Probability proportional to size (πps) sampling using ranks

There can be gains in estimation efficiency over equal probability samplin methods when one makes use of auxiliary information for probability proporti onal to size with replacement (πpswr) sampling methods. The usual method is simple to execute, but might lead to more than one appearance in the sampl e for any particular unit. When a suitable variable x is not available, one may know how to rank units reasonably well relative to the unknown y values before sample selection. When such ranking is possible, we introduce a simple and efficient sampling plan using the ranks as the unknown x measures of size. The proposed sampling plan is similar to, has the simplicity of, and has no greater sampling variance than with replacement sampling, but is without replacement.     

Book reviews

Black Atlantic: Modernity and Double Consciousness, Paul Gilroy, Cambridge MA: Harvard University Press, October 1993.     

Travel Demand Management Targeting Reduced Private Car Use: Effectiveness, Public Acceptability and Political Feasibility

The private car is fast, comfortable, and convenient. However, worldwide massive car use causes serious environmental problems. Although breakthroughs in clean automobile technology may be under way, reducing car use seems necessary in order to achieve a sustainable transportation system. Several travel demand management (TDM) measures have therefore been proposed and some have been implemented with this aim. The article reviews research addressing the question of how effective, acceptable to the public, and politically feasible such measures are. The conclusion is that noncoercive TDM measures alone are unlikely to be effective in reducing car use. Therefore, coercive TDM measures such as increasing cost for or prohibiting car use may be necessary but are difficult to implement because of public opposition and political infeasibility. If combined with noncoercive TDM measures providing attractive travel alternatives and communicating the benefits of car-use reduction to the public, coercive TDM measures are likely to become more effective, acceptable, and politically feasible.     

Household consumption: Influences of aspiration level, social comparison, and money management

The present research posits and tests a model of household consumption of less necessary or luxury goods and services. It is hypothesized that a household's economic situation has a direct effect on this consumption as well as indirect effects mediated by aspiration level, social comparison and money management. Structural equation modeling of questionnaire data from a sample of households in a metropolitan area of Sweden (n=411) was used to test the model. The results reveal that as expected the household's economic situation has a significant direct effect on consumption and indirect effects through aspiration level and social comparison. The results also show that satisfaction with consumption increases with increased consumption and decreases with higher aspiration levels.     

Psychological and physiological stress responses during repetitive work at an assembly line

The association between psychological and physiological stress responses was examined in 20 male workers at an assembly line. Each worker was studied during a 2 h period on two consecutive days in their normal job and, in order to obtain physiological baseline values, during a corresponding paid 2 h period off the job on the third day. Self-reports of work demands, mood, etc., measurements of catecholamine and cortisol excretion and of systolic and diastolic blood pressure and heart rate were obtained at the end of each of the three 2 h periods. Work induced a significant elevation in almost all psychological and physiological measurements. Levels were consistently lower in workers reporting a 'good' workday compared to those reporting a 'normal' or a 'bad' day. Correlations between self-reports and physiological values showed that catecholamine and cortisol responses, respectively, tended to be associated selectively with different psychological conditions, catecholamine values being associated with feelings of time pressure and pressure by demands, cortisol values with irritation, tenseness and tiredness. The results show that perceived stress at an assembly line is consistently reflected in cardiovascular and neuroendocrine functions of the workers.     

Happiness and Satisfaction with Work Commute

Research suggests that for many people happiness is being able to make the routines of everyday life work, such that positive feelings dominate over negative feelings resulting from daily hassles. In line with this, a survey of work commuters in the three largest urban areas of Sweden show that satisfaction with the work commute contributes to overall happiness. It is also found that feelings during the commutes are predominantly positive or neutral. Possible explanatory factors include desirable physical exercise from walking and biking, as well as that short commutes provide a buffer between the work and private spheres. For longer work commutes, social and entertainment activities either increase positive affects or counteract stress and boredom. Satisfaction with being employed in a recession may also spill over to positive experiences of work commutes.     

Developing habitat models for waterbirds in urban wetlands: a log-linear approach

Up to 95% of wetlands in southwestern Ontario, Canada, have been drained and converted to other land uses since the mid-1800s. Remaining wetlands now exist within a mosaic of urban and agriculture land cover and may resemble “islands” from the point of view of species that need this habitat. We investigated the relationships between waterbirds and wetland size, isolation, and adjacent forest cover and roads in 19 wetlands within and adjacent to London, Ontario. Waterbirds were grouped into resource-based guilds: Dabblers, Divers, Waders, and Gulls and Terns (because of small samples, the Passerine and Raptor guilds were dropped from the statistical analyses). Because of the high degree of multicollinearity between variables, we used log-linear analysis to develop models that explained variations in species richness in the waterbird guilds. The log-linear technique provided quantification of environmental effects in a richer way than previous research as the interplay between biophysical factors found in reality are partially captured by the inclusion of interaction in the habitat models. All of the models incorporated the biophysical variables of wetland size and adjacent wetland area, forest cover, and roads. Waterbirds in these urban and near-urban landscapes appear to be using all wetlands available to them, no matter how small or how disjunct the wetland. This has implications for wetland evaluations that may not rate wetlands in human-dominated landscapes highly enough to be protected from development.     

Consumer attitudes towards switching supplier in three deregulated markets

The efficiency of deregulated markets is jeopardized by consumers failing to switch supplier to the extent that would be beneficial to them. In order to disentangle the determinants of failures to switch, the present study investigates consumers’ motives for negative attitudes towards switching in the deregulated Swedish markets for electricity, landline telecom, and home insurance. Based on the results of a mail survey of a random sample of 458 household consumers, reliable measures were constructed of attitude towards switching supplier, loyalty to the incumbent, information search costs to compare suppliers, and expected economic benefits from switching. A negative attitude towards switching supplier was shown to increase with loyalty, increase with information search costs and decrease with expected economic benefits. Attitude towards switching was more negative in the electricity market than in the other markets and more negative in the landline telecom market than in the home insurance market. The differences between markets were accounted for by differences in loyalty, information search costs, and expected economic benefits.     

The state and voluntary social work in Sweden

If Sweden has been considered at all within the voluntary research tradition, it is mainly in terms of providing a state-dominated contrast to countries where the sector is said to flourish. This article questions this rather one-sided picture of Sweden, which seems to rest on weak empirical grounds, especially if the voluntary sector as a whole is analysed. The main focus of the article is, however, on social services. It is shown that, from a historical perspective, co-operation between the state and the voluntary sector seems to be a distinctive feature of Sweden, even during periods of government take-over of voluntary activities. Today the relations between the voluntary sector and the state appear to be changing to a situation in which associations are taking part in the production of welfare services to a larger extent than heretofore.