Estimating mean exposures from censored data: exposure to benzene in the Australian petroleum industry

A retrospective assessment of exposure to benzene was carried out for a nested case control study of lympho-haematopoietic cancers, including leukaemia, in the Australian petroleum industry. Each job or task in the industry was assigned a Base Estimate (BE) of exposure derived from task-based personal exposure assessments carried out by the company occupational hygienists. The BEs corresponded to the estimated arithmetic mean exposure to benzene for each job or task and were used in a deterministic algorithm to estimate the exposure of subjects in the study. Nearly all of the data sets underlying the BEs were found to contain some values below the limit of detection (LOD) of the sampling and analytical methods and some were very heavily censored; up to 95% of the data were below the LOD in some data sets. It was necessary, therefore, to use a method of calculating the arithmetic mean exposures that took into account the censored data. Three different methods were employed in an attempt to select the most appropriate method for the particular data in the study. A common method is to replace the missing (censored) values with half the detection limit. This method has been recommended for data sets where much of the data are below the limit of detection or where the data are highly skewed; with a geometric standard deviation of 3 or more. Another method, involving replacing the censored data with the limit of detection divided by the square root of 2, has been recommended when relatively few data are below the detection limit or where data are not highly skewed. A third method that was examined is Cohen's method. This involves mathematical extrapolation of the left-hand tail of the distribution, based on the distribution of the uncensored data, and calculation of the maximum likelihood estimate of the arithmetic mean. When these three methods were applied to the data in this study it was found that the first two simple methods give similar results in most cases. Cohen's method on the other hand, gave results that were generally, but not always, higher than simpler methods and in some cases gave extremely high and even implausible estimates of the mean. It appears that if the data deviate substantially from a simple log-normal distribution, particularly if high outliers are present, then Cohen's method produces erratic and unreliable estimates. After examining these results, and both the distributions and proportions of censored data, it was decided that the half limit of detection method was most suitable in this particular study.

Artikel 3(1) en (2) van die Mineral and Petroleum Resources Development Act 28 van 2002: 'n herbeskouing

Sections 3(1) and 3(2) of the Mineral and Petroleum Resources Development Act 28 of 2002
This contribution entails a discussion of the impact of section 3 of the Mineral and Petroleum Resources Development Act on various aspects of the new mineral and petroleum law. At the core of the discussion is the question of how this section is interpreted by various commentators, and the implications of the different opinions on the application of the section. The initial discussion highlights problems with the new definition of a "mineral": Soil, including topsoil is at present included in die definition of a "mineral" in the act. The definition should be rectified by the legislature as it has far-reaching consequences in respect of the extent of the state's power in terms of section 3(2) of the act to grant entitlements in respect of minerals, including topsoil. The implications of section 3 for the control and management of minerals are discussed and placed in the context of the question about the constitutionality of the act. It is argued that legislative guidance is urgently needed to clarify continuing uncertainty, caused by sloppy drafting and different opinions about the connection between private law and public law in relation to minerals and the actual position of existing right holders.

Perceived environmental aesthetics and convenience and company are associated with walking for exercise among Australian adults

Background: This study aimed to investigate relationships between environmental aesthetics, convenience, and walking companions and walking for exercise or recreation and to investigate differences in these relationships by sex and by reported physical and mental health.

Methods: Analyses of cross-sectional self-report data from a statewide population survey of 3,392 Australian adults were used.

Results: Men and women reporting a less aesthetically pleasing or less convenient environment were less likely to report walking for exercise or recreation in the past 2 weeks. Those respondents, particularly women, reporting no company or pet to walk with were also less likely to walk for exercise or recreation. Associations with environmental and social influences were observed for men and women reporting both good and poor physical and mental health.

Conclusions: Perceived environmental aesthetics and convenience and walking companions are important correlates of walking for exercise among urban Australians. Acknowledging the cross-sectional nature of these data, findings support a case for evaluation of environmental policies to promote physical activity.

