Whither RDS? An investigation of respondent driven sampling as a method of recruiting mainstream marijuana users.

Background: An important challenge in conducting social research of specific relevance to harm reduction programs is locating hidden populations of consumers of substances like cannabis who typically report few adverse or unwanted consequences of their use. Much of the deviant, pathologized perception of drug users is historically derived from, and empirically supported, by a research emphasis on gaining ready access to users in drug treatment or in prison populations with higher incidence of problems of dependence and misuse. Because they are less visible, responsible recreational users of illicit drugs have been more difficult to study. Methods: This article investigates Respondent Driven Sampling (RDS) as a method of recruiting experienced marijuana users representative of users in the general population. Based on sampling conducted in a multi-city study (Halifax, Montreal, Toronto, and Vancouver), and compared to samples gathered using other research methods, we assess the strengths and weaknesses of RDS recruitment as a means of gaining access to illicit substance users who experience few harmful consequences of their use. Demographic characteristics of the sample in Toronto are compared with those of users in a recent household survey and a pilot study of Toronto where the latter utilized nonrandom self-selection of respondents. Results: A modified approach to RDS was necessary to attain the target sample size in all four cities (i.e., 40 'users' from each site). The final sample in Toronto was largely similar, however, to marijuana users in a random household survey that was carried out in the same city. Whereas well-educated, married, whites and females in the survey were all somewhat overrepresented, the two samples, overall, were more alike than different with respect to economic status and employment. Furthermore, comparison with a self-selected sample suggests that (even modified) RDS recruitment is a cost-effective way of gathering respondents who are more representative of users in the general population than nonrandom methods of recruitment ordinarily produce. Conclusions: Research on marijuana use, and other forms of drug use hidden in the general population of adults, is important for informing and extending harm reduction beyond its current emphasis on 'at-risk' populations. Expanding harm reduction in a normalizing context, through innovative research on users often overlooked, further challenges assumptions about reducing harm through prohibition of drug use and urges consideration of alternative policies such as decriminalization and legal regulation.

Medidas de intervención para promoción de conductas saludables y prevención de riesgos laborales relacionados con accidentalidad y enfermedad laboral en trabajadores de minas de Carbón

Colombia en su legislación normatiza el sector de la minería de carbón, sin embargo se considera que las estrategias no han sido suficientes para la identificación, prevención y control de la accidentalidad y enfermedad laboral. Durante el año 2013 el índice de fatalidad fue de 1,59. Estadísticas del año 2004 evidencian que las neumoconiosis fueron las mayores causas de invalidez de origen profesional. Objetivo: Categorizar actividades de intervención en promoción y prevención de accidentalidad y enfermedad laboral en trabajadores de la minería de carbón. Metodología: Se realizó una revisión de literatura sobre minería de carbón y salud la cual fue obtenida de las bases de datos PUBMED, Sciendirect, VHL, SINAB por literatura publicada sin límites de año, en idioma inglés, español o portugués. Para la búsqueda se utilizaron términos en lenguaje controlado (términos MESH), revisión por pares de títulos y resúmenes. Las publicaciones fueron seleccionadas para revisión de texto completo bajo criterios de inclusión y exclusión. Los códigos contemplados para esta revisión fueron: a) país donde la intervención se llevó a cabo, b) salud ocupacional, c) prevención de accidentalidad, d) programas de promoción, e) tecnologías, f) resultados obtenidos. Resultados: Del total de 2500 artículos seleccionados por los autores principales se realizó la revisión de los primeros 300 artículos, 32 hacen referencia al tema de salud ocupacional y minería de carbón, 10 contienen intervenciones consideradas de relevancia para esta revisión bibliográfica. Se presentan intervenciones estadísticamente significativas (p<0.05) y que han demostrado ser de impacto positivo en la minería de carbón en promoción y prevención de accidentalidad y enfermedad ocupacional. Conclusiones: Se identificaron las siguientes cuatro tipos de intervención: 1) las de carácter educativo que hacen referencia a las capacitaciones participativas, el entrenamiento por medio de “degraded image”, la realización de gestión de autocontrol y retroalimentación para el uso de elementos de protección personal (EPP), la aplicación del Modelo de Proceso Paralelo Extendido; 2) intervenciones preventivas como la medición de alcoholimetría antes del turno, la presencia de personal de enfermería en minas de carbón y el reconocimiento de los predictores de la enfermedad para optimizar la prevención primaria; 3)intervenciones de vigilancia como la promovida en la metodología Estadísticas Europeas de Accidentes de Trabajo (EEAT) para la investigación de los accidentes de trabajo, la aplicación de las recomendaciones de la Organización Mundial de la Salud (OMS) para la detección de la neumoconiosis y 4) De carácter tecnológico consistente en la intervención de tareas a partir de los resultados de la aplicación del software desarrollado por el Instituto Nacional para la Seguridad y Salud Ocupacional (NIOSH). Estas intervenciones han demostrado ser eficaces en la promoción y prevención de accidentalidad y enfermedad ocupacional por lo cual se recomienda su aplicación en Colombia posterior al análisis de costo-efectividad.

