SRI LANKAN STOCK MARKET VOLATILITY ANALYSIS: AN ARMA- GARCH APPROACH

Beyond its role in capital generation, a stock market is emulated as a facet in economic development indication. Sri Lankan stock market, the Colombo Stock Exchange (CSE) is a languidly developing market known for instability and periodical fluctuations increasing the volatility risk for the investors. Toward market development, it is imperative in attracting and retaining long term investors. Thus, the study aimed to identify the dynamics of the CSE through volatility estimation of the Sri Lankan stock market during a high volatile period. Further, the use of ARMA-GARCH models aims to contribute to the local empirical studies on the applicability of ARMA-GARCH models in the Sri Lankan context. The study used the daily closing prices of the All-Share-Price Index (ASPI) from January 2018 to December 2022 in log return volatility. Owing to the non-normality and serial dependence conditions inherent in the data, the study developed an ARMA (2,2) mean equation and separate volatility equation applying symmetric models of GARCH, and TGARCH and asymmetric GARCH models of EGARCH, and GJR-GARCH. The study findings identified that asymmetric GARCH models are more reliable in volatility estimation and forecasting. Further, ASPI indicated a leverage effect where negative information caused idiosyncratic volatility. Keywords: ARMA-GARCH, GARCH, Leverage Effect, Stock Markets, Volatility &nbsp

Have out-of-pocket health care payments risen under free health care policy?

Compared to its neighbors, Sri Lanka performs well in terms of health. Health care is provided for free in the public sector, yet households' out-of-pocket health expenditures are steadily increasing. We explore whether this increase can be explained by supply shortages and insufficient public health care financing or whether it is rather the result of an income-induced demand for supplementary and higher quality services from the private sector. We focus on total health care expenditures and health care expenditures for specific services such as expenses on private outpatient treatments and expenses on laboratory and other diagnostic services. Overall, we find little indication that limited supply of public health care per se pushes patients into the private sector. Yet income is identified as one key driver of rising health care expenditures, ie, as households get richer, they spend an increasing amount on private services suggesting a dissatisfaction with the quality offered by the public sector. Hence, quality improvements in the public sector seem to be necessary to ensure sustainability of the public health care sector. If the rich and the middle class increasingly opt out of public health care, the willingness to pay taxes to finance the free health care policy will certainly shrink

Pediatric provider perspectives and practices regarding health policy discussions with families: a mixed methods study

Background Advocacy regarding child health policy is a core tenet of pediatrics. Previous research has demonstrated that most pediatric providers believe collective advocacy and political involvement are essential aspects of their profession, but less is known about how pediatric providers engage with families about policy issues that impact child health. The objectives of this study were to examine providers’ perceptions and practices with regards to discussing health policy issues with families and to identify provider characteristics associated with having these discussions. Methods In this cross-sectional mixed methods study, pediatric resident physicians, attending physcians, and nurse practitioners at primary care clinics within a large academic health system were surveyed to assess (1) perceived importance of, (2) frequency of, and (3) barriers to and facilitators of health policy discussions with families. Multivariable ordinal regression was used to determine provider characteristics (including demographics, practice location, and extent of civic engagement) associated with frequency of these discussions. A subset of providers participated in subsequent focus groups designed to help interpret quantitative findings. Results The overall survey response rate was 155/394 (39%). The majority of respondents (76%) felt pediatricians should talk to families about health policy issues affecting children, but most providers (69%) reported never or rarely having these discussions. Factors associated with discussing policy issues included being an attending physician/nurse practitioner (OR 8.22, 95% CI 2.04–33.1) and urban practice setting (OR 3.85, 95% CI 1.03–14.3). Barriers included feeling uninformed about relevant issues and time constraints. In provider focus groups, four key themes emerged: (1) providers felt discussing policy issues would help inform and empower families; (2) providers frequently discussed social service programs, but rarely discussed policies governing these programs; (3) time constraints and concerns about partisan bias were a barrier to conversations; and (4) use of support staff and handouts with information about policy changes could help facilitate more frequent conversations. Conclusions Pediatric providers felt it was important to talk to families about child health policy issues, but few providers reported having such conversations in practice. Primary care practices should consider incorporating workflow changes that promote family engagement in relevant health policy discussions

Sensor fusion model for low cost mobile robot platform

This project investigates the general robots behavior, control and Multi-Sensor sensory fusion techniques using low cost Infra-red (1R) sensors, Sonar sensors (Ultrasonic sensors), Optical encoders and general-purpose Web camera specially CMUcam CMOS camera. According to my literature survey 1 have found that current high - tech researches are going on by applying very expensive and sophisticated sensory devices such as, Stereo-Vision sensors, Laser scanners, High resolution CCD camera etc. along with embedded high speed Digital Signal Processor (DSP) systems. Due to above technical and financial restrictions facing with research as well as depth of expected research study to be performed; very complex and highly expensive components should have been eliminated and would not be illustrated further. This project particularly based on sensory fusion with image processing techniques. The objective as well as motivation is, to build a low cost, optimal level resource consuming reliable sensory system for a robot. Relying only one sensor especially the time - of flight sensor (sonar) will probably cause problems such as, sonar sensors are limited in resolution, range and the size of the object they can detect, sensor value (from sonar) may not correspond to the actual distance of the object, cross talk, fore shorting and specula reflection. Sensors sometimes can be complementary or redundant since it is necessary to make an appropriate selection of sensors when building the sensor suit for a mobile robot. For an example, Infra-Red (IR) can provide less-accurate range measurements compared to the ultrasonic sensors but IR sensors can provide a large number of measurements in a short time period; can easily be mounted on a scanner to provide panoramic view and sonar sensors are excellent for mobile robot applications when especially navigate through a room filled with obstacles. In many cases multiple sensor sources are better than single sensor reading. This led to the development of the sensor system architecture with sensory fusion techniques. Further, this permits more than one sensor making the sensory system more reliable and robust. Typically the general architecture of the fusion sensor has been categorized into two; low-level fusion and high-level fusion. In this project, the architecture is developed based on actionoriented sensory fusion, in belief that multiple sensor reading can be fused and would give rise to certain behavior for mobile robot. And also Filtering techniques are employed to reduce the uncertainties in the line segment representation and Data / Image fusion. Some of the issues in designing particular vision system for the robot, involves capturing and storing the entire image before starting the image analysis and to overcome some of general vision system issues, system has to be designed to extract visual information from the environment in Real-Time using an affordable 'off - the - shell' digital CMU cam color camera and embedded controller. The final implementation and results were obtained by using Simrobot simulations and real low cost mobile platform was developed to certify the trialed simulations and implemented behaviors. It is discussed that complex situations such as emergency behavioral decision making, significantly deviates from expected once so that vision and image processing in real time make hardcore experience in low cost camera 1 had used and also uncertainty of sensor inputs truly make unexpected fusion results with noise addition as well

