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Purpose: This study investigates internal/own shock in the domestic market and three external volatility spillovers from India, the UK, and the USA to the Sri Lanka stock market.

Need for the Study: The external market’s internal/own shocks and volatility spillovers influence portfolio choices in domestic stock market returns. Hence, it is required to investigate the internal shock in the domestic market and the external volatility spillovers from other countries.

Methodology: This study employs a quantitative method using ARMA(1,1)-GARCH(1,1) model. All Share Price Index (ASPI) is the proxy for the Colombo Stock Exchange (CSE) stock return. It uses daily time-series data from 1^st April 2010 to 21^st June 2023.

Findings: The findings revealed that internal/own and external shocks substantially impact the stock price volatility in CSE. Significant volatility clusters and persistence with extended memory in ASPI confirm internal/own shock in the market. Furthermore, CSE receives significant volatility shock from the USA, confirming external shock. This study’s findings highlight the importance of considering internal and external shocks in portfolio decision-making.

Practical Implications: Understanding the influence of internal shocks helps investors manage their portfolios and adapt to market volatility. Recognising significant volatility spillovers from external markets, especially the USA, informs diversification strategies. From a policy standpoint, the study emphasises the need for robust regulations and risk management measures to address shocks in domestic and global markets. This study adds value to the literature by assessing the sources of volatility shocks in the CSE, employing the ARMA-GARCH, a sophisticated econometrics model, to capture stock returns volatility, enhancing understanding of the CSE’s volatility dynamics.

Classical unit root tests are known to suffer from potentially crippling size distortions, and a range of procedures have been proposed to attenuate this problem, including the use of bootstrap procedures. It is also known that the estimating equation’s functional form can affect the outcome of the test, and various model selection procedures have been proposed to overcome this limitation. In this chapter, the authors adopt a model averaging procedure to deal with model uncertainty at the testing stage. In addition, the authors leverage an automatic model-free dependent bootstrap procedure where the null is imposed by simple differencing (the block length is automatically determined using recent developments for bootstrapping dependent processes). Monte Carlo simulations indicate that this approach exhibits the lowest size distortions among its peers in settings that confound existing approaches, while it has superior power relative to those peers whose size distortions do not preclude their general use. The proposed approach is fully automatic, and there are no nuisance parameters that have to be set by the user, which ought to appeal to practitioners.

This chapter revisits the Hausman (1978) test for panel data. It emphasizes that it is a general specification test and that rejection of the null signals misspecification and is not an endorsement of the fixed effects estimator as is done in practice. Non-rejection of the null provides support for the random effects estimator which is efficient under the null. The chapter offers practical tips on what to do in case the null is rejected including checking for endogeneity of the regressors, misspecified dynamics, and applying a nonparametric Hausman test, see Amini, Delgado, Henderson, and Parmeter (2012, chapter 16). Alternatively, for the fixed effects die hard, the chapter suggests testing the fixed effects restrictions before adopting this estimator. The chapter also recommends a pretest estimator that is based on an additional Hausman test based on the difference between the Hausman and Taylor estimator and the fixed effects estimator.

The increasing accumulation of synthetic plastic waste in oceans and landfills, along with the depletion of non-renewable fossil-based resources, has sparked environmental concerns and prompted the search for environmentally friendly alternatives. Biodegradable plastics derived from lignocellulosic materials are emerging as substitutes for synthetic plastics, offering significant potential to reduce landfill stress and minimise environmental impacts. This study highlights a sustainable and cost-effective solution by utilising agricultural residues and invasive plant materials as carbon substrates for the production of biopolymers, particularly polyhydroxybutyrate (PHB), through microbiological processes. Locally sourced residual materials were preferred to reduce transportation costs and ensure accessibility. The selection of suitable residue streams was based on various criteria, including strength properties, cellulose content, low ash and lignin content, affordability, non-toxicity, biocompatibility, shelf-life, mechanical and physical properties, short maturation period, antibacterial properties and compatibility with global food security. Life cycle assessments confirm that PHB dramatically lowers CO₂ emissions compared to traditional plastics, while the growing use of lignocellulosic biomass in biopolymeric applications offers renewable and readily available resources. Governments worldwide are increasingly inclined to develop comprehensive bioeconomy policies and specialised bioplastics initiatives, driven by customer acceptability and the rising demand for environmentally friendly solutions. The implications of climate change, price volatility in fossil materials, and the imperative to reduce dependence on fossil resources further contribute to the desirability of biopolymers. The study involves fermentation, turbidity measurements, extraction and purification of PHB, and the manufacturing and testing of composite biopolymers using various physical, mechanical and chemical tests.

This research is located at the intersection of communication, memetics, and the study of the imaginary. As a presupposition, we put forward the existence of a communicational imaginary, in which the contemporary person functions through their competencies in social networks, by meeting the demands of the public and the private, managing the obsessiveness of the sharing of intimacy and the exorbitant number of images. Considering memes as a significant aspect of this communicational imaginary, we seek to understand the dynamics and path of memes in the midst of this plethora of images. From the concept of iconophagy, we deal with the exacerbated multiplication of the images and the path of memes starting from a marginalized environment until it is integrated into social roles and a rational level of thought. Thus, it is the general objective of this research to understand the dynamics and the path of memes amidst the plethora of images in the context of communicational imagery and to investigate the multiplication of memes as representative of the myriad images in contemporary imagery.

This chapter details a practice-based investigation of a 19th-century astronomical device known as ‘Janssen’s apparatus’. It questions traditional narratives of linear technological advancement and ‘sole inventor’ to reframe the historical artefact as a site which makes visible a network of technological knowledge interconnecting astronomy and visual culture. Approached from this perspective, the Janssen artefact is reframed as an ‘intersite of knowledge’, exploring how the various know-how contained within the device is located across disciplines rather than within a single field. Originally developed to calculate the Astronomical Unit during the 1874 Transit of Venus, Janssen’s apparatus failed in its endeavour as a measuring instrument, but its motion mechanism was successfully adapted into early cinema technologies. This chapter applies praxis through the development of a prototype artwork and the concept of ‘techne’ as speculative means of understanding how this mechanism was transferred from astronomy to the Western cultural realm. It proposes that the development of the apparatus was partially gleaned from moving image techniques already in use within 19th-century visual culture. The development of the prototype artwork is discussed in relation to the specific timing mechanism of the Janssen apparatus and how it establishes its own ‘intersite of knowledge’ relevant to its contemporary context. Finally, this chapter elaborates on how witnessing the Janssen mechanism in motion provided unique insight and how creating a dialogue between historical and contemporary apparatus facilitates a reconsideration of how galleries, libraries, archives, and museums [GLAM] and other host institutions that contain artefacts might share their hidden stories.