The missing pillar: the creativity theory of knowledge spillover entrepreneurship

Knowledge spillover theory of entrepreneurship and the prevailing theory of economic growth treat opportunities as endogenous and generally focus on opportunity recognition by entrepreneurs. New knowledge created endogenously results in knowledge spillovers enabling inventors and entrepreneurs to commercialize it. This article discusses that knowledge spillover entrepreneurship depends not only on ordinary human capital, but more importantly also on creativity embodied in creative individuals and diverse urban environments that attract creative classes. This might result in self-selection of creative individuals into entrepreneurship or enable entrepreneurs to recognize creativity and commercialize it. This creativity theory of knowledge spillover entrepreneurship is tested utilizing data on European cities.

Firms in international trade: importers’ and exporters’ heterogeneity in Italian manufacturing industry

Combining data on structural characteristics and economic performance for a large sample of Italian firms with data on exporting and importing activity, we uncover evidence supporting recent theories on firm heterogeneity and international trade, together with some new facts. In particular, we find that importing is associated with substantial firm heterogeneity. First, we document that trade is more concentrated than employment and sales, and show that importing is even more concentrated than exporting both within sectors and along the sector- and country-extensive margins. Second, while supporting the fact that firms involved in both are the best performers, we also find that firms involved only in importing activities perform better than those involved only in exporting. Our evidence suggests there is a strong self-selection effect in the case of importers and the performance premia of internationalised firms correlate relatively more with the degree of geographical and sectoral diversification of imports.

The Role of Collateral in Entrepreneurial Finance

Previous research has suggested collateral has the role of sorting entrepreneurs either by observed risk or by private information. In order to test these roles, this paper develops a model which incorporates a signalling process (sorting by observed risk) into the design of an incentivecompatible menu of loan contracts which works as a self-selection mechanism (sorting by private information). It then tests this Sorting by Signalling and Self-Selection Model, using the 1998 US Survey of Small Business Finances. It reports for the first time that: high type entrepreneurs are more likely to pledge collateral and pay a lower interest rate; and entrepreneurs who transfer good signals enjoy better contracts than those transferring bad signals. These findings suggest that the Sorting by Signalling and Self-Selection Model sheds more light on entrepreneurial debt finance than either the sorting-by-observed-risk or the sorting-by-private information paradigms on their own.

Recovering the counterfactual wage distribution with selective return migration

This paper recovers the distribution of wages for Mexican-born workers living in the U.S. if no return migration of Mexican-born workers occurred. Because migrants self-select in the decision to return, the overarching problem addressed by this study is the use of an estimator that also accounts for selection on unobservables. I find that Mexican returnees are middle- to high-wage earners at all levels of educational attainment. Taking into account self-selection in return migration, wages would be approximately 7.7% higher at the median and 4.5% higher at the mean. Owing to positive self-selection, the immigrant-native wage gap would, therefore, partially close if there was no return migration.

