A Kreps-Scheinkman-állítás érvényessége lineáris keresletű vegyes duopóliumok esetén (The Kreps and Scheinkman result remains valid for mixed duopolies with linear demand)

Vegyes oligopóliumoknak nevezzük az olyan piacszerkezeteket, amelyek esetében a magánvállalatok mellett állami vállalatok is tevékenykednek. A vegyes oligopóliumokban az állami vállalatok részben vagy egészében a társadalmi többletet kívánják maximalizálni. Olyan vegyes duopóliumot vizsgálunk, amelyben a vállalatok előbb kiépítik kapacitásaikat, majd meghatározzák termékük kínálati árát. Kreps-Scheinkman [1983] tisztán magánvállalatos duopóliumokra vizsgált ilyen két időszakos modellt, és megállapította, hogy az első időszaki egyensúlyi kapacitások megegyeznek az azonos költségszerkezetű és kínálati viszonyú Cournot-duopólium egyensúlyi kibocsátásaival. Tanulmányunkban Kreps-Scheinkman [1983] eredményét kiterjesztjük a vegyes duopóliumok - lineáris keresleti görbe és konstans egységköltségek melletti - esetére. _____ In mixed oligopolies, private firms compete with a public firm, which at least partially aims to maximize social surplus. The authors investigate mixed duopolies in which the firms first build capacities simultaneously and then set their prices simultaneously as well. For the same two-stage game with purely private firms Kreps and Scheinkman demonstrated in 1983 that the first-stage equilibrium capacities of the two-stage game are identical with the equilibrium outputs of the Cournot duopoly. This paper extends Kreps and Scheinkman's results to mixed duopolies with linear demands and constant unit costs. It is shown that quantity pre-commitment and Bertrand competition also yield to Cournot outcomes when a public firm is involved, not only in the case of private firms.

Effect of performance feedback on perceived knowledge and likelihood to pursue continuing education

The purpose of this study was to assess the effect of performance feedback on Athletic Trainers’ (ATs) perceived knowledge (PK) and likelihood to pursue continuing education (CE). The investigation was grounded in the theories of “the definition of the situation” (Thomas & Thomas, 1928) and the “illusion of knowing,” (Glenberg, Wilkinson, & Epstein, 1982) suggesting that PK drives behavior. This investigation measured the degree to which knowledge gap predicted CE seeking behavior by providing performance feedback designed to change PK. A pre-test post-test control-group design was used to measure PK and likelihood to pursue CE before and after assessing actual knowledge. ATs (n=103) were randomly sampled and assigned to two groups, with and without performance feedback. Two independent samples t-tests were used to compare groups on the difference scores of the dependent variables. Likelihood to pursue CE was predicted by three variables using multiple linear regression: perceived knowledge, pre-test likelihood to pursue CE, and knowledge gap. There was a 68.4% significant difference (t101=2.72, p=0.01, ES=0.45) between groups in the change scores for likelihood to pursue CE because of the performance feedback (Experimental group=13.7% increase; Control group=4.3% increase). The strongest relationship among the dependent variables was between pre-test and post-test measures of likelihood to pursue CE (F2,102=56.80, p<0.01, r=0.73, R2=0.53). The pre- and post-test predictive relationship was enhanced when group was included in the model. In this model [YCEpost=0.76XCEpre-0.34 Xgroup+2.24+E], group accounted for a significant amount of unique variance in predicting CE while the pre-test likelihood to pursue CE variable was held constant (F3,102=40.28, p<0.01, r=0.74, R2=0.55). Pre-test knowledge gap, regardless of group allocation, was a linear predictor of the likelihood to pursue CE (F1,102=10.90, p=.01, r=.31, R2=.10). In this investigation, performance feedback significantly increased participants’ likelihood to pursue CE. Pre-test knowledge gap was a significant predictor of likelihood to pursue CE, regardless if performance feedback was provided. ATs may have self-assessed and engaged in internal feedback as a result of their test-taking experience. These findings indicate that feedback, both internal and external, may be necessary to trigger CE seeking behavior.

