New Variance Ratio Tests to Identify Random Walk from the General Mean Reversion Model

We develop some properties on the autocorrelation of the k-period returns for the general mean reversion (GMR) process in which the stationary component is not restricted to the AR(l) process but take the form of a general ARMA process. We then derive some properties of the GMR process and three new non-parametric tests comparing the relative variability of returns over different horizons to validate the GMR process as an alternative to random walk. We further examine the asymptotic properties of these tests which can then be applied to identify random walk models from the GMR processes.mean reversion, variance ratio test, random walk, stock price, stock return

Culture technoscientifique, corporéisation et wuta pians

À partir de l’analyse des films de Kungfu produits à Hong Kong, cet article met en évidence les rapports qu’entretient cet art martial, considéré ici comme un discours en soi, avec la technologie et la science. Plusieurs des composantes du Kungfu, qui peuvent être mises en parallèle avec celles de la technologie moderne. On étudiera, à titre d’exemples, la séquence pause-explosion-pause relevée par David Bordwell, la force expressive des sauts et des coups de poing, l’expressivité de l’impression cinétique, les différents affects qui naissent des ruptures rythmiques, la subtile symbiose qui s’établit entre l’arme et le lutteur, entre autres manifestations. Ces différents éléments, ainsi que ses emprunts aux préceptes médicaux et scientifiques du Qi Kung, permettent de dégager de l’analyse du discours kung-fu, la notion de corporéisation technologique.This paper is focused on Kungfu itself as a discourse which is closely related to technology and science. Kungfu movies made in Hong Kong are used to demonstrate how the technological aspects can be juxtaposed with the built-in technology of Kungfu, such as David Bordwelf's ideas of pause-burst-pause pattern, the expressive force of jumping, punching, the kinetic impact and expressivity, the kind of affects generated from rhythmic differentiality, the nuanced interconnectedness between fighters and their weapons, the kind of difference in intensity and rhythms based on the medical and scientific concepts of Qi Kung, etc. How Kungfu discourse can be used as exemplary of the concept of "Embodying technesis" will be explored

Work-Family Conflict and Facilitation among Employees in Hong Kong

Work-family imbalance can induce negative consequences, such as poor physical and psychological well-being for individuals. Hong Kong employees commonly agree that work-family balance is important for them, but it is difficult to balance work and family lives (Mahtani, 2006). Very few studies have comprehensively explored how to eliminate the conflict, and to enhance the integration between work and family domains. This may hinder researchers and practitioners from exploring effective strategies for promoting work-family balance. The present study explored work-family conflict and enrichment among Hong Kong employees. This study examined the relationships between demands and resources in work and family lives, work-family conflict and enrichment, personal and work outcomes, and optimism and Confucian work values as moderator variables. The longitudinal mediating effects of work-family conflict and enrichment were examined, and potential cross-sectional and longitudinal moderating effects on the relationships between predictor variables and work-family conflict and enrichment were also explored. A two-wave panel design was adopted with data collection separated by a ten-month interval. Questionnaires were designed for the participants and their supervisors. 509 participants at Time 1 and 208 participants at Time 2 from three universities in Hong Kong completed self-report questionnaires, and 208 supervisors of the participants completed another questionnaire at Time 2. Predictor variables at work were significantly associated with work-family conflict and enrichment perceived in the work domain, and predictor variables in the family domain were significantly related to work-family conflict and enrichment perceived in the family domain. Work-family conflict and enrichment were significantly associated with personal and work outcomes. Mediation analyses showed that there were very few longitudinal mediating effects of work-family conflict and enrichment between predictor and criterion variables. These findings suggest that work-family conflict and enrichment might not consistently contribute mediating effects in the relationships between these predictor and criterion variables over time. Potential effects of optimism and Confucian work values have been rarely explored in previous Chinese work-family studies, and therefore this study examined the moderating effects of these two variables in relation to work-family conflict and enrichment. However, moderating analyses indicated that there were very few cross-sectional and longitudinal moderating effects of optimism and Confucian work values confirmed in this study. Overall, the findings of this research illustrate that work-family conflict and enrichment could be separately affected by demands and resources in work and family lives. Work-family conflict and enrichment could also contribute significant effects on individuals’ well-being and work productivity. The results also imply that the significance of mediation and moderation effects for work-family conflict and enrichment might be determined by personal factors (e.g. coping strategies of individuals) or organisational factors (e.g. organisational culture). The present study separately examined two directions of work-family conflict and enrichment, which extends the understanding of these topics in the Chinese context. The findings support related Western literature that perceived work-family conflict and enrichment in one domain were determined by the source in the same domain, and each direction of conflict or enrichment was associated with outcomes in the domain receiving the conflict or enrichment. These findings may extend the discussion of the relationships between potential factors and consequences of work-family conflict and enrichment for Hong Kong employees. The present study also provided additional information to understand the relationships between cultural values and work-family conflict and enrichment. The results may aid practitioners to formulate appropriate interventions, such as family-friendly employment policies and practices in enhancing work-family balance in Hong Kong

A study of learning styles of engineering students in vocational education in Hong Kong

Students have different learning preferences of receiving, processing and internalizing knowledge and skills. If the learning environment is advantageous to the learning styles of the students, there is a higher chance that the students can achieve the intended learning outcomes. Previous research on understanding the learning styles of students suggests that the use of learning style models helped teachers design effective instruction and could help students better understand their own learning preferences. Felder and Silverman (1988) proposed a learning style model, which was designed to capture the important learning style differences among engineering students. The model categorised learning preferences into four dimensions, namely, active/reflective, sensing/intuitive, visual/verbal, and sequential/global (Felder and Spurlin, 2005). After identifying the learning styles of the students, corresponding teaching strategies can then be developed for more effective learning. This research was an preliminary investigation of learning styles of engineering students studying vocationally oriented higher diploma programmes in Hong Kong. Data from over 140 students in two engineering programmes was collected and analysed to identify the learning characteristics of students. It was found that the sample students were marginally reflective, predominately sensing, visual, and sequential learners. Observations from the analysed data provided valuable information for teachers to design more effective teaching strategies