Part-time employment within the Swedish retail business : – A study of part-time employment from a management perspective

Research question: How has the presence of PT employees affected the role of managers in the Swedish food retail business? Research purpose: The purpose of this paper was to describe the change that accompanies part-time employment from a management perspective, and particularly, describe how the presence of part-time employment has influenced the role of the manager within the Swedish food retail business. Conceptual framework: The main focused in this chapter is directed towards the role of managers. The basis of the conceptual framework consist of the model developed by Mintzberg including the ten managerial roles and Quinn's eight leadership roles and how the presence of PT employments might affect these roles. Methodology: In this paper, the authors adopted a qualitative design and used narrative inquiry as a research strategy in order to gain a deep understanding of the context. Semi- structured interviews have been collected through a self-selection sampling and the total number of participants was ten. Conclusions: Based on the findings of this paper the presence of PT employees have not influenced and changed the role of managers. The changes that have influenced and caused the change of the role of the managers constitutes of the increased workload, the delegations of tasks and responsibilities, changed positions, the change of the organisational structure of the individual store, and the increased workforce.

Neighborhood walkability and the walking behavior of Australian adults

Background
The physical attributes of residential neighborhoods, particularly the connectedness of streets and the proximity of destinations, can influence walking behaviors. To provide the evidence for public health advocacy on activity-friendly environments, large-scale studies in different countries are needed. Associations of neighborhood physical environments with adults’ walking for transport and walking for recreation must be better understood.

Method
Walking for transport and walking for recreation were assessed with a validated survey among 2650 adults recruited from neighborhoods in an Australian city between July 2003 and June 2004, with neighborhoods selected to have either high or low walkability, based on objective measures of connectedness and proximity derived from geographic information systems (GIS) databases. The study design was stratified by area-level socioeconomic status, while analyses controlled for participant age, gender, individual-level socioeconomic status, and reasons for neighborhood self-selection.

Results
A strong independent positive association was found between weekly frequency of walking for transport and the objectively derived neighborhood walkability index. Preference for walkable neighborhoods moderated the relationship of walkability with weekly minutes, but not the frequency of walking for transport—walkability was related to higher frequency of transport walking, irrespective of neighborhood self-selection. There were no significant associations between environmental factors and walking for recreation.

Conclusions
Associations of neighborhood walkability attributes with walking for transport were confirmed in Australia. They accounted for a modest but statistically significant proportion of the total variation of the relevant walking behavior. The physical environment attributes that make up the walkability index are potentially important candidate factors for future environmental and policy initiatives designed to increase physical activity.

Is growth inhibited in non-elite competitive female gymnasts?

PURPOSE
We asked: 1) is statural growth inhibited in non-elite competitive female gymnasts?; and 2) if growth is reduced, is the effect similar for legs and spine?

METHODS
Height(Ht), sitting height(StHt) and leg length(LL) were measured in gymnasts and controls at baseline and every 12 mths for 2 yrs. Pubertal status was assessed by Tanner stage. Gymnasts were from USGF levels 4–10 and trained 7.5 to 22.5 hrs/wk. Age-adjusted Z-scores were determined for gymnasts on the anthropometric measures and based on linear regression analyses of data for 45 controls.

RESULTS
At baseline, pre-(N=40), peri-(N=16) and post-pubertal(N=11) gymnasts were shorter than controls(-0.9 to -1.3 SD, p < 0.01). In pre- and peri-pubertal gymnasts, this was due to a reduction in StHt (-0.8 to -1.3 SD) and LL (-0.8 to -1.1 SD)(p < 0.01). In post-pubertal gymnasts, StHt (-0.8 SD) was reduced (p < 0.05). No differences were observed in z-score deficits between pubertal groups, nor were there any differences in StHt and LL deficits. During 12 mths follow-up in 39 gymnasts, deficits in Ht z-scores were reduced further in pre-pubertal gymnasts (-0.2 SD, p < 0.001) due to a greater increase in the deficit in LL (-0.3 SD, p < 0.001). While the magnitude of z-score deficits for peri-pubertal gymnasts remained unchanged, Ht z-scores improved in post-pubertal gymnasts(+0.2SD, p < 0.05) due primarily to an increase in StHt (+0.4 SD, p < 0.01). Similar results were found in 16 gymnasts followed for 2 yrs.

