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We examine the role of structural breaks in forecasting stock return volatility. We begin by testing for structural breaks in the unconditional variance of daily returns for the S&P 500 market index and ten sectoral stock indices for 9/12/1989–1/19/2006 using an iterative cumulative sum of squares procedure. We find evidence of multiple variance breaks in almost all of the return series, indicating that structural breaks are an empirically relevant feature of return volatility. We then undertake an out-of-sample forecasting exercise to analyze how instabilities in unconditional variance affect the forecasting performance of asymmetric volatility models, focusing on procedures that employ a variety of estimation window sizes designed to accommodate potential structural breaks. The exercise demonstrates that structural breaks present important challenges to forecasting stock return volatility. We find that averaging across volatility forecasts generated by individual forecasting models estimated using different window sizes performs well in many cases and appears to offer a useful approach to forecasting stock return volatility in the presence of structural breaks.

This article reviews the extensive history of dynamic performance research, with the goal of providing a clear picture of where the field has been, where it is now, and where it needs to go. Past research has established that job performance does indeed change, but the implications of this dynamism and the predictability of performance trends remain unresolved. Theories are available to help explain dynamic performance, and although far from providing an unambiguous understanding of the phenomenon, they offer direction for future theoretical development. Dynamic performance research does suffer from a number of methodological difficulties, but new techniques have emerged that present even more opportunities to advance knowledge in this area. From this review, I propose research questions to bridge the theoretical and methodological gaps of this area. Answering these questions can advance both research involving job performance prediction and our understanding of the effects of human resource interventions.

The chapter is a practise led example of how the inclusive pedagogical approach in action (IPAA) framework lives as evidence of inclusive pedagogy. In particular it draws on understandings of cross-curriculum design as an approach that supports teaching practises for all children. Some readers may be familiar with the language of curriculum differentiation. Commonalties may be seen in the approaches that advocate for curriculum differentiation and cross-curriculum design, however not a lot is gained by adding another language game or rule of curriculum talk which asserts the power of difference by applying the language of differentiation as the focus for inclusive pedagogical action. As the IPAA framework stresses, teachers must believe that they are qualified and capable of teaching all children. Teachers who are engaged in the IPAA in action continually develop creative new ways of working and their professional stance is one where they are willing to work with others (including all of their students) to continually enhance their professional learning through practise orientations. Hence, in this chapter, both the theoretical underpinnings of effective teaching associated with the cross-curriculum design are assumed to have a potential link to any one of the other curricular areas specified in this book. Cross-curriculum design inherently foregrounds inclusive pedagogical possibilities and a concern for knowing more about curriculum theorising and reimaging classroom practice for all students, that is engaging in generative and productive pedagogical work.

Despite their increasing importance in innovation, employment creation and economic growth, there is a dearth of theory-driven research on the financing and capital structure of new technology-based firms (NTBFs).¹ Hogan and Hutson (2005a) advance the High-Technology Pecking Order Hypothesis (HTPOH) to explain the role of equity in the financing of NTBFs in the software product sector. The HTPOH posits that NTBFs exhibit a hierarchical pattern of financing that gives precedence to internal sources, but if external financing is required, equity is preferred to debt. This study investigates the extent to which the genesis of the NTBF affects its financing patterns?

Within the framework of potential efforts and strategies to employment generation for young people in Africa in general and Ethiopia in particular, the agricultural sector is increasingly considered as an important sector and a valuable means for poverty reduction, the promotion of economic development, and youth's economic independence. Renewed hope is placed on the sector to offer sustainable livelihood prospects for the rural youth. Yet, the success and sustainability of the sector require a proper understanding of how households allocate youth labor time in the sector and whether agricultural labor supply is responsive to economic incentives such as shadow wages. Using gender- and age-specific plot-level panel data, we systematically analyze the impacts of shadow wages of each household member on youth agricultural labor supply across types of farms. The results indicate that agricultural shadow wages matter for the youth's labor supply in the sector, but the impact differs for male and female youth. We also show that trends and patterns of youth labor supply vary across gender and whether they work on their own farm, and so do their labor returns. The results are consistent after controlling for individual heterogeneity and instrumenting for possible endogeneity. Taking into account the intensity of youth's actual involvement in the family farm, own farm or off-farm work instead of their stated intentions, the results challenge the presumption that youth are abandoning agriculture, at least in agricultural potential areas of Ethiopia. Instead, the frequent narrative of youth disengaging from agriculture may be a result of methodological flaws or data limitations. The findings suggest that it is necessary to invest in agricultural development to enhance labor productivity and employability of young people in agriculture.

