The relative impact of interviewer effects and sample design effects on survey precision

One of the principal sources of error in data collected from structured face-to-face interviews is the interviewer. The other major component of imprecision in survey estimates is sampling variance. It is rare, however, to find studies in which the complex sampling variance and the complex interviewer variance are both computed. This paper compares the relative impact of interviewer effects and sample design effects on survey precision by making use of an interpenetrated primary sampling unit–interviewer experiment which was designed by the authors for implementation in the second wave of the British Household Panel Study as part of its scientific programme. It also illustrates the use of a multilevel (hierarchical) approach in which the interviewer and sample design effects are estimated simultaneously while being incorporated in a substantive model of interest.     

A multilevel exploration of the role of interviewers in survey non-response

This paper illustrates the use of multilevel statistical modelling of cross-classified data to explore interviewers' influence on survey non-response. The results suggest that the variability in whole household refusal and non-contact rates is due more to the influence of interviewers than to the influence of areas. The results from separate logistic regression models are compared with the results from multinomial models using a polytomous dependent variable (refusals, non-contacts and responses). Using the cross-classified multilevel approach allows us to estimate correlations between refusals and non-contacts, suggesting that interviewers who are good at reducing whole household refusals are also good at reducing whole household non-contacts.     

An Integrated Approach to Managing Change

Complex systems often involve a huge number of variables whose interdependence must be taken into account. This makes the adoption of an integrated approach essential for the proper management of a wide range of aspects related to human life, from social matters to the environment. In particular, this paper takes into consideration three different experiences in which the use of an integrated approach represented the most effective response for managing the evolving realities we took into consideration. We focused on the issue of land management, with particular attention to the problem of monoculture in Brazil. Then we analyzed the attempted cooperation between the States of the Aral Sea area for efficient water management of the basin and, finally, we dealt with the matter of energy efficiency and how the production of home integrated systems could lead to a better rationalization of energy consumption in the near future.      

A covariance structure model test of antecedents of adolescent alcohol misuse and a prevention effort

As part of an alcohol misuse prevention evaluation, questionnaires were administered to 4,157 junior high school students to determine levels of alcohol misuse, exposure to peer use and misuse of alcohol, susceptibility to peer pressure, internal health locus of control, and self-esteem. A conceptual model of the antecedents of adolescent alcohol misuse and the effectiveness of a prevention effort was tested using covariance structure modeling techniques. The factor loadings for the model were all moderate to high, indicating that the observed variables served well as measurement instruments for the latent variables. The hypothesized structural relationships among the latent variables of alcohol misuse, exposure to peer use and misuse of alcohol, susceptibility to peer pressure, internal health locus of control, and self-esteem were supported by the data. The full model explained 45 percent of the variance in alcohol misuse in the analysis based on the total sample. The direct effect of the intervention on alcohol misuse was small but significant in the hypothesized direction. The direct effects of the intervention on susceptibility to peer pressure and internal health locus of control were not significant. The model was tested separately for groups of students who had high versus low scores on susceptibility to peer pressure in order to test the interaction between susceptibility to peer pressure and exposure to peer use and misuse of alcohol. The percentage of variance accounted for in alcohol misuse did not increase upon testing the model separately for students who had high versus low scores on susceptibility to peer pressure. Observed differences in the significance of the parameter estimates between the high and low susceptibility to peer pressure groups suggest that different approaches to the design and evaluation of substance abuse prevention programs may be necessary for different subgroups of students.