Mixed mode designs are increasingly important in surveys and large longitudinal studies are progressively moving to or considering such a design. In this context our knowledge regarding the impact of mixing modes on data quality indicators in longitudinal studies is sparse. This study tries to...

The quasi-simplex model makes use of at least three repeated measures of the same variable to estimate its reliability. The model has rather strict assumptions about how various parameters in the model are related to each other. Previous studies have outlined how several of the assumptions of...

Using multiple modes to collect data is becoming a standard practice in survey agencies. While this should save costs and decrease non-response error it may have detrimental effects on measurement quality. This can happen because different modes have distinct measurement biases which, when...

We consider the effect of a wave of mixed-mode data collection (telephone and face-to-face), in an otherwise face-to-face survey, on panel attrition and the extent to which this effect is dependent on the nature of the mode-switch protocol. Findings are reported from an experiment on a survey in...

This study empirically identifies dimensions of behaviour that are distinct in terms of the extent to which people act pro-environmentally. Three dimensions are identified, relating to at-home, transport-related and purchasing behaviour. The correlation between behaviour in each dimension is...