Research in statistical education — planning of an international survey

As announced in the November 2000 issue of MathStats&OR [1], one of the projects supported by the Maths, Stats & OR Network funds is an international survey of research into pedagogic issues in statistics and OR. I am taking the lead on this and report here on the progress that has been made during the first year. A paper giving some background to the project and describing initial thinking on how it might be implemented was presented at the 53rd session of the International Statistical Institute in Seoul, Korea, in August 2001 in a session on The future of statistics education research [2]. It sounded easy. I considered that I was something of an expert on surveys having lectured on the topic for many years and having helped students and others who were doing surveys, particularly with the design of their questionnaires. Surely all I had to do was to draft a few questions, send them electronically to colleagues in statistical education who would be only to happy to respond, and summarise their responses? I should have learnt from my experience of advising all those students who thought that doing a survey was easy and to whom I had to explain that their ideas were too ambitious. There are several inter-related stages in survey research and it is important to think about these before rushing into the collection of data. In the case of the survey in question, this planning stage revealed several challenges. Surveys are usually done for a purpose so even before planning how to do them, it is advisable to think about the final product and the dissemination of results. This is the route I followed.

Sole agency vs multi-agency: An investigation of agency practice across England and Wales

Purpose: The purpose of this paper is to investigate the impact of different agency practice on agency fees, business efficiency, and housing market liquidity. Design/methodology/approach: The paper studies the effect of sole and multiple agency practices on estate agent efficiency, housing market liquidity, and commission fee levels. The analysis uses the survey data from 2000 to 2006 to investigate the different agency practices across England and Wales and their effect on estate agency business efficiency, housing market liquidity, selling price, and fee levels. Findings: The empirical analysis confirms that agency practice has a locality bias, that is, some regions are more likely to adopt sole agency practice than other regions. The estate agents with a sole agency practice charge a lower agency fee, help clients to achieve better selling price and are more efficient; whereas multiple agency practice facilitates liquidity in the housing market, but experiences higher fall-through rate. Research limitations/implications: The research focuses on estate agent rather than consumers due to the limitation of the data based on a research project concerning transaction costs designed prior to this analysis. Originality/value: There is little other research that investigates the residential estate agency practice and its impact on housing market in the past three decades in England and Wales. The findings are a useful guide for practitioners to better understand the issues associated with different agency practices and should enhance business efficiency and performance.

The trade unions membership dynamics and union members’ trajectories

This text presents an analysis of aggregated membership’s dynamics for Spanish trade unions, using ECVT data, as well as union memberships’ trajectories, or members’ decisions about joining the organization, permanency and responsibilities, and subsequent attrition. For the analysis of trajectories we make use of information of the records of actual memberships and the record of quitting of CCOO, and of a survey-questionnaire to a sample of leavers of the same union. This study allows us to confirm a linkage between the decision and motivations to become union member, to participate in union activities, the time of permanency, and the motives to quit the organization. We also identify five types of union members’ trajectories, indicating that, far from views that assert a monolithic structure, unions are complex organizations.

Recruitment bias and clinical characterstics of participants with severe cerebral palsy in a cross-sectional survey

Aim.  This article is a report of recruitment bias in a sample of 5–25-year-old patients with severe cerebral palsy.

Background.  The way in which study participants are recruited into research can be a source of bias.

Method.  A cross-sectional survey of 5–25-year-old patients with severe cerebral palsy using standardized questionnaires with parents/carers was undertaken in 2007/2008. A case register was used as the sampling frame, and 260 families were approached: 178/260 (68%) responded and 82/260 families never replied (non-respondents). Among responders: 127/178 (71%) opted in to the study, but only 123/127 were assessed, and 82/178 were opted out (or refused). Multivariable logistic regression giving odds ratios was used to study the association between participant characteristics and study outcomes (responders vs. non-responders; opting in vs. opting out; assessed vs. eligible, but not assessed).

Results.  Responders (compared with non-responders) were significantly more likely to have a family member with cerebral palsy who was male and resident in more affluent areas. Families who opted in (compared with those opting out and refusing) were more likely to have a family member with cerebral palsy and intellectual impairment and to reside in certain geographical areas. Families who were actually assessed (compared with all eligible, but not assessed) were more likely to have a family member with cerebral palsy and intellectual impairment.

Conclusion.  Several sources of bias were identified during recruitment for this study. This has implications for the interpretation and conclusions of surveys of people with disabilities and complex needs.

Classical novae from the POINT-AGAPE microlensing survey of M31 - II. Rate and statistical characteristics of the nova population

The POINT-AGAPE (Pixel-lensing Observations with the Isaac Newton Telescope-Andromeda Galaxy Amplified Pixels Experiment) survey is an optical search for gravitational microlensing events towards the Andromeda galaxy (M31). As well as microlensing, the survey is sensitive to many different classes of variable stars and transients. In our first paper of this series, we reported the detection of 20 classical novae (CNe) observed in Sloan r' and i' passbands.

Survey of challenges and best practice strategies for participant recruitment to research projects in northern ireland

Participant recruitment is understood to be one of the most difficult aspects of the research process. Researchers are now devoting increasing amounts of time and resources to understand how participants decide to take part in research and what researchers can do to make their work appeal to potential participants. The purpose of the study is to assess the problems experienced by researchers in Northern Ireland when recruiting human participants into trials and studies and to gain insight into how researchers handle and overcome these issues. The main research question being addressed by this research is to develop an understanding of the problems experienced by staff when recruiting human participants to research projects. Methods used to increase study recruitment were also examined. The participants in this research are investigators and other associated staff on research studies based in Northern Ireland. Potential participants were identified through contacts with research active organizations such as the academic researchers in Queen’s University Belfast and research physicians and clinical trialists employed by the Belfast Health and Social Care Trust. Each organization forwarded on the survey request via email or newsletters. Researchers willing to take part accessed the questionnaire through the Survey Monkey website. This study utilised a cross-sectional questionnaire design.

Estudio logístico en la empresa COMERFRUTAS de Colombia S.A.S para la exportación de pulpa de limón al mercado holandés

El presente documento ofrece una guía logística y análisis financiero para las pequeñas y medianas empresas (PyMES) de Colombia que deseen exportar pulpa de limón al mercado Europeo. Para el desarrollo de este trabajo se ha tomado el caso de la micro empresa COMERFRUTAS de Colombia S.A.S. (productora de pulpa de limón) y se ha realizado un estudio de competitividad de puertos, agentes de carga tanto terrestre como marítimos para dar las bases necesarias de exportación a las PyMES colombianas en un marco legal establecido.