Exploiting Zero-Inflated Consumption Data using Propensity Score Matching and the Infrequency of Purchase Model, with Application to Climate Change Policy

We apply propensity score matching (PSM) to the estimation of household motor fuel purchase quantities, to tackle problems caused by infrequency of purchase. The results are compared to an alternative, regression-based, imputation strategy using the infrequency of purchase model (IPM). Using data from the UK’s National Travel Survey (NTS) we observe that estimated mean obtained from the PSM imputation is closer to the estimated mean from the consumption diary, than that obtained from fitted values from the IPM. The NTS also contains an interview question on household mileage which can be used to assess the results of imputation. We find that the order statistics of the imputed distribution are more plausible for the PSM estimates than those obtained using the IPM, judging by the sample distribution of household mileage. We argue that there are some applications for which the PSM method is likely to be superior, including estimates of distributional effects of policies. On the other hand, the IPM is more suitable for analysing conditional effects and associations of consumption with covariates. We illustrate our arguments using a simple microsimulation exercise on CO2 emissions reduction policies, an area where methods for coping with zero-inflated data seem currently to be under-used

Distributional effects of climate change mitigation policies

Climate change scholars generally urge that CO2 emissions need to be cut rapidly if we are to avoid dangerous risks of climate change. However, climate change mitigation policies are widely perceived to have regressive effects — that is, putting a higher financial burden as a proportion of household income on poor than on rich households. This is one of several major barriers to the adoption of effective mitigation policies. They would also have considerable social justice implications requiring significant welfare state responses. We assess the claim that climate change policies have regressive effects by comparing different types of mitigation policies. We will argue that many of these are indeed likely to have regressive distributional implications but that there are several policy options to counteract regressive effects

Effect of a telephonic alert system (Healthy Outlook) for patients with chronic obstructive pulmonary disease: cohort study with matched controls

Background: Healthy Outlook was a telephonic alert system for patients with Chronic Obstructive Pulmonary Disease (COPD) in the United Kingdom. It used routine meteorological and communicable disease reports to identify times of increased risk to health. We tested its effect on hospital use and mortality. Methods: Enrolees with a history of hospital admissions were linked to hospital administrative data. They were compared with control patients from local general practices, matched for demographic characteristics, health conditions, previous hospital use and predictive risk scores. We compared unplanned hospital admissions, admissions for COPD, outpatient attendances, planned admissions and mortality, over 12 months following enrolment. Results: Intervention and matched control groups appeared similar at baseline (n=1,413 in each group). Over the 12 months following enrolment, Healthy Outlook enrolees experienced more COPD admissions than matched controls (adjusted rate ratio 1.26, 95% CI, 1.05 to 1.52) and more outpatient attendances (adjusted rate ratio 1.08, 95% CI 1.03 to 1.12). Enrolees also had lower mortality rates over 12 months (adjusted odds ratio 0.61, 95% CI, 0.45 to 0.84). Conclusion: Healthy Outlook did not reduce admission rates, though mortality rates were lower. Findings for hospital utilisation were unlikely to have been affected by confounding

Exploiting Zero-Inflated Consumption Data using Propensity Score Matching and the Infrequency of Purchase Model, with Application to Climate Change Policy

We apply propensity score matching (PSM) to the estimation of household motor fuel purchase quantities, to tackle problems caused by infrequency of purchase. The results are compared to an alternative, regression-based, imputation strategy using the infrequency of purchase model (IPM). Using data from the UK’s National Travel Survey (NTS) we observe that estimated mean obtained from the PSM imputation is closer to the estimated mean from the consumption diary, than that obtained from fitted values from the IPM. The NTS also contains an interview question on household mileage which can be used to assess the results of imputation. We find that the order statistics of the imputed distribution are more plausible for the PSM estimates than those obtained using the IPM, judging by the sample distribution of household mileage. We argue that there are some applications for which the PSM method is likely to be superior, including estimates of distributional effects of policies. On the other hand, the IPM is more suitable for analysing conditional effects and associations of consumption with covariates. We illustrate our arguments using a simple microsimulation exercise on CO2 emissions reduction policies, an area where methods for coping with zero-inflated data seem currently to be under-used

Focal Points Revisited: Team Reasoning, the Principle of Insufficient Reason and Cognitive Hierarchy Theory