The chapter investigates: (1) Do married parents efficiently allocate time to children’s health care? (2) Are parents willing to sacrifice consumption for health improvements at an equal rate for all family members? (3) How does family structure affect health trade-offs parents make? (4) Are parental choices consistent with maximization of a single utility function?

A model is specified focusing on how parents allocate resources between consumption and goods that relieve acute illnesses for family members. Equivalent surplus functions measuring parental willingness to pay to relieve acute illnesses are estimated using data from a stated-preference survey.

Results provide limited support for the prediction that married parents allocate time to child health care according to comparative advantage. Valuations of avoided illness vary between family members and are inconsistent with the hypothesis that fathers’ and mothers’ choices reflect a common utility function.

Prior research on children’s health valuation has relied on a unitary framework that is rejected here. Valuation researchers have focused on allocation of resources between parents and children while ignoring allocation of resources among children, whereas results suggest significant heterogeneity in valuation of health of different types of children and of children in different types of households.

Results may provide a justification on efficiency grounds for policies to provide special protection for children’s health and suggest that benefit–cost analyses of policies affecting health should include separate estimates of the benefits of health improvements for children and adults.

Contemporary literature reveals that, to date, the poultry livestock sector has not received sufficient research attention. This particular industry suffers from unstructured supply chain practices, lack of awareness of the implications of the sustainability concept and failure to recycle poultry wastes. The current research thus attempts to develop an integrated supply chain model in the context of poultry industry in Bangladesh. The study considers both sustainability and supply chain issues in order to incorporate them in the poultry supply chain. By placing the forward and reverse supply chains in a single framework, existing problems can be resolved to gain economic, social and environmental benefits, which will be more sustainable than the present practices.

The theoretical underpinning of this research is ‘sustainability’ and the ‘supply chain processes’ in order to examine possible improvements in the poultry production process along with waste management. The research adopts the positivist paradigm and ‘design science’ methods with the support of system dynamics (SD) and the case study methods. Initially, a mental model is developed followed by the causal loop diagram based on in-depth interviews, focus group discussions and observation techniques. The causal model helps to understand the linkages between the associated variables for each issue. Finally, the causal loop diagram is transformed into a stock and flow (quantitative) model, which is a prerequisite for SD-based simulation modelling. A decision support system (DSS) is then developed to analyse the complex decision-making process along the supply chains.

The findings reveal that integration of the supply chain can bring economic, social and environmental sustainability along with a structured production process. It is also observed that the poultry industry can apply the model outcomes in the real-life practices with minor adjustments. This present research has both theoretical and practical implications. The proposed model’s unique characteristics in mitigating the existing problems are supported by the sustainability and supply chain theories. As for practical implications, the poultry industry in Bangladesh can follow the proposed supply chain structure (as par the research model) and test various policies via simulation prior to its application. Positive outcomes of the simulation study may provide enough confidence to implement the desired changes within the industry and their supply chain networks.

Supply chains deliver goods and services between shippers and receivers, covering collection, transportation, distribution as well as their handling and storage in between. In particular, transportation services are carried out by different transport modes. In some modern supply chains, different categories of air cargo carriers – combinations, freighter-only, and/or integrators – provide critical transport services.

This chapter develops a methodology for estimating the performance of supply chains served by an air cargo carrier network. The methodology is based on indicators of infrastructure use, technical/technological level, operational factors, economic factors, and environmental performance. This proposed methodology is applied to estimate performance of supply chains served by an integrated air cargo carrier – FedEx Express – operating a single hub in the US domestic air network. Results indicate that the methodology may be useful for estimation of overall supply chain performance under the condition that relevant data are available.