Bayesian Graphical Models for STructural Vector Autoregressive Processes

This paper proposes a Bayesian, graph‐based approach to identification in vector autoregressive (VAR) models. In our Bayesian graphical VAR (BGVAR) model, the contemporaneous and temporal causal structures of the structural VAR model are represented by two different graphs. We also provide an efficient Markov chain Monte Carlo algorithm to estimate jointly the two causal structures and the parameters of the reduced‐form VAR model. The BGVAR approach is shown to be quite effective in dealing with model identification and selection in multivariate time series of moderate dimension, as those considered in the economic literature. In the macroeconomic application the BGVAR identifies the relevant structural relationships among 20 US economic variables, thus providing a useful tool for policy analysis. The financial application contributes to the recent econometric literature on financial interconnectedness. The BGVAR approach provides evidence of a strong unidirectional linkage from financial to non‐financial super‐sectors during the 2007–2009 financial crisis and a strong bidirectional linkage between the two sectors during the 2010–2013 European sovereign debt crisis. Copyright © 2015 John Wiley & Sons, Ltd.     

The welfare cost of means‐testing: pensioner participation in income support

We estimate parametric and semi‐parametric binary choice models of benefit take‐up by British pensioners and use a revealed preference argument to infer the cash‐equivalent value of disutility arising from stigma or complexity of the claims process. These implicit costs turn out to be relatively small, averaging about £3–4 per week across Income Support recipients. Using the Foster–Greer–Thorbecke measure of poverty among pensioners, we find that allowing for implicit claim costs incurred by benefit recipients raises the measured degree of poverty by not more than 13%. Copyright © 2007 John Wiley & Sons, Ltd.     

Estimating the time involved in managing the 'unoccupied bed:' a time and motion study

Occupied bed days are often used as a demand indicator when calculating the number of nurses required to provide safe care. However, such calculations fail to take into account the amount of nursing time consumed by the "unoccupied bed." This study used direct observation time-and-motion methods to estimate the time and costs associated with a bed that is unoccupied. The average time taken to complete all of the activities associated with a bed that was unoccupied due to an internal transfer was 8.65 minutes, for a patient discharge 26.27 minutes, and for a patient admission 37.7 minutes. An average daily cost for activities surrounding these patient movements was approximately $386/day (AUD) in registered/enrolled nursing salaries alone. The unoccupied bed is not resource neutral and time associated with its maintenance should be considered when calculating nursing requirements to provide safe care.     

The evolution of the Australian life insurance industry

The life insurance industry in Australia has traditionally been an important source of long term finance for both the public and private sector. However, very little historical analysis has been undertaken into an industry that constitutes a fundamental part of the economy's financial sector. The present climate of deregulation has initiated an irrevocable process of change within the industry. To comprehend the full implications of this change it is necessary to have an understanding of how the industry has evolved. This paper seeks to provide a background account of the growth of the life insurance industry in Australia highlighting the influences that have determined the structure of the industry.     

Adaptation and change in the Australian life insurance industry: an historical perspective

In the wake of the deregulation of the financial sector in Australia in the 1980s and 1990s the life insurance industry has undergone a period of rapid change and reorganisation. Part of this adjustment has been the move towards the integration of financial service provision and the rise of bancassurance. This paper investigates the strategies adopted by Australian life insurers as they moved into the increasingly competitive environment triggered by the lifting of government restrictions on banking practices. It compares the approach of life insurers with that adopted in an earlier period of expansion and change. During the 1950s and 1960s an influx of foreign owned insurance companies into the Australian market precipitated the diversification of domestic life insurers into other insurance markets. The catalyst for change in both cases was the change in information costs brought about by the change in the competitive environment. The experience of the Australian life insurance market would suggest that there is a link between changing information costs and changing organisational structures. However this link is circumscribed by the institutional environment.     

Do rainfall conditions push or pull rural migrants: evidence from Malawi

This article uses nationally representative data from Malawi's 2004/05 Integrated Household Survey (IHS2) to examine whether rainfall conditions influence a rural worker's decision to make a long‐term move to an urban or another rural area. Results of a Full Information Maximum Likelihood regression model reveal that (1) rainfall shocks have a negative association with rural out‐migration, (2) migrants choose to move to communities where rainfall variability and drought probability are lower, and (3) rainfall shocks have larger negative effects on the consumption of recent migrants than on the consumption of long‐time residents.     

Delineation of Source Protection Zones Using Statistical Methods

Source protection zones are increasingly important for securing the long-term viability of drinking water derived from groundwater resources. These may be either time-related capture zones or catchments related to the activity of a pumping well or spring. The establishment of such zones is an indispensable measure for the proper assessment of groundwater resource vulnerability and reduction of risk, which may be induced by human activities. The delineation of these protection zones is usually performed with the aid of models, which are in turn based on site-specific information of the aquifers geometry, hydraulic parameters and boundary conditions. Owing to the imperfect knowledge of such information, predicting the location of these zones is inherently uncertain. It is possible to quantify this uncertainty in a statistical manner through the development of probability maps, which shows the probability that a particular surface location belongs to the aquifers capture zone (or catchment area). This publication aims at the investigation of the requirements for the establishment of probabilistic source protection zones, the practical use of stochastic methods in their delineation, and the use of data-assimilation for uncertainty reduction. It also provides a methodology for the implementation of these methods by modelling practitioners.     

The Development of the Institutional Investor: The Case of Australian Life Insurers 1945–85

This paper considers the post‐war development of asset management practices among Australian life insurers, which have historically been among the largest institutional investors in Australia. A complex process of adaptation and organisational restructuring allowed life insurers to transform from basic investors of policy‐holders’ funds to large multifaceted institutional investors in just three decades. Three stages in the development of investment practices are identified. These phases trace the process of expanding existing knowledge bases; diversification; and the acquisition of new skills; consolidation and the integration of these skills into institutional structures; thus completing one cycle of organisational learning and setting the stage for the next.