Effects of service-learning on student attitudes toward academic engagement and civic responsibility

This empirical study explored the impact of service-learning participation on high school students' attitudes toward academic engagement and civic responsibility. This study focused whether a group of high school students who participated in a service-learning project had more positive attitudes toward academic engagement and civic responsibility than their high school peers who did not participate in a service learning project. ^ Data were collected from 67 volunteer students as participants in grades 9–12. A service-learning treatment group of 34 high school students was examined relative to a comparison group of 33 high school students with similar demographic and academic characteristics. The investigator used questionnaires, an oral history/service-learning project, and interviews with the teacher-coordinators of the project to collect the data. The two surveys, one investigating high school students' attitudes about academic engagement, the other investigating high school students' attitudes toward civic responsibility, were administered in a pre-treatment/post-treatment design. There were 90 days between the pre-treatment and post-treatment administrations. A factor analysis of the civic responsibility instrument and multivariate analysis of gain scores were used to compare the means of the total aggregate scores of the treatment and comparison groups. Factor analysis was performed on the academic engagement instrument but it was determined that only the total scores could be used in subsequent analyses. Results were used to determine the efficacy of service-learning as interpreted in student attitudes toward academic engagement and student attitudes toward civic responsibility. ^ The study found no significant difference between the academic engagement and the civic responsibility attitudes of a high school service-learning project group and a high school comparison group with comparable school and similar demographic characteristics. One of the implications for educational practice and policy from the study results is a need to design and implement more powerful studies, studies implemented at many sites rather than just at two sites that were the basis of this study, and studies that investigate the research questions over longer time periods. Although it was not a focus of the study, the investigator concluded that service learning projects such as this might be more effective if they were better aligned with Dewey's principles. ^

Efficient storage and domain-specific information discovery on semistructured documents

The increasing amount of available semistructured data demands efficient mechanisms to store, process, and search an enormous corpus of data to encourage its global adoption. Current techniques to store semistructured documents either map them to relational databases, or use a combination of flat files and indexes. These two approaches result in a mismatch between the tree-structure of semistructured data and the access characteristics of the underlying storage devices. Furthermore, the inefficiency of XML parsing methods has slowed down the large-scale adoption of XML into actual system implementations. The recent development of lazy parsing techniques is a major step towards improving this situation, but lazy parsers still have significant drawbacks that undermine the massive adoption of XML. ^ Once the processing (storage and parsing) issues for semistructured data have been addressed, another key challenge to leverage semistructured data is to perform effective information discovery on such data. Previous works have addressed this problem in a generic (i.e. domain independent) way, but this process can be improved if knowledge about the specific domain is taken into consideration. ^ This dissertation had two general goals: The first goal was to devise novel techniques to efficiently store and process semistructured documents. This goal had two specific aims: We proposed a method for storing semistructured documents that maps the physical characteristics of the documents to the geometrical layout of hard drives. We developed a Double-Lazy Parser for semistructured documents which introduces lazy behavior in both the pre-parsing and progressive parsing phases of the standard Document Object Model’s parsing mechanism. ^ The second goal was to construct a user-friendly and efficient engine for performing Information Discovery over domain-specific semistructured documents. This goal also had two aims: We presented a framework that exploits the domain-specific knowledge to improve the quality of the information discovery process by incorporating domain ontologies. We also proposed meaningful evaluation metrics to compare the results of search systems over semistructured documents. ^

The effectiveness of direct -instruction and student -centered teaching methods on students' functional understanding of plagiarism

In an attempt to improve students' functional understanding of plagiarism a variety of approaches were tried within the context of a more comprehensive information literacy program. Sessions were taught as a one hour "module" inside a required communications skills class at a small private university. Approaches taken included control sessions (a straightforward PowerPoint presentation of the material), direct instruction sessions (featuring mostly direct lecture but with some seatwork as well), and student-centered sessions (utilizing role playing and group exercises). Students were taught basic content and definitions regarding plagiarism, what circumstances or instances constitute plagiarism, where to go for help in avoiding plagiarism, and what constitutes appropriate paraphrasing and citation. Pre-test and post-test scores determined students' functional understanding primarily by their ability to recognize properly and improperly paraphrased text, content understanding by their combined total score on a multiple choice quiz, and their attitude and conceptual understanding by their ability to recognize circumstances which would constitute plagiarism. While students improved across all methods the study was unable to identify one that performed significantly better than the others. The results supported the need for more education with regard to plagiarism and suggested a need for perhaps more time on task and/or a mixed approach towards conveying the content.