Coordination on focal points in one shot games can often be explained by team reasoning, a departure from individualistic choice theory. However, a less exotic explanation of coordination is also available based on best-responding to uniform randomisation. We test the team reasoning explanation experimentally against this alternative, using coordination games with variable losses in the off-diagonal cells. Subjects’ responses are observed when the behaviour of their partner is determined in accordance with each theory, and under game conditions where behaviour is unconstrained. The results are more consistent with the team reasoning explanation. Increasing the difficulty of the coordination tasks produces some behaviour suggestive of response to randomisation, but this effect is not pronounced

A Consultation to Identify the Research Needs in Research Methods in the UK Social Sciences

An extensive consultation is reported with members of the UK research methods community, broadly conceived, into the perceived needs for research into research methods for social sciences. Research needs identified are the following, grouped by topic; the first four were particularly prominent in the consultation

Consultation on research needs in research methods in the UK social sciences

One of the objectives of the National Centre for Research Methods (NCRM) is to assess current national provision and national needs in research methods and training through consultation with key stakeholders. An extensive consultation on the needs for research in research methods was undertaken in 2006. This report is an update of that exercise. Four groups of people participated in this consultation via interview or questionnaire: leading researchers working on research relating to the seven key ESRC Strategic Research Challenges identified in the ESRC strategic Plan 2009-2014; participants to the 2006 consultation; Directors of NCRM and National Centre for e-Social Science (NCeSS) Nodes; and, learned societies. An open call for responses from the broader social research community was also issued. A total of 32 responses from these various sources were received. The findings of this consultation identify the perceived needs for research in research methods of a relatively small number of social and economic researchers. These may not be representative of the views of all social scientists but that was not our intention. Rather, they represent the considered views of, primarily, senior social scientists about key areas of future research need. The areas identified overlap to a considerable extent with the findings of the 2006 consultation. Ten key topics of methodological research need were identified with each one comprising a number of issues. These are listed below. The small-scale and purposive nature of this consultation means it is not possible to attribute any priority to the needs identified on the basis of the responses received. 1. Mixed methods and interdisciplinarity Development of models to enable the integration of qualitative and quantitative research in single studies that go beyond traditional mixed methods models; methods to enable the integration of data collected via innovative methods with other forms of qualitative or quantitative data; collaboration between social science disciplines and social science and other disciplines to enable methodological development to address key research questions. 2. Naturally occurring digital data and new digital technologies Methods to capture and analyse new forms of online and digital data; methods to enable the use of media tools to collect data; methods to exploit the use of global positioning systems and radio frequency identification and other mobile devices in research. 3. Longitudinal methods The development of enhanced qualitative longitudinal methods to track change and continuity over time; development of methods to determine causality using longitudinal data; development of methods for dynamic programming and path dependence in discrete choice models; development of methods for combining event history analysis with multi-level modelling and the analysis of data with spatial structure. 4. Data linkage Methodological research to develop understanding of the properties of linked data; research in spatial/temporal trends, bias adjustment and imputation of missing covariates and outcomes; methodological research to improve the availability of data linkage tools to ensure access and data security; methodological development to enable the linking of bio-medical and socio-economic data; research on the integration of transactional data and other forms of digital data 5. Policy evaluation Development of methods to analyse the effect of multiple interventions on outcomes and the importance of social contexts; further work on microsimulation models; further development of systematic review methods. 6. Innovations in qualitative research Development of ethnographic approaches; critical evaluation of mobile methods; methodological development of sensory methods; development of methods and technology to enable the archiving and sharing of multi-media qualitative data. 7. Survey methods Research on sampling and analysis in internet and mixed-mode surveys; research on the use of paradata; methods for minimising non-response bias. 8. Comparative research The development of methods for cross-cultural comparisons and for the incorporation of qualitative and quantitative data in comparative analysis; development of comparative historical research methods; standardisation and harmonisation of measures for comparative microdata. 9. The ethics, politics and practice of research Research on the ethical issues arising from online and digital methods and data use; methods for engaging non-academic users; methods for measuring the impact of research on policy and practice. 10. Holistic methods Development of methods within a complexity theory framework; development of holistic and interdisciplinary research methods to explore issues such as environmental change. While the 2006 Research Needs Consultation was used as a template for organising the emerging topics from this consultation, there are some important similarities and differences. The continuing need for research within the areas of mixed methods, interdisciplinarity, policy evaluation, comparative research, data linkage, longitudinal research, survey methods, and innovative qualitative methods are evident. Three new areas of methodological research need were also identified: naturally occurring digital data and technological developments; the ethics, politics and practice of research; and, holistic methods. This consultation has explored the methodological research needs perceived by, among others, those addressing substantive research topics identified as current ‘strategic research challenges’ by the ESRC. The need for methodological research to enable researchers to address these key research challenges as well as issues of research impact is highlighted by this consultation