research plots. Results indicate that treatment impacted both planting time ( P < 0.0001; both sites) and root-ball condition ( P = 0.0360 or P = 0.0049; depending on site). In contrast, treatment had limited impact on tree caliper, twig elongation, or chlorophyll fluorescence in the first two to three years after planting.
Determinants of Profitability: Evidence from Power and Energy Sector

Abstract The study examines the impact of key determinants of profitability of power and energy sector in Pakistan such as firm size, firm age, firm growth, productivity, financial leverage and electricity crisis discussed in the broader inter-disciplinary literature. For this purpose panel data of 16 firms of power and energy sector is taken for 2001 to 2012. The study considers profitability determinants at the firm as well as industry affiliation levels in examining hypotheses developed from resource-based approaches. Random effect model is used to detect the combination of variables that best estimated the impact of the explanatory variables on the dependent variable. The empirical results suggest that firm size, firm growth, and electricity crisis positively impact the profitability. However, firm age, financial leverage and productivity negatively influence the firm profitability. This study also propose that during the electricity crisis the profitability of power sector is increased even production of this sector is very low. The findings further indicate that larger and younger firms with high growth and low productivity are more likely to be profitable. This study has found that firm productivity and firm size are the strongest determinants of profitability in power and energy sector of Pakistan.
When is Likely Unlikely: Investigating the Variability of Vagueness

An important part of explaining how people communicate is to understand how people relate language to entities in the world. In describing measurements, people prefer to use qualitative words like ‘tall’ without precise applicability conditions, also known as vague words. The use of vague language varies widely across contexts, individuals, and tasks (single reference vs. comparisons between targets), but despite this variability, is used quite successfully. A potential strategy for using vague language is to leverage the set of alternative descriptors to settle on the best option. To determine whether people use this strategy, we conducted an experiment where participants picked vague words from sets of alternatives to describe either probability or color values. We varied the set of alternatives from which participants could choose. Empirical evidence supports the hypothesis that people use the set of available options to pick vague descriptors. The theoretical implications of this work are discussed.
Effects of temperature on water tree initiation and propagation at equivalent AC frequency

Water treeing occurs when an ac voltage is applied to an electrical insulation system such as those in power cables and power apparatus. From a practical viewpoint, research on water treeing has mostly been performed under the application of a high-frequency ac voltage. However, in recent years, power cables and power apparatus have also been used under dc voltage application owing to progress in inverter technology. The use of rotating electrical machines with an inverter has become widespread owing to their contribution to the prevention of global warming, high effectiveness and the reduced maintenance required. In an underwater motor driven by the voltage of an inverter, it is necessary to consider the water treeing of the motor insulation and the cable insulation connected to the drive board. Up to now, we have performed accelerated deterioration tests at the inverter carrier frequency of 500Hz. However, in the case of an inverter waveform, an accelerated deterioration test cannot be performed because the inverter waveform becomes markedly different from that of an actual machine when the basic frequency is increased. In this paper, we report the development of a new water electrode test method and the investigation of the effects of temperature on water tree initiation and propagation utilizing an equivalent ac frequency of 50Hz. We found that a water tree was initiated within two weeks even at the basic frequency of 50Hz. Furthermore, we compared the test results obtained at 500Hz and 50Hz at different temperatures.
A case report of Intestinal Lymphangiectasia

This is the case report of a 7 month old child from Yopal with intestinal lymphangiectasia who was sent to Bogota. We also review the issue of intestinal lymphangiectasia, a rare disease involving intestinal lymphatic vessels which caused hypoproteinemia, edema, ascites and protein-losing enteropathy.
Liver stiffness and platelet count for identifying patients with compensated liver disease at low risk of variceal bleeding

The 2015 Baveno VI guidelines recommend against performing upper gastrointestinal endoscopy in patients with compensated cirrhosis who have a liver stiffness <20 kPa and a platelet count >150 000/mm³ because of a low prevalence of varices at risk of bleeding in this population. The aim was to synthesize the available evidence on the usefulness of the combined use of liver stiffness and platelet count to identify patients without oesophageal varices.
α-pyrone derivatives from a marine actinomycete Nocardiopsis sp. YIM M13066

Abstract Five new α-pyrones namely nocapyrones O-S (2–6) and nocapyrone F (1) were isolated from a deep-sea sediment strain Nocardiopsis sp. YIM M13066. Their structures were elucidated by their NMR spectroscopic data, HR-ESI-MS and crystal X-ray diffraction. Their cytotoxic activities against H1299, HeLa, HL7702, MCF-7, PC3 and U251 cell lines were evaluated.
Offender Reentry: A Mixed Model Study of Interorganizational Commitment to Partnership

This study explores the associations between the independent variables of organizational motivations and culture with the dependent variable of organizational commitment to local jail reentry partnerships. A cross-sectional, mixed methods design was used based primarily on a quantitative survey mailed to organizational informants involved in jail reentry activities within three central Florida counties. Qualitative data was also collected by observing conveniently sampled reentry meetings and analyzing the content of social artifacts, such as meeting handouts, minutes, e-mails, and other related documents. This study extends the literature by using the theoretical framework of Oliver (1990) to develop measures of organizations’ motivations (i.e., reciprocity, stability, efficiency, asymmetry, and legitimacy) to partner with jails in reentry. It also extends the literature of Fletcher, Lehman, Wexler, Melnick, Taxman, and Young (2009) by furthering the development of valid measures of interorganizational relationships. Fletcher and associates found two levels of relationships (i.e., structured and unstructured); whereas this study found that organizations are linked according to elements (i.e., linking clients, services, providers, data, program evaluation and grant funding, and management) within increasing levels of complexity. Bivariate and multivariate analyses indicated positive associations between the predictor and outcome variables, as hypothesized. However, the sample size was not large enough to determine the strength or significance between the variables. The directed content analysis of the qualitative data supported the presence of the theoretical constructs, but also indicated that they were not mutually exclusive or exhaustive. Two of the three counties ended formal reentry meetings, so a case study approach was used to analyze the three counties using
Auditory Subliminal Stimuli

The aim was to study whether stimuli that cannot be detected consciously might nevertheless influence subject’s higher cognitive functions, and whether such an effect differs in individuals with different levels of state-trait anxiety, social desirability and “Repressor”. Participants (N = 56) listened to a classical piece of music in which subliminal messages were embedded. These messages could be either positive (“I am clever”) or negative (“I am worthless”). After listening to the music participant had to complete the Standard Progressive Matrices test (Raven, Court & Raven, 1992). Levels of state and trait anxiety and social desirability were evaluated by means of questionnaires, which the subjects filled in before and after they listened to the music. Results revealed an interaction effect between social desirability and the subliminal messages for the dependent variable score on the Matrices test. Different possible explanations for the results are given; and finally suggestions for future research are recommended.