The effects of student -centered and traditional models of teaching on reading skills

A pre-test, post-test, quasi-experimental design was used to examine the effects of student-centered and traditional models of reading instruction on outcomes of literal comprehension and critical thinking skills. The sample for this study consisted of 101 adult students enrolled in a high-level developmental reading course at a large, urban community college in the Southeastern United States. The experimental group consisted of 48 students, and the control group consisted of 53 students. Students in the experimental group were limited in the time spent reading a course text of basic skills, with instructors using supplemental materials such as poems, news articles, and novels. Discussions, the reading-writing connection, and student choice in material selection were also part of the student-centered curriculum. Students in the control group relied heavily on a course text and vocabulary text for reading material, with great focus placed on basic skills. Activities consisted primarily of multiple-choice questioning and quizzes. The instrument used to collect pre-test data was Descriptive Tests of Language Skills in Reading Comprehension; post-test data were taken from the Florida College Basic Skills Exit Test. A MANCOVA was used as the statistical method to determine if either model of instruction led to significantly higher gains in literal comprehension skills or critical thinking skills. A paired samples t-test was also used to compare pre-test and post-test means. The results of the MANCOVA indicated no significant difference between instructional models on scores of literal comprehension and critical thinking. Neither was there any significant difference in scores between subgroups of age (under 25 and 25 and older) and language background (native English speaker and second-language learner). The results of the t-test indicated, however, that students taught under both instructional models made significant gains in on both literal comprehension and critical thinking skills from pre-test to post-test.

Impact of Vegetable Preparation Method and Taste-Test on Vegetable Preference for First Grade Children in the United States

How children rate vegetables may be influenced by the preparation method. The primary objective of this study was for first grade students to be involved in a cooking demonstration and to taste and rate vegetables raw and cooked. First grade children of two classes (N= 52: 18 boys and 34 girls (approximately half Hispanic) that had assented and had signed parental consent participated in the study. The degree of liking a particular vegetable was recorded by the students using a hedonic scale of five commonly eaten vegetables tasted first raw (pre-demonstration) and then cooked (post-demonstration). A food habit questionnaire was filled out by parents to evaluate their mealtime practices and beliefs about their child’s eating habits. Paired sample t-tests revealed significant differences in preferences for vegetables in their raw and cooked states. Several mealtime characteristics were significantly associated with children’s vegetable preferences. Parents who reported being satisfied with how often the family eats evening meals together were more likely to report that their child eats adequate vegetables for their health (p=0.026). Parents who stated that they were satisfied with their child’s eating habits were more likely to report that their child was trying new foods (p<.001). Cooking demonstrations by nutrition professionals may be an important strategy that can be used by parents and teachers to promote vegetable intake. It is important that nutrition professionals provide guidance to encourage consumption of vegetables for parents so that they can model the behavior of healthy food consumption to their children.

Efficient Storage and Domain-Specific Information Discovery on Semistructured Documents

The increasing amount of available semistructured data demands efficient mechanisms to store, process, and search an enormous corpus of data to encourage its global adoption. Current techniques to store semistructured documents either map them to relational databases, or use a combination of flat files and indexes. These two approaches result in a mismatch between the tree-structure of semistructured data and the access characteristics of the underlying storage devices. Furthermore, the inefficiency of XML parsing methods has slowed down the large-scale adoption of XML into actual system implementations. The recent development of lazy parsing techniques is a major step towards improving this situation, but lazy parsers still have significant drawbacks that undermine the massive adoption of XML. Once the processing (storage and parsing) issues for semistructured data have been addressed, another key challenge to leverage semistructured data is to perform effective information discovery on such data. Previous works have addressed this problem in a generic (i.e. domain independent) way, but this process can be improved if knowledge about the specific domain is taken into consideration. This dissertation had two general goals: The first goal was to devise novel techniques to efficiently store and process semistructured documents. This goal had two specific aims: We proposed a method for storing semistructured documents that maps the physical characteristics of the documents to the geometrical layout of hard drives. We developed a Double-Lazy Parser for semistructured documents which introduces lazy behavior in both the pre-parsing and progressive parsing phases of the standard Document Object Model's parsing mechanism. The second goal was to construct a user-friendly and efficient engine for performing Information Discovery over domain-specific semistructured documents. This goal also had two aims: We presented a framework that exploits the domain-specific knowledge to improve the quality of the information discovery process by incorporating domain ontologies. We also proposed meaningful evaluation metrics to compare the results of search systems over semistructured documents.