The theory of generalized purchasing power parity: multivariate cointegration and dynamic analysis of cointegrating systems

Unit root tests, augmented Dickey-Fuller and Phillips-Perron tests, indicate that the bilateral real exchange rates of six small Asian countries (India, Indonesia, Korea, the Philippines, Singapore, and Thailand) and three larger countries (Germany, the U.K., and the U.S.) are not stationary, and each has a unit root over the period January 1973 to December 1989 (i.e., a period of flexible exchange rates). This result does not support purchasing power parity (PPP);The theory of Generalized Purchasing Power Parity (Generalized-PPP) is developed due to the failure of PPP. Generalized-PPP states that the bilateral real exchange rates are, in general, non-stationary since the real fundamental variables are generally non-stationary. If the real fundamental variables of some countries share common trends, these countries\u27 real exchange rates will share the same common trends. By sharing the common trends, these countries\u27 real exchange rates are cointegrated, and there exists at least one stationary linear combination of the real exchange rates. Indeed, PPP is just a special case of Generalized-PPP;Tests for the performance of Generalized-PPP by Johansen\u27s multivariate cointegration methodology are presented. There is evidence in support of Generalized-PPP for the Asian countries as long as the Singapore real exchange rate is included. It is likely that the Singapore real exchange rate is the main linkage for the existence of Generalized-PPP in Asia. On the other hand, Generalized-PPP does hold for each of the small Asian countries (except India) with the three large countries (Germany, the U.K., and the U.S.);The existence of Generalized-PPP implies that there is an error correction model. Using this model, it is possible to use the resulting impulse response functions to trace out the time paths of the various small Asian countries\u27 real exchange rates for shocks in the real exchange rates of larger countries. Both the results of variance decomposition and the impulse response functions indicate that the real exchange rate movements in the small Asian countries are influenced by the shocks in large countries\u27 real exchange rates, especially the largest country, the U.S

The treeing-of-tree through affective attunement: biosemiotics and chinese ideograms as an ecosystem

Este trabalho se insere na esteira dos desenvolvimentos recentes de uma “virada ecológica” nas teorias da naturacultura ociental, tendo em vista o paradigma crítico chamado “biossemiótica”. Ele se propõe aventurar-se pela crítica literária interseccionalmente transversal, a ontologia quiasmática, a teoria afetiva, a bioneneurologia, a pesquisa científica e filosófica sobre os estudos faunísticos e florísticos, de modo a descobrir um caminho para uma ecocrítica/ecolinguística chinesa sob a égide das humanidades ambientais. O ensaio parte de um grupo entrelaçado de ideogramas chineses que se apresentam com radicais associados com plantas (mu 木 como elemento “planta/madeira”), e que exibe um amplo espectro de interações planta-ambiente visando a uma empatia afetiva com o agenciamento da vida vegetal. Ele cria, assim, um clima para repensarmos o tema estudo crítico de plantas, estabelecendo uma forma biocêntrica ou fitocêntrica de crítica. Com uma ênfase em mu como um dos elementos da cosmologia wu-xing 五行 da cultura clássica chinesa, esperamos que o esforço amplie o âmbito e a dimensão da biossemiótica como sugerida por Derrida, Merleau-Ponty, Spinoza, Deleuze, Uexküll, Hoffmeyer e Wheeler, mediante uma abordagem entrecruzada não apenas em áreas críticas, mas também entre as culturas do ocidente e do orientee em geral

Removal of CO? from Natural Gas by Polyimide Membrane In the Presence of Heavy Hydrocarbon

Carbon dioxide, heavy hydrocarbon, hydrogen sulfide, water vapor and toluene are the common impurities found in raw natural gas that can bring detrimental effects on the performanceof membrane. The heavy hydrocarbon contamination can cause the loss of flux and membrane performance and thus it is imperative for pretreatment of the natural gas feed stream to remove the contaminants. This project is to study the effect of heavy hydrocarbon on the polyimide membrane performance in separating gas CO2 from natural gas feed stream at designed operating parameters, i.e. feed pressure, temperature and C02 concentration in feed. Liquid Pentane (C5H12) is used as a basis to simulate the presence of heavy hydrocarbon in the experiments. Gas permeation experiments have been conducted in laboratory to study the effect of pentane on Polyimide membrane performance. It is proven that permeance of C02 and CH4will decrease with an increase in operating pressure at feed side in both dry and wet condition. The CO2/CH4 selectivity increases with an increase in feed pressure. Higher operating temperatures increased C02 and CH4 permeance but decreased CO2/CH4 selectivity of polyimide membrane. An increase in CO2 concentrationin feed compositionincreases the losses of hydrocarbon but reduced C02, CH4 permeance and C02/CH4 selectivity. The decrease of membrane permeance and selectivity with an increase in C02 concentration in the feed compositionis due to the plasticization and coupling effect. The pentane presence in the feed gas caused swelling or plasticization of polyimide membrane and lead to the reduction in membrane selectivity. It was concluded that the presence of pentane as heavy hydrocarbon in natural gas stream contributed to the loss of membraneselectivity and caused the separationperformance of the membranesystem become less efficient