Introduction

Empirical studies of occupational structure in South Africa have tended to be unsatisfactory, detailed work on small sectors of the economy coexisting with across‐the‐board studies too crudely aggregated to allow for a precise assessment of a changing situation. This study presents the results of an analysis by ‘race’ into 14 occupational groups of South African employment outside agriculture, domestic service and the informal sector over the period 1969 to 1977. It argues that over the period there has been a definite increase in the share of owner I manager and, more particularly, petty bourgeois occupations, with a corresponding decline in the proportion of unskilled workers. It also suggests that changes in the ‘racial’ division of labour are more complex than has sometimes been supposed.     

Using Split-Population Models to Examine Predictors of the Probability and Timing of Parity Progression

Survival models are widely used in demography to analyse the timing of events such as death or leaving school. However, for events such as marriage or childbirth that are not experienced by everyone, standard survival analysis conflates the speed of progressing to an event with the proportion that never experience the event. The problem can be overcome by applying a ‘split population’ or ‘cure’ survival time model which splits the population into those who eventually experience the event and those who do not, and determines the speed of progression for the former. This paper demonstrates the use of split-population models in examining variables which affect the propensity and timing of additional births. The data analysed are from a sample of women from the 2001 Household, Income and Labour Dynamics in Australia (HILDA) Survey (N = 4,611). We model the propensity and time to have another child given sex composition of existing children, number of siblings and age at first birth for three cohorts of women. The study finds evidence of a preference for a mixed-sex composition, and an increased propensity for women with two boys to try for a third child. Women in later cohorts tend to have more children if they themselves come from larger families. Age at first birth is strongly associated with the propensity to have another child and with the speed of progression.     

The Political Economy of City Formation in California: Limits to Tiebout Sorting

Objective . This paper analyzes the extent to which voter behavior in city formation elections supports Tiebout's (1956) hypothesis that residential sorting facilitates efficiency of local service provision. It develops a two-stage model of city formation to distinguish agenda setting from voter outcomes on city formation proposals. Methods . Logit analysis is used to analyze voting in 71 city formation elections, incorporating Heckman's two-stage procedure to correct for self-selection of local referenda. Results . Community fiscal and demographic factors influence agenda setting more than voting behavior. Wealthier communities in high-growth counties are more likely to propose formation of a city. In contrast, community characteristics have little influence on electoral outcomes, suggesting that boundedly rational voters rely on information heuristics. Conclusions . Although reduction of diversity did not appear to motivate city formation, sorting around residential income, land use preferences, and other demographic variables may facilitate relative efficiency of service provision.     

Transforming into the new era: public relations industry in Hong Kong and China

The public relations industry as one of the key industries in Hong Kong has metamorphosed into a new phase after the resumption of sovereignty to China. Based on in-depth interviews with eight experienced corporate communication practitioners from multi-national and sizeable local corporations in Hong Kong and China, the study traces the recent development of public relations and/or corporate communication (hereafter PR/CC) highlighting issues of role and function, language and communication strategy, and ethics and professionalism.     

Handling the effect of non-response in graphical models for longitudinal data

In this paper we investigated the use of attrition weights to cope with non-response when selecting graphical chain models for longitudinal data. We proposed a parametric bootstrap approach to account for the extra variability introduced by the estimation of the weights and compared this with results using standard test procedures.     

Vulnerable children's health as described in investigations of reported children

This study explores whether the social services weigh in health aspects, and what these may be, when investigating reported children's life situation. Information about physical and psychological health aspects for 259 children in 272 investigations was included. Overall, information about children's health was limited. Problematic emotions were the most commonly reported health aspect in the investigations, whereas suicidal thoughts, self‐harm behaviour and gastrointestinal and renal diseases were mentioned least of all. A cluster analysis revealed that the low level of health information group included the largest sample of data and consisted of investigations with minimal information about children's health. The three other cluster groups, Neurological diseases and psychosomatic symptoms, Emotional health and Physical and psychological health and destructive behaviour, consisted of investigations conducted mostly according to the model called Children's Needs In Focus (BBIC, in Swedish, Barns Behov i Centrum). Although these investigations also produced limited information, they provided more than those assessed as having a low level of information about health aspects. The conclusion is that it is necessary to increase information about health aspects in investigations if social welfare systems are to be able to fulfil their ambition of supporting vulnerable children's need of health care.     

Computing maximum upward planar subgraphs of single-source embedded digraphs

We show how to compute a maximum upward planar single-source subgraph of a single-source embedded DAG G _φ . We first show that finding a maximum upward planar subgraph of a single-source embedded digraph is NP-complete. We then give a new characterization of upward planar single-source digraphs. We use this characterization to present an algorithm that computes a maximum upward planar single-source subgraph of a single-source embedded DAG. This algorithm takes O(n ⁴) time in the worst case and O(n ³) time on average.     

Estimating a distribution for each category of a sensitive variate

The use of a Randomized Response (RR) design makes it possible to estimate the distribution of a sensitive variate. In this paper, the estimation of the distribution of a non-sensitive variate for each category of a sensitive variate is considered for the case where data on the sensitive variate is obtained by use of an RR procedure. Simple estimators are developed without making any distributional assumptions about the non-sensitive variate. However, if distributional assumptions are made, it is shown that the EM algorithm may be used to compute Maximum Likelihood estimates. Computational comparisons of the estimators, using simulation, indicate that the simple estimators perform well, particularly for large sample sizes.     

Systematic Integration of Consumer Input into Curriculum Revision

This paper employs Lippitt, Watson, and Wesley's perspective of planned change to analyze the curriculum revision efforts of faculty at the University of Wisconsin-Madison from 1969 to 1973. It is the consensus of the authors that it is possible and appropriate to apply the same motions we commonly associate with “good social work practice” to curriculum revision. Each of the phases of change is examined analytically and behaviorally from the standpoint of actions which occurred during that phase. The result of the change process was the acceptance of a new structural model within which to build curriculum.