Circadian rhythm disruption and post-surgical recovery

Circadian rhythms, patterns of each twenty-four hour period, are found in most bodily functions. The biological cycles of between 20 and 28 hours have a profound effect on an individual's mood, level of performance, and physical well being. Loss of synchrony of these biological rhythms occurs with hospitalization, surgery and anesthesia. The purpose of this comparative, correlational study was to determine the effects of circadian rhythm disruption in post-surgical recovery. Data were collected during the pre-operative and post-operative periods in the following indices: body temperature, blood pressure, heart rate, urine cortisol level and locomotor activity. The data were analyzed by cosinor analysis for evidence of circadian rhythmicity and disruptions throughout the six day study period which encompassed two days pre-operatively, two days post-operatively, and two days after hospital discharge. The sample consisted of five men and five women who served as their own pre-surgical control. The surgical procedures were varied. Findings showed evidence of circadian disruptions in all subjects post-operatively, lending support for the hypotheses.

Inventing indigenous religious belief and practice within the spaces of Ghanaian Pentecostalism : the Mame Wata healing churches of Half Assini

Goddesses in African religions are spirits that affect humans and demand reverence from them. They are also embodiments of ideas that African people have about women, their powers and their roles in society. This study focused on Mame Wata, a goddess in Half Assini, an Nzema-speaking coastal community in western Ghana. It sought to resolve a paradox, that is, the fact that, the goddess is at the center of a Pentecostalist tradition even though traditional Pentecostalism in Ghana views her as an agent of the devil. The study involved fieldwork in this community of the goddess's female worshippers led by Agyimah, a charismatic man, and an agent of the goddess. The study interpreted the goddess as a post-colonial invented symbol personifying both pre-colonial and emerging ideas about female power. Findings from the study also show that through Mame Wata the followers celebrate the spirituality of the female.

The first time delivery of the first link learning series using Skype and YouTube

Introduction: This case study documented the experiences of informal and service providers who participated in the first time delivery of the First Link Learning Series from May–August 2013 in Newfoundland and Labrador. The aim of this study was to understand how informal caregivers of people with dementia experience this Internet mediated health resource, and how Skype and YouTube can be used as tools for the Alzheimer Society of Newfoundland and Labrador to effectively deliver the First Link Learning Series. Methods: Sources of data included key informant interviews (n=3), pre- study and post-study interviews with informal dementia caregivers (n=2), institutional documentation, field notes, and YouTube analytics. Framework Analysis was used to make meaning of the qualitative data, and descriptive statistics were used to report on quantitative outcomes. Findings: Between 3% and 17% of registered First Link clients attended the learning series sessions, however only two caregivers participated using Skype or YouTube. Framework Analysis revealed three shared themes: access, connection and privacy. Discussion: The themes helped to begin building theory about barriers and facilitators to Internet mediated health resources for informal dementia caregivers. Experiences of service providers using the Internet to support clients served to begin building a case for the appropriateness of these media. A modified version of Dansky et al.’s (2006) theoretical framework for evaluating E-Health research that situates the person/user in the model, helped guide discussion and propose future directions for the study of Internet based health resources for informal dementia caregivers.

Weighted nucleoli and dually essential coalitions

We consider linearly weighted versions of the least core and the (pre)nucleolus and investigate the reduction possibilities in their computation. We slightly extend some well-known related results and establish their counterparts by using the dual game. Our main results imply, for example, that if the core of the game is not empty, all dually inessential coalitions (which can be weakly minorized by a partition in the dual game) can be ignored when we compute the per-capita least core and the per-capita (pre)nucleolus from the dual game. This could lead to the design of polynomial time algorithms for the per-capita (and other monotone nondecreasingly weighted versions of the) least core and the (pre)nucleolus in specific classes of balanced games with polynomial many dually esential coalitions.

Clinical characteristics and benefit of cataract intervention amongst UK domiciliary eye care recipients

