Some indications for professional development in social work: a study of theoretical interest and attitudes towards research among Icelandic social workers

This study among Icelandic social workers generally showed positive attitudes towards research activity in the field. Most respondents, whereof half were practice teachers, saw the practicum as an important tool for the integration of theoretical application and research activity to practice. Almost all saw research activity as a feasible way to empower social work as a profession. Simultaneously, a relatively small percentage report their own research activity. Besides this discrepancy some interesting differences were found according to number of years after graduation, field employment and experience as practice teachers. It is argued that the theme in focus is a critical indication of professional development and highly relevant for the educational discourse as for future professional development.     

Does digitization lead to the homogenization of cultural content?

Using weekly music charts data in 10 countries over the period 1990–2015, we analyze whether digitization leads to a trend of homogenization of music content or conversely to a greater acoustic disparity. We split the digitization era in four periods that correspond to four new emblematic distribution models (Napster, iTunes, YouTube, Spotify). Our main result is that while acoustic diversity decreased during the iTunes and the YouTube periods, the period that begins with the introduction of audio streaming services, such as Spotify, represents a turning point and is marked by a significant increase in acoustic diversity.     

Decision-Making, Time Horizons, and Risk in the Very Long-Term Perspective

Some decisions made today have far-reaching consequences as exemplified by those concerning nuclear power and spent nuclear fuel. The investigation presented here uses a decision theoretic framework in which time horizons and the discounting of negative consequences play significant roles. The results indicated wide variations in the lengths of the planning horizons judged to be adequate not only across a number of activities, including nuclear waste management, but also across groups of subjects (e.g., engineering students, retired people, and nuclear fuel experts). The paper reports typical judgments and correlations between different variables for different groups of subjects. The differences across groups reflect potential sources of conflict, depending in part on different values and different perceptions of more or less uncertain facts. Discounting functions for negative consequences in the future were also established. A range in differences in the speed of discounting were found and illustrated. Furthermore, it was found that substantial proportions in all groups regarded negative consequences related to nuclear waste as nondiscountable. When asked about the effect of time until outcome on acceptable probability of a negative outcome, many subjects used the probability concept in an incoherent way, illustrating the great difficulty in communicating small probabilities in a long-term risk context.     

Risk Mapping of Groundwater‐Drawdown‐Induced Land Subsidence in Heterogeneous Soils on Large Areas

Groundwater leakage into subsurface constructions can cause reduction of pore pressure and subsidence in clay deposits, even at large distances from the location of the construction. The potential cost of damage is substantial, particularly in urban areas. The large‐scale process also implies heterogeneous soil conditions that cannot be described in complete detail, which causes a need for estimating uncertainty of subsidence with probabilistic methods. In this study, the risk for subsidence is estimated by coupling two probabilistic models, a geostatistics‐based soil stratification model with a subsidence model. Statistical analyses of stratification and soil properties are inputs into the models. The results include spatially explicit probabilistic estimates of subsidence magnitude and sensitivities of included model parameters. From these, areas with significant risk for subsidence are distinguished from low‐risk areas. The efficiency and usefulness of this modeling approach as a tool for communication to stakeholders, decision support for prioritization of risk‐reducing measures, and identification of the need for further investigations and monitoring are demonstrated with a case study of a planned tunnel in Stockholm.     

A Bias–Reduced Log–Periodogram Regression Estimator for the Long–Memory Parameter

In this paper, we propose a simple bias–reduced log–periodogram regression estimator, ^d_r, of the long–memory parameter, d, that eliminates the first– and higher–order biases of the Geweke and Porter–Hudak (1983) (GPH) estimator. The bias–reduced estimator is the same as the GPH estimator except that one includes frequencies to the power 2k for k=1,…,r, for some positive integer r, as additional regressors in the pseudo–regression model that yields the GPH estimator. The reduction in bias is obtained using assumptions on the spectrum only in a neighborhood of the zero frequency. Following the work of Robinson (1995b) and Hurvich, Deo, and Brodsky (1998), we establish the asymptotic bias, variance, and mean–squared error (MSE) of ^d_r, determine the asymptotic MSE optimal choice of the number of frequencies, m, to include in the regression, and establish the asymptotic normality of ^d_r. These results show that the bias of ^d_r goes to zero at a faster rate than that of the GPH estimator when the normalized spectrum at zero is sufficiently smooth, but that its variance only is increased by a multiplicative constant. We show that the bias–reduced estimator ^d_r attains the optimal rate of convergence for a class of spectral densities that includes those that are smooth of order s≥1 at zero when r≥(s−2)/2 and m is chosen appropriately. For s>2, the GPH estimator does not attain this rate. The proof uses results of Giraitis, Robinson, and Samarov (1997). We specify a data–dependent plug–in method for selecting the number of frequencies m to minimize asymptotic MSE for a given value of r. Some Monte Carlo simulation results for stationary Gaussian ARFIMA (1, d, 1) and (2, d, 0) models show that the bias–reduced estimators perform well relative to the standard log–periodogram regression estimator.     

Self‐Help Groups in the Welfare State: Treatment Program or Voluntary Action?

This article identifies two different perspectives used when studying self‐help groups: the professional treatment perspective and the voluntary action perspective. An outline of the perspectives leads to a discussion of their consequences for self‐help group research. The authors categorize about five hundred scientific publications from all over the world on the basis of the perspectives they present on self‐help groups; the results indicate that different perspectives seem to be preferred in different countries and when discussing different subjects. Finally, the authors suggest questions and concepts that the perspectives generate, and they emphasize the importance of being aware of which perspective is used in the study of self‐help groups.     

Finite mixture modeling of censored regression models

A finite mixture of Tobit models is suggested for estimation of regression models with a censored response variable. A mixture of models is not primarily adapted due to a true component structure in the population; the flexibility of the mixture is suggested as a way of avoiding non-robust parametrically specified models. The new estimator has several interesting features. One is its potential to yield valid estimates in cases with a high degree of censoring. The estimator is in a Monte Carlo simulation compared with earlier suggestions of estimators based on semi-parametric censored regression models. Simulation results are partly in favor of the proposed estimator and indicate potentials for further improvements.