Improving the accuracy and operational predictability of project cost forecasts: an adaptive combination approach

Conducting an early warning forecast to detect potential cost overrun is essential for timely and effective decision-making in project control. This paper presents a forecast combination model that adaptively identifies the best forecast and optimises various combinations of commonly used project cost forecasting models. To do so, a forecast error simulator is formulated to visualise and quantify likely error profiles of forecast models and their combinations. The adaptive cost combination (ACC) model was applied to a pilot project for numerical illustration as well as to real world projects for practical implementation. The results provide three valuable insights into more effective project control and forecasting. First, the best forecasting model may change in individual projects according to the project progress and the management priority (i.e. accuracy, outperformance or large errors). Second, adaptive combination of simple, index-based forecasts tends to improve forecast accuracy, while mitigating the risk of large errors. Third, a post-mortem analysis of seven real projects indicated that the simple average of two most commonly used cost forecasts can be 31.2% more accurate, on average, than the most accurate alternative forecasts.     

A Case Study Evaluating the Risk of Infection from Middle Eastern Respiratory Syndrome Coronavirus (MERS‐CoV) in a Hospital Setting Through Bioaerosols

Middle Eastern respiratory syndrome, an emerging viral infection with a global case fatality rate of 35.5%, caused major outbreaks first in 2012 and 2015, though new cases are continuously reported around the world. Transmission is believed to mainly occur in healthcare settings through aerosolized particles. This study uses Quantitative Microbial Risk Assessment to develop a generalizable model that can assist with interpreting reported outbreak data or predict risk of infection with or without the recommended strategies. The exposure scenario includes a single index patient emitting virus‐containing aerosols into the air by coughing, leading to short‐ and long‐range airborne exposures for other patients in the same room, nurses, healthcare workers, and family visitors. Aerosol transport modeling was coupled with Monte Carlo simulation to evaluate the risk of MERS illness for the exposed population. Results from a typical scenario show the daily mean risk of infection to be the highest for the nurses and healthcare workers (8.49 × 10^?4 and 7.91 × 10^?4, respectively), and the lowest for family visitors and patients staying in the same room (3.12 × 10^?4 and 1.29 × 10^?4, respectively). Sensitivity analysis indicates that more than 90% of the uncertainty in the risk characterization is due to the viral concentration in saliva. Assessment of risk interventions showed that respiratory masks were found to have a greater effect in reducing the risks for all the groups evaluated (>90% risk reduction), while increasing the air exchange was effective for the other patients in the same room only (up to 58% risk reduction).     

Do Young Children's Representations of Discipline and Empathy Moderate the Effects of Punishment on Emotion Regulation?

This study examined whether children's representations of parenting (perceptions of authoritative discipline and empathy) moderated the association between harsh punishment—including corporal punishment (CP) and verbal punishment (VP)—and children's emotion regulation at the age of five years. Participants were 559 low‐income mother‐child dyads. Maternal self‐reports and home observations were used to measure punishment. Children's representations were assessed using the MacArthur Story Stem Battery. Children's emotion regulation was assessed by observer rating via the Leiter International Performance Scale–Revised. Hierarchical multiple regressions revealed that children's authoritative disciplinary representations moderated the effects of both VP and CP on children's emotion regulation. Empathic representations moderated the effects of VP only on children's emotion regulation. The current findings highlight the role of children's internal representations as potential protective factors in the context of harsher forms of punishment.     

Local Control Strategy: Simple Analyses of Air Pollution Data Can Reveal Heterogeneity in Longevity Outcomes

Claims from observational studies that use traditional model specification searches often fail to replicate, partially because the available data tend to be biased. There is an urgent need for an alternative statistical analysis strategy, that is not only simple and easily understood but also is more likely to give reliable insights when the available data have not been designed and balanced. The alternative strategy known as local control first generates local, nonparametric effect‐size estimates (fair treatment comparisons) and only then asks whether the observed variation in these local estimates can be predicted from potential confounding factors. Here, we illustrate application of local control to a historical air pollution data set describing a “natural experiment” initiated by the federal Clean Air Act Amendments of 1970. Our reanalysis reveals subgroup heterogeneity in the effects of air quality regulation on elderly longevity (one size does not fit all), and we show that this heterogeneity is largely explained by socioeconomic and environmental confounders other than air quality.     

Subjective Well-Being and Life Satisfaction in the Kingdom of Tonga

This paper describes an initial attempt to assess the subjective well being of a sample of 227 Tongans via self-report. Using items adapted from the Subjective Well Being Inventory (SUBI; Nagpal and Sell, 1985; Sell and Nagpal, 1992), participants rated their level of overall life satisfaction along with their perceptions of well-beingin a number of other more specific life domains. Results indicated that mean ratings of global life satisfaction were generally positive. A factor analysis of the remaining domain-specific well-being items indicated that items loaded on to one of two factors dealing with overall positive or negative evaluations of these life areas. Importantly, these scale items stressed the importance of social and kin relations in contributing to overall well-being. In terms of demographic variables, mature respondents reported greater levels of overall life satisfaction and well-being as compared to youthful respondents. Implications and directions for future research are discussed.     

Pitfalls in comparing immigrants with the Australian-born population with particular reference to socioeconomic status

With the increasing interest in the impact of immigration on the character of the Australia’s population it is useful to draw attention to the differences that can occur when comparisons of the immigrant and the host population with respect to socioeconomic status are based on aggregate rather than on disaggregate measures. In this paper the discussion focuses on the implications of not disaggregating by age and sex, with respect to such variables as: post-school qualifications, occupation, and labour-force participation, using the total overseas-born population in Australia as an example. The analysis demonstrates the fact that the different age structures of the immigrant and the host populations can result in deficiencies in the aggregate rates.     

Popular cinema and lesbian interpretive strategies

In its examination of the relationship between popular film and lesbian viewing practices, this study attempts to more fully elucidate current ideas around audience engagement and forms of cultural reception. Drawing on 15 in-depth interviews conducted in Western Canada in 1996, the results clearly demonstrate the existence of active lesbian viewers, whose interpretations of popular film are intimately informed by lesbian-specific life experiences and cultural competencies. Although the social conditions which create the need for resistant viewing are themselves oppressive, subversion of mainstream film holds out some possibility of empowerment for lesbian viewers.