Purpose: Given the ageing UK population and the high prevalence of activity-limiting illness and disability in the over 65s, the demand for domiciliary eye care services is set to grow significantly. Over 400,000 NHS domiciliary eye examinations are conducted each year, yet minimal research attention has been directed to this mode of practice or patient needs amongst this group. The study aimed to compare clinical characteristics and benefits of cataract surgery between conventional in-practice patients and domiciliary service users. Methods: Clinical characteristics were compared between patients in North-West England receiving NHS domiciliary eye care services (n = 197; median age 76.5 years), and an age-matched group of conventional in-practice patients (n = 107; median age 74.6 years). Data including reason for visit; logMAR uncorrected and best corrected distance (UDVA and CDVA) and near acuities (UNVA and CNVA); presence of ocular pathology and examination outcome were documented retrospectively. To compare the benefit of cataract surgery in terms of functional capacity between the patient groups, individuals undergoing routine referral for first-eye surgery completed the VF-14 questionnaire pre-operatively, and at 6 weeks post-operatively. Results: UDVA was similar between the two groups (median 0.48 and 0.50 logMAR in the domiciliary and practice groups, P = 0.916); CDVA was significantly worse in the domiciliary group (median 0.18 vs 0.08 logMAR, P<0.001), who were more likely to have clinically-significant cataract. Both groups showed similar improvements in VF-14 scores following cataract surgery (mean gains 24.4 ± 11.7, and 31.5 ± 14.7 points in the in-practice and domiciliary groups, respectively. P = 0.312). Conclusions: Patients receiving domiciliary eye care services are more likely to have poorer corrected vision than in-practice patients of a similar age, partly due to a higher prevalence of significant cataract. Despite limitations in their activities due to illness and disability, domiciliary patients experience similar gains in self-reported functional capacity following cataract surgery

The effect of gestational and lactational age on the human milk metabolome

Human milk is the ideal nutrition source for healthy infants during the first six months of life and a detailed characterisation of the composition of milk from mothers that deliver prematurely (<37 weeks gestation), and of how human milk changes during lactation, would benefit our understanding of the nutritional requirements of premature infants. Individual milk samples from mothers delivering prematurely and at term were collected. The human milk metabolome, established by (NMR) spectroscopy, was influenced by gestational and lactation age. Metabolite profiling identified that levels of valine, leucine, betaine, and creatinine were increased in colostrum from term mothers compared with mature milk, while those of glutamate, caprylate, and caprate were increased in mature term milk compared with colostrum. Levels of oligosaccharides, citrate, and creatinine were increased in pre-term colostrum, while those of caprylate, caprate, valine, leucine, glutamate, and pantothenate increased with time postpartum. There were differences between pre-term and full-term milk in the levels of carnitine, caprylate, caprate, pantothenate, urea, lactose, oligosaccharides, citrate, phosphocholine, choline, and formate. These findings suggest that the metabolome of pre-term milk changes within 5-7 weeks postpartum to resemble that of term milk, independent of time of gestation at pre-mature delivery.

Effect of Performance Feedback on Perceived Knowledge and Likelihood to Pursue Continuing Education

The purpose of this study was to assess the effect of performance feedback on Athletic Trainers’ (ATs) perceived knowledge (PK) and likelihood to pursue continuing education (CE). The investigation was grounded in the theories of “the definition of the situation” (Thomas & Thomas, 1928) and the “illusion of knowing,” (Glenberg, Wilkinson, & Epstein, 1982) suggesting that PK drives behavior. This investigation measured the degree to which knowledge gap predicted CE seeking behavior by providing performance feedback designed to change PK. A pre-test post-test control-group design was used to measure PK and likelihood to pursue CE before and after assessing actual knowledge. ATs (n=103) were randomly sampled and assigned to two groups, with and without performance feedback. Two independent samples t-tests were used to compare groups on the difference scores of the dependent variables. Likelihood to pursue CE was predicted by three variables using multiple linear regression: perceived knowledge, pre-test likelihood to pursue CE, and knowledge gap. There was a 68.4% significant difference (t101= 2.72, p=0.01, ES=0.45) between groups in the change scores for likelihood to pursue CE because of the performance feedback (Experimental group=13.7% increase; Control group= 4.3% increase). The strongest relationship among the dependent variables was between pre-test and post-test measures of likelihood to pursue CE (F2,102=56.80, p<0.01, r=0.73, R2=0.53). The pre- and post-test predictive relationship was enhanced when group was included in the model. In this model [YCEpost=0.76XCEpre-0.34 Xgroup+2.24+E], group accounted for a significant amount of unique variance in predicting CE while the pre-test likelihood to pursue CE variable was held constant (F3,102=40.28, p<0.01,: r=0.74, R2=0.55). Pre-test knowledge gap, regardless of group allocation, was a linear predictor of the likelihood to pursue CE (F1,102=10.90, p=.01, r=.31, R2=.10). In this investigation, performance feedback significantly increased participants’ likelihood to pursue CE. Pre-test knowledge gap was a significant predictor of likelihood to pursue CE, regardless if performance feedback was provided. ATs may have self-assessed and engaged in internal feedback as a result of their test-taking experience. These findings indicate that feedback, both internal and external, may be necessary to trigger CE seeking behavior.