DEMAND FOR PRIVATE TUITION CLASSES UNDER THE FREE EDUCATION POLICY. EVIDENCE FROM SRI LANKA

Private tuition is a growing phenomenon in Sri Lanka especially among students who prepare for competitive national school qualifying examinations. Private tuition classes are one of major education issues under the free education policy in Sri Lanka as it can damage the purpose of free education policy. This study examined the determinants of household private tuition expenditure in Sri Lanka. The study is based on two Household Income and Expenditure Surveys (HIES) of Sri Lanka conducted by the Department of Census and Statistics (DCS) in 1995/96 and 2006/07. Using descriptive statistics and Tobit model estimation framework, we find that household demand for private tuition classes has increased in recent time. Household private tuition expenditure was a luxury good of consumer’s budget in 1995/96 but it has gradually become necessity good in 2006/07. Moreover,parental education level is found to be an important factor of household private tuition expenditure. Increasing demand for private tuition classes is a growing concern because Sri Lankan government provides free school education up to university level. Education policy makers may have to take steps to improve school quality as household demand for additional private tuition classes was found to have increased with competitive schoolqualifying exams in recent time.Key Words: Private Tuition Classes, Household Expenditure, Free Education Policies, Tobit Estimator

Recent Developments in Noble Metal-Free Catalysts for a Photocatalytic Water Splitting Process—A Review

Sustainable hydrogen production is an essential prerequisite of a future hydrogen economy. Compared to other processes such as renewable energy-driven water electrolysis and photoelectrochemical water splitting, direct solar to hydrogen conversion through photocatalytic water splitting gives the simplest system for sustainable hydrogen production. Among the many factors to be considered such as the availability of solar radiation, gas collection mechanism and other infrastructure, a highly active noble metal-free photocatalyst is essential to make the water splitting process more energy efficient and economical. This review highlights the mechanism and factors hindering the efficiency of catalysts in photocatalytic water splitting, while discussing recent research efforts towards the development of highly efficient, noble metal-free photocatalysts, especially at the nanoscale, and their catalytic properties for water splitting. Mainly, catalysts consisting of TiO2, Z-schemed catalytic systems and naval computational approaches are discussed here. Moreover, techniques to enhance their catalytic activities and the developments required for the implementation of these photocatalytic systems at a commercial scale are further emphasized in the discussion section

Dual layered multi agent system for intentional islanding operation of microgrids

The paper focuses on proposing a dual layered, multi agent based control system for distributed control of a microgrid aimed at intentional islanding. The architecture consists of two layers; primary layer and secondary layer. The primary layer includes a User agent, a Distributed Generator (DG) agent and a Control agent. The secondary layer consists of a Low Voltage (LV) agent and a Load agent. The Control agent is capable of supervising the secondary layer agents. The proposed multi agent based control architecture is developed using the JADE platform and it is used to control a microgrid simulated in MATLAB/SIMULINK. In order to validate the effectiveness of the proposed method, investigations are carried out for islanding scenarios simulated on the test network. The results of this study show the capability of developing a reliable control mechanism for islanding operation of microgrids based on the proposed concept

Intelligent behaviors and sensor fusion for mobile robot based on fuzzy realization

This paper describes how fuzzy control can be applied to a sonar-based mobile robot. Behavior-based fuzzy control for robot behaviors was designed using sonar sensors. (10) Throughout this research work experimental mobile robot is used as the development platform to embody some basic behaviors. That can further be combined to build more complex behaviors. Avoid - Obstacle, Left-Right wall following, Move To-Point, Vision information detection and Emergency behaviors will be designed and embody as basic robot behaviors. (1) However, this effort basically emphasized in terms of sonar base obstacle avoidance behavior. The results show that Fuzzy behaviors are used to make the robot work intelligently, where Fuzzy rules are defined based on the tasks. The final robot commands will be depended on the Fuzzy selection that integrates and coordinates all behaviors, in which a simple Fuzzy reasoning is assigned to one elemental behavior consisting of a single input - output relation. The most of the behaviors are encoded using Fuzzy Sets and the coordination of the behaviors is done through subsumption Architecture. The Mobotsim and Matlab based mobile robot simulators were used to simulate the robot’s behaviors individually in real world situations. The robot can avoid all obstacles that are detected by sonar sensors. The task behaviors show that robot forward as the user assigns and moves to follow the wall by using the wall following behavior. The distance between the robot and wall can be controlled by using the fuzzy controller. However, in some situations the robot may stop if the objects are moved very quickly close to the robot. The simulated results demonstrate that each behavior works near accurately. The robot can avoid obstacles detected by the sonar sensors