CONCLUSION
Although small size may relate to self-selection for gymnastics, some non-elite female gymnasts may experience attenuated growth during early puberty due mainly to reduced leg growth. The increased growth observed in post-pubertal gymnasts is consistent with catch-up growth associated with delayed maturation.

Investigating sample bias in student evaluations of teaching

Student evaluations of teaching have increased in importance to universities in Australia over recent years due to changes in government policy. There has been significant debate in the literature as to the validity and usefulness of such evaluations and as to whether students who respond to the evaluations are indeed representative of the student population. A potential invalidating issue is self selection in the evaluation process. In this paper, we consider student evaluations of a large first year business statistics subject that had 1073 eligible students enrolled across four campuses at the time of the evaluation. The study is based on the 373 students (34.8%) who responded to the survey, and their final results. The evaluations were open for a period of six weeks leading up to and just after the final exam. The study looks in detail at the student population identifying such attributes as gender; home campus; course of study; domestic/international; Commonwealth Supported Place/full fee paying, etc. and then mapping these results to those of the students who responded to the survey.

From rural beginnings to statewide roll-out : evaluation of facilitator training for a group-based diabetes prevention program

Objective: To evaluate the approach used to train facilitators for a large-scale group-based diabetes prevention program developed from a rural implementation research project.

Participants: Orientation day was attended by 224 health professionals; 188 submitted the self-learning task; 175 achieved the satisfactory standard for the self-learning task and attended the workshop; 156 completed the pre- and post-training questionnaires.

Main outcome measures: Two pre- and post-training scales were developed to assess knowledge and confidence in group-based diabetes prevention program facilitation. Principal component analysis found four factors for measuring training effectiveness: knowledge of diabetes prevention, knowledge of group facilitation, confidence to facilitate a group to improve health literacy and confidence in diabetes prevention program facilitation. Self-learning task scores, training discontinuation rates and satisfaction scores were also assessed.

Results: There was significant improvement in all four knowledge and confidence factors from pre- to post-training (P < 0.001). The self-learning task mean test score was 88.7/100 (SD = 7.7), and mean assignment score was 72.8/100 (SD = 16.1). Satisfaction with training scores were positive and 'previous training' interacted with 'change in knowledge of diabetes prevention program facilitation' but not with change in 'confidence to facilitate.'

Conclusions: The training program was effective when analysed by change in facilitator knowledge and confidence and the positive mean satisfaction score. Learning task scores suggest tasks were manageable and the requirement contributed to facilitator self-selection. Improvement in confidence scores in facilitating a group-based diabetes prevention program, irrespective of previous training and experience, show that program-specific skill development activities are necessary in curriculum design.

Does the change of accounting regulation on employee share options give rise to greater scope for earnings management?

Purpose – The purpose of this paper is to address the concern about the impact of accounting regulatory change pertaining to employee share options (ESOs) on earnings management. Following Australia’s adoption of International Financial Reporting Standards (IFRS) in 2005, companies are required to recognise the fair value of ESOs as expenses. Due to inherent imprecision in the estimate of ESO’s fair value, the regulatory change from disclosure to recognition was widely claimed to potentially give rise to an alternative mechanism to manage earnings. This study provides empirical evidence on whether the regulatory change leads to earnings management problems.

Design/methodology/approach – This study uses the regulatory change in accounting for ESOs to provide a direct test of earnings management between disclosed versus recognised regimes for the same sample of firms. The sample consists of Australian firms from S&P/ASX300 for the period from 2003 to 2006.

Findings – The results show that, although the accounting regulatory change from disclosure to recognition may provide an alternative earnings management vehicle, there is no evidence of this occurring. There could be several reasons for this finding. First, the statistical tests lack power. Second, there are stricter audit tests on recognised amounts than on disclosed amounts. Third, given the concern of excessive pay and the close scrutiny of compensation, managers may have already understated ESO values in the disclosure regime. Finally, managers have limited time and resources and the effort involved in the adoption of IFRS in 2005 could have restricted the time available to manage earnings via the ESO reporting channel.

