The Prospects for Digital Radio

Digital audio broadcasting is a major innovation in radio, one that is at its most advanced in Europe. It has the potential to deliver high-quality audio reception and to increase significantly the capacity of the radio spectrum, with the possibility of an expansion of both the range and diversity of radio programming. Nevertheless, in the UK and elsewhere it remains relatively unknown and under-adopted in comparison with other consumer technologies like digital television. This article examines the origins of digital radio, and considers how this technology is expected to become a mass communications technology, eventually supplanting analogue radio. However, in its present form, there is little that is novel currently being offered on digital radio, and the economic and political contexts in which it is being developed may encourage further concentration of ownership and reduce diversity of choice in listening. Unlike previous innovations then, such as FM broadcasting, there appear to be few compelling advantages of digital radio that will persuade listeners to adopt this new technology. If this new technological system is to succeed, alternative uses must be found for it, and one area for which it might be suited is mobile data communications. The article concludes by suggesting that this might mean that radio becomes of secondary importance to this potentially lucrative application of digital audio broadcasting technology.     

Quality of life indicators and program evaluation

Social indicators and program evaluation research have much in common. Quality of life work specifically raises the question of objective versus subjective variables, aggregate data versus distributional and individual issues, and the reference standards used in judgment and evaluation decisions. This article presents perspectives on these issues from the orientation of quality of life research and proposes that these approaches have relevance for program evaluation work.     

The influence of contextual variables on interpersonal spacing

Four studies examined the effects of contextual variables on interpersonal spacing. Contextual variables were defined as transitory factors that involved the setting in which an interaction occurs; these variables were delineated from personal and interpersonal characteristics. In each experimental setting, white male subjects were allowed to choose the distance at which they interacted with a stranger. The first study found that subjects who had experienced social isolation prior to the interaction chose greater distances than subjects who had not been isolated. The second study found that subjects chose greater distances when they believed their interaction would be observed by others than when the interaction was private. Results from the third study yielded an interaction between topic of conversation and expected length of conversation with greatest distance being chosen when subjects expected a long conversation to focus on a personal topic. In the final study, room size and shape influenced interpersonal distance; the interaction indicated that room size affected distance only in rectangular rooms. The results are discussed in terms of equilibrium model (Argyle & Dean, 1965). It is argued that contextual variables affect intimacy, and that the equilibrium model can explicate the effects of contextual as well as personal and interpersonal variables.The help of the following people in conducting the research and analyzing the data is gratefully acknowledged: Elizabeth Brown, Brad Reeves, Michael Satir, Sheryl Vaughn, Mary Holland, Quig Lawrence, William Webb, and Kerry Marsh. Thanks are also in order for an unusually thorough reviewer who raised a number of important issues.     

Comparative Potency Method for Cancer Risk Assessment: Application to Diesel Particulate Emissions1

An estimation of the human lung cancer “unit risk” from diesel engine particulate emissions has been made using a comparative potency approach. This approach involves evaluating the tumorigenic and mutagenic potencies of the particulates from four diesel and one gasoline engine in relation to other combustion and pyrolysis products (coke oven, roofing tar, and cigarette smoke) that cause lung cancer in humans. The unit cancer risk is predicated on the linear nonthreshold extrapolation model and is the individual lifetime excess lung cancer risk from continuous exposure to 1 μg carcinogen per m³ inhaled air. The human lung cancer unit risks obtained from the epidemiologic data for coke oven workers, roofing tar applicators, and cigarette smokers were, respectively, 9.3 × 10^?4, 3.6 × 10^?4, and 2.2 × 10^?6 per μg particulate organics per m³ air. The comparative potencies of these three materials and the diesel and gasoline engine exhaust particulates (as organic extracts) were evaluated by in vivo tumorigenicity bioassays involving skin initiation and skin carcinogenicity in SENCAR mice and by the in vitro bioassays that proved suitable for this analysis: Ames Salmonella microsome bioassay, L5178Y mouse lymphoma cell mutagenesis bioassay, and sister chromatid exchange bioassay in Chinese hamster ovary cells. The relative potencies of the coke oven, roofing tar, and cigarette smoke emissions, as determined by the mouse skin initiation assay, were within a factor of 2 of those determined using the epidemiologic data. The relative potencies, from the in vitro bioassays as compared to the human data, were similar for coke oven and roofing tar, but for the cigarette smoke condensate the in vitro tests predicted a higher relative potency. The mouse skin initiation bioassay was used to determine the unit lung cancer risk for the most potent of the diesel emissions. Based on comparisons with coke oven, roofing tar, and cigarette smoke, the unit cancer risk averaged 4.4 × 10^?4. The unit lung cancer risks for the other, less potent motor-vehicle emissions were determined from their comparative potencies relative to the most potent diesel using three in vitro bioassays. There was a high correlation between the in vitro and in vivo bioassays in their responses to the engine exhaust particulate extracts. The unit lung cancer risk per μg particulates per m³ for the automotive diesel and gasoline exhaust particulates ranged from 0.20 × 10^?4 to 0.60 × 10^?4; that for the heavy-duty diesel engine was 0.02 × 10^?4. These unit risks provide the basis for a future assessment of human lung cancer risks when combined with human population exposure to automotive emissions.     

Multi-valued strategy-proof social choice rules

In this paper we introduce a new definition of strategy-proofness for multi-valued social choice correspondences. We prove two Gibbard-Satterthwaite type results for strategy-proof social choice correspondences. These results show that allowing multiple outcomes as social choices will not necessarily lead to an escape from the Gibbard-Satterthwaite impossibility theorem. Received: 24 January 2001/Accepted: 19 March 2001     

The Texaco racial discrimination case and shareholder wealth

We analyze the wealth ejfects of the Texaco racial discrimination lawsuit both on the shareholders of Texaco and its major U.S. competitors. Employing a comprehensive data set which included every case docket entry and every Wall Street Journal article on the case as an experimental stimulus, our findings suggest that the overall cost of the case to Texaco shareholders exceeded $500 million, that Texaco's tribulations had little, if any, impact on the share prices of its major competitors, and that Wall Street Journal coverage of the case was highly correlated with significant changes in Texaco stock prices. This last finding provides significant support for Hite 's suppostion that newspaper editors “key ” on ex post stock price changes in selecting the events to be covered in the next day's edition. The authors are grateful to Kee Chung for helpful comments on earlier drafts and also acknowlege the help-ful assistance of the staff of the law library at the Cecil C. Humphreys School of Law at The University of Memphis.     

Childhood Developmental Risk for Teen Childbearing in Britain

Adolescence is often assumed to be the most important period of life for understanding teen childbearing risk. Developmental perspectives challenge that assumption, offering the possibility that early childhood characteristics may have unique and lasting effects on the risk for teen childbearing. This study examined family life risk factors (socioeconomic status, family stress, and parental involvement in education) and how their effects on teen childbearing risk varied, depending on the childhood age at which they were experienced. Prospective life history data from the National Child Development Study of Great Britain were used to study a birth cohort of 4,928 British women, 15.3% of who became pregnant as teens. This study demonstrated that data from early childhood significantly contribute to the understanding of teen childbearing risk.