An examination of the joint venture market entry option in China : a case study of an Australian company's international marketing experience in China

There is a widely held view in the literature that foreign companies looking to invest in the China market should opt for joint ventures rather than wholly foreign-owned enterprises for many reasons, ranging from a smaller capital commitment to utilising the market knowledge of local Chinese partners. This paper examines this issue in the light of the experience of the Foster's Brewing Group which established three joint ventures in China only to reject this form of market entry option within a few years. The paper looks at some of the reasons behind Foster's rejection of the joint venture option and proposes some key guidelines that foreign companies should follow if they are to successfully establish joint ventures in China.

Managers' views on ABC in an insurance company: A grounded theory case study

This is an in-depth case study using a grounded theory approach to explore managers’ views of ABC as part of the control system in an insurance company. Relevant issues are allowed to emerge from the data rather than imposing a theoretical framework upon them. Hypotheses are derived rather than confirmed. Issues emerging from this case study include: the relevance of ABC to managers, increased cost awareness coupled with the problem of taking qualitative factors into account, and the existence of different perceptions of managers within the same department. One hypothesis is how an understanding of ABC can affect job satisfaction by influencing the impact of ABC on managers’ actions. In this case study process and non-process managers had different levels of understanding and use of ABC information. A second hypothesis is that how managers view ABC information depends on whether they adopt a personal or an organisational perspective.

Removal of company directors in a climate of corporate collapses

The string of high-profile corporate collapses recently has provided a fresh insight into many important topics and issues in Australian corporations law. Notwithstanding this, one topic that continues to receive inadequate attention both in Australia and in foreign jurisdictions is the statutory removal of  directors. In an earlier article published in this journal, one of the present authors contributed towards addressing this lack of commentary on the topic by highlighting a number of peculiarities with the provisions under the then Corporations Law regulating the removal of directors in public and proprietary companies. Since that time, the CLERP amendments to the Corporations Law (now Corporations Act 2001) in 2000 introduced some interesting changes to the provisions dealing with the removal of directors in public and proprietary companies. In this article, the authors provide an explanation and critical analysis of these changes, and consider the recent Western Australian Supreme Court decision of Allied & Mining Process Ltd v Boldbow Pty Ltd [2002] WASC 195, which deals with some of the issues raised by the authors in relation to the CLERP amendments. According to the authors, whilst some of the peculiarities raised in the earlier article no longer exist post-CLERP, the current removal provisions still raise some important questions of interpretation.

Macleod and the offence of defrauding the company in one-person businesses: the divergence between legal principle and logic widens

The recent High Court decision in Macleod v R establishes that a director and sole shareholder may be convicted of fraudulently applying a company's property even though the person has consented to the personal use of the company's property. It is contended that while this decision is consistent with the weight of precedent, it is wrong in principle. The decision implies that corporations are not only separate legal entities, but that they are highly virtuous legal entities -- incapable of being imbued with the dishonest intentions and activities of the individuals controlling the company.

Why all directors should be shareholders in the company: the case against "independence"

It is argued that the shift towards more 'independent' directors, in the wake of corporate collapses, is a fundamentally bad move, undermining the rights and powers of minority shareholders - entrenches a second-rate corporate governance model, separation of ownership and control, in company law - rather than suggest cosmetic reform in an attempt to address the problem, it is proposed that all directors must have significant interest in the company they serve - directors' self-interests and the best interests of the company become intertwined - this is a more effective way of tackling the problem of separation of ownership and control

Corporate donations, the best interest of the company and the proper purpose doctrine

Corporate philanthropy is illegitimate spending by powerful corporate elite of someone else’s money; an attempt to bypass democratic allocation of taxes; philanthropy by individuals is laudable, but not by corporations.

Just as I wouldn’t want you to implement your personal judgments by writing checks on my bank account for charities of your choice, I feel it inappropriate to write checks on your corporate ‘bank account’ for the charities of my choice.