Interviewer effects in quantitative surveys using a door-to-door approach

Interviewers are a principal source of error in quantitative surveys. While surveys are often self-administered (e.g. in online surveys), it is often required to administer these face-to- face. This is the case, for example, in census surveys in low-income areas where there is little internet penetration, like that of the quality-of-life surveys presently being conducted in multiple countries through a residential door-to-door approach (Carr et al., 2018). In such situations, the social interaction between the interviewer conducting the survey and the interviewee is likely to introduce bias into the survey data collected. Interviewer effects (IE) can influence both item non-response and answer quality, i.e., participants not providing the true answer (Harling, et al., 2019). In an attempt to gain more representative data, this study conducted an exploratory analysis on the possible antecedents and consequences of interviewer effects using the Living Wage survey presently being conducted in South Africa, as the study context. To this end, I examine the systematic biasing effects associated with deploying the same group interviewers (n = 10), of the same ethnicity, age, and of equal gender distribution across five sampling areas in Cape Town in a quasi-experimental design (n = 282). This study highlighted that each interviewer is associated with a unique set of systematic bias that varies dependent on the survey item type. Sensitive items requiring respondents to disclose personal information were the most prone to bias, followed by interviewer-referencing and attitudinal items sequentially. Furthermore, this study found that gender differences in the interview had a marginal influence on the attitudes respondents are willing to share. I hope to contribute to an understanding and critical consideration of the antecedents and consequences of deploying human interviewers for collecting quantitative surveys, especially in a context where ethnic, gender and political differences are loaded in social interactions and are likely to contribute to respondents obscuring their responses

The link approach to measuring consumer surplus in transport networks

Should one calculate user benefits from changes in door-to-door journeys or from changes in the use of separate links of the network? The second approach is often discarded for its perceived inability to deal with new links and the OD-matrix approach is favoured. Differences arise when the set of used routes changes. A consumer model containing a general static transportation network with explicit non-negativity constraints serves as a basis for welfare measures expressed in shadow prices. The approximation error when applying the link approach need not be too severe. A rehabilitation of the link approach may be in order.

Sensor-based dynamic trajectory planning for smooth door passing of intelligent wheelchairs

Traditionally, it is difficult for elderly and disabled people to control a wheelchair passing a narrow doorway manually. This paper presents a dynamic trajectory planning algorithm for wheelchairs to pass a door smoothly and automatically. It is a sensor-based approach in which two laser rangefinders are deployed in the wheelchair for real-time door detection. To generate smooth trajectories that enable a wheelchair to pass a door perpendicularly, Bézier curve based trajectories are calculated repeatedly during the whole course of door passing. The proposed approach is tested on a real wheelchair and the experimental results are presented to show the good performance and effectiveness of our proposed automatic door passing strategy

The disappearance of the "revolving door" patient in Scottish general practice: successful policies

<b>Background</b> We describe the health of "revolving door" patients in general practice in Scotland, estimate changes in their number over the timescale of the study, and explore reasons for changes, particularly related to NHS and government policy.<p></p> <b>Methods</b> A mixed methods predominantly qualitative study, using a grounded theory approach, set in Scottish general practice. Semi-structured interviews were conducted with professional key informants, 6 Practitioner Services staff who administer the GP registration system and 6 GPs with managerial or clinical experience of working with "revolving door" patients. Descriptive statistical analysis and qualitative analysis of patient removal episodes linked with routine hospital admissions, outpatient appointments, drug misuse treatment episodes and deaths were carried out with cohorts of "revolving door" patients identified from 1999 to 2005 in Scotland.<p></p> <b>Results</b> A "revolving door" patient is removed 4 or more times from GP lists in 7 years. Patients had complex health issues including substance misuse, psychiatric and physical health problems and were at high risk of dying. There was a dramatic reduction in the number of "revolving door" patients during the course of the study.<p></p> <b>Conclusions</b> "Revolving door" patients in general practice had significant health problems. Their numbers have reduced dramatically since 2004 and this probably resulted from improved drug treatment services, pressure from professional bodies to reduce patient removals and the positive ethical regulatory and financial climate of the 2004 GMS GP contract. This is a positive development for the NHS

