<abstract xmlns="http://www.w3.org/1999/xhtml"><p> The confounding of selection and measurement effects between different modes is a disadvantage of mixed-mode surveys. Solutions to this problem have been suggested in several studies. Most use adjusting covariates to control selection effects. Unfortunately, these covariates must meet strong assumptions, which are generally ignored. This article discusses these assumptions in greater detail and also provides an alternative model for solving the problem. This alternative uses adjusting covariates, explaining measurement effects instead of selection effects. The application of both models is illustrated by using data from a survey on opinions about surveys, which yields mode effects in line with expectations for the latter model, and mode effects contrary to expectations for the former model. However, the validity of these results depends entirely on the (ad hoc) covariates chosen. Research into better covariates might thus be a topic for future studies.</p></abstract>

The confounding of selection and measurement effects between different modes is a disadvantage of mixed-mode surveys. Solutions to this problem have been suggested in several studies. Most use adjusting covariates to control selection effects. Unfortunately, these covariates must meet strong assumptions, which are generally ignored. This article discusses these assumptions in greater detail and also provides an alternative model for solving the problem. This alternative uses adjusting covariates, explaining measurement effects instead of selection effects. The application of both models is illustrated by using data from a survey on opinions about surveys, which yields mode effects in line with expectations for the latter model, and mode effects contrary to expectations for the former model. However, the validity of these results depends entirely on the (ad hoc) covariates chosen. Research into better covariates might thus be a topic for future studies.

Evaluating Mode Effects in Mixed-Mode Survey Data Using Covariate Adjustment Models

Institute for Social & Economic Research, University of Essex, Wivenhoe Park, Colchester, Essex CO4 3SQ, United Kingdom

Centre for Sociological Research, KU Leuven, Parkstraat 45, Leuven 3000, Belgium

I-BioStat, KU Leuven, Leuven, and Universiteit Hasselt, Diepenbeek, Belgium

Journal of Official Statistics

The confounding of selection and measurement effects between different modes is a disadvantage of mixed-mode surveys. Solutions to this problem have been...

Evaluating Mode Effects in Mixed-Mode Survey Data Using Covariate Adjustment Models

Published Online: Feb 14, 2014

Page range: 1 - 21

DOI: https://doi.org/10.2478/jos-2014-0001

Keywords
Selection effects, measurement effects, back-door model, front-door model, causal inference, opinion about surveys

This content is open access.

Evaluating Mode Effects in Mixed-Mode Survey Data Using Covariate Adjustment Models

Published Online: Feb 14, 2014

Page range: 1 - 21

DOI: https://doi.org/10.2478/jos-2014-0001

KeywordsSelection effects, measurement effects, back-door model, front-door model, causal inference, opinion about surveys

This content is open access.

Keywords
Selection effects, measurement effects, back-door model, front-door model, causal inference, opinion about surveys