Originality/value – This study adds to the limited research on whether a change in accounting regulation for employee share options from disclosure to recognition gives rise to greater scope for earnings management. One reason for the lack of empirical evidence in the research is due to the problem of designing a test. Bernard and Schipper suggest that within-firm studies have limitations for comparing the effects of recognition versus disclosure when the change is driven by an estimate becoming more reliable. A cross-sectional study is also problematic due to self-selection bias if firms can choose between disclosure versus recognition. This study circumvents potential design problems raised by Bernard and Schipper by setting a test using regulatory change which allows the test to be compared directly using the same company.

A new urban planning code's impact on walking: The residential environments project

Objectives. We examined whether people moving into a housing development designed according to a state government livable neighborhoods subdivision code engage in more walking than do people who move to other types of developments.

Methods. In a natural experiment of 1813 people building homes in 73 new housing developments in Perth, Western Australia, we surveyed participants before and then 12 and 36 months after moving. We measured self-reported walking using the Neighborhood Physical Activity Questionnaire and collected perceptions of the environment and self-selection factors. We calculated objective measures of the built environment using a Geographic Information System.

Results. After relocation, participants in livable versus conventional developments had greater street connectivity, residential density, land use mix, and access to destinations and more positive perceptions of their neighborhood (all P < .05). However, there were no significant differences in walking over time by type of development (P > .05).

Conclusions. Implementation of the Livable Neighborhoods Guidelines produced more supportive environments; however, the level of intervention was insufficient to encourage more walking. Evaluations of new urban planning policies need to incorporate longer term follow-up to allow time for new neighborhoods to develop.

A stakeholder approach to corporate social responsibility, reputation and business performance

Purpose - This paper aims to investigate business managers' assessment of stakeholders' influence on corporate social responsibility (CSR) initiatives. The key stakeholders included "employees" and "unions" as internal and "public", the "media" and the "government" as external stakeholders. The purpose was to estimate the influence of stakeholders that managers perceive as important. Moreover, the study sought to identify association between the CSR construct and corporate reputation and in turn whether this influences business performance. Design/methodology/approach - This study uses a mail survey with a random sampling of senior managers sourced from Dun & Bradstreet's Australian business database, focusing on large organizations (i.e. minimum $10 million p.a. reported sales and minimum 100 employees) as the selection criteria. A conceptual model was developed and tested using structural equation modeling. Findings - The results identified that "employees" and the "public" are perceived to be the influential stakeholder groups in CSR decision-making. There was evidence of a positive relationship between the CSR construct and reputation, which in turn influenced market share, but not profitability. Research limitations/implications - This study examined a cross-section of organizations using Dun & Bradstreet's database of Australian businesses and may not fully represent the Australian business mix. The effective response rate of 7.2 per cent appears to be low, even though it is comparable with other research in the CSR area. There may have been some self-selection by the respondents, although there were no statistically significant differences identified in the corporate characteristics of those invited to participate and those responding with usable questionnaires. Practical implications - Managers can adopt a stakeholder-influenced CSR strategy to generate strong corporate reputation to improve business performance. It is important to ensure that the interests of "employees" and "public" stakeholders are addressed within organizational strategy. Respondents were less concerned about government stakeholders and thus government involvement in organizational CSR may need to be revisited. Social implications - The major concern that emerges from these findings is the absence of the perceived importance of regulatory stakeholders on firms' CSR activities. Regulatory controls of CSR messages could reduce or eliminate inaccurate and misleading information to the public. Originality/value - The analysis explains the perceived relative influence of stakeholders on CSR decisions. It also provides an understanding of the link between organizational CSR reputation and organization's performance.

Segmentation in the brazilian labor market

This paper measures the degree of segmentation in the brazilian labor market. Controlling for observable and unobservable characteristics, workers earn more in the formal sector, which supports the segmentation hypothesis. We break down the degree of segmentation by socio-economic attributes to identify the groups where this phenomenon is more prevalent. We investigate the robustness of our findings to the inclusion of self-employed individuals, and apply a two-stage panel probit model using the self-selection correction strategy to investigate a potential weakness of the fixed-effects estimator