A mass reduction effort of the electric and hybrid vehicle

Weight reduction, cost competitiveness, and elimination of the intrusion beam resulted from the redesign and fabrication using composite materials of the door outer panel and intrusion beam from a Chevrolet Impala. The basis of the redesign involved replacing these two steel parts with a single compression molding using the unique approach of simultaneously curing a sheet molding compound outside panel with a continuous glass fiber intrusion strap. A weight reduction of nearly 11 pounds per door was achieved. Additional weight savings are possible by taking advantage of the elimination of the intrusion beam to design thinner door structures. The parts consolidation approach allows the composite structure to be cost competitive with the original steel design for both the lower production car models and for the near to midterm production vehicles using current state of the art composite production techniques. The design, prototype fabrication, costing, material, properties and compression molding production requirements are discussed

Doorway passing of an intelligent wheelchair by dynamically generating Bézier curve trajectory

Door passing is the basic capability of an intelligent wheelchair. This paper presents a novel strategy to address the door passing issue by dynamically generating the Bézier curve based trajectory. It consists of door finding, optimization based trajectory generation and tracking control, which are executed repeatedly to increase the ability of passing the door and improve the performance. Whenever the door is detected, the optimization method produces a new smooth reference trajectory in real time for the wheelchair to follow. The proposed approach is tested in reality to verify its feasibility and efficiency, and the experimental results show its good performance in terms of the accuracy of finding the door and passing the doorway. © 2012 IEEE

Toward an Understanding of the Economics of Charity: Evidence from a Field Experiment

This study develops theory and uses a door-to-door fundraising field experiment to explore the economics of charity. We approached nearly 5000 households, randomly divided into four experimental treatments, to shed light on key issues on the demand side of charitable fundraising. Empirical results are in line with our theory: in gross terms, our lottery treatments raised considerably more money than our voluntary contributions treatments. Interestingly, we find that a one standard deviation increase in female solicitor physical attractiveness is similar to that of the lottery incentive¡ªthe magnitude of the estimated difference in gifts is roughly equivalent to the treatment effect of moving from our theoretically most attractive approach (lotteries) to our least attractive approach (voluntary contributions).

Exploration of a Potential Desirability of Outcome Ranking Endpoint for Complicated Intra-Abdominal Infections Using 9 Registrational Trials for Antibacterial Drugs

BACKGROUND: Desirability of outcome ranking (DOOR) is a novel approach to clinical trial design that incorporates safety and efficacy assessments into an ordinal ranking system to evaluate overall outcomes of clinical trial participants. Here, we derived and applied a disease-specific DOOR endpoint to registrational trials for complicated intra-abdominal infection (cIAI). METHODS: Initially, we applied an a priori DOOR prototype to electronic patient-level data from 9 phase 3 noninferiority trials for cIAI submitted to the US Food and Drug Administration between 2005 and 2019. We derived a cIAI-specific DOOR endpoint based on clinically meaningful events that trial participants experienced. Next, we applied the cIAI-specific DOOR endpoint to the same datasets and, for each trial, estimated the probability that a participant assigned to the study treatment would have a more desirable DOOR or component outcome than if assigned to the comparator. RESULTS: Three key findings informed the cIAI-specific DOOR endpoint: (1) a significant proportion of participants underwent additional surgical procedures related to their baseline infection; (2) infectious complications of cIAI were diverse; and (3) participants with worse outcomes experienced more infectious complications, more serious adverse events, and underwent more procedures. DOOR distributions between treatment arms were similar in all trials. DOOR probability estimates ranged from 47.4% to 50.3% and were not significantly different. Component analyses depicted risk-benefit assessments of study treatment versus comparator. CONCLUSIONS: We designed and evaluated a potential DOOR endpoint for cIAI trials to further characterize overall clinical experiences of participants. Similar data-driven approaches can be utilized to create other infectious disease-specific DOOR endpoints