The measurement effect between modes in MM surveys (mixed-mode surveys) may impede the applicability of survey estimates and the comparability of survey estimates between socio-demographic segments within a MM survey, the comparability between different editions of periodic MM surveys and the comparability with similar surveys in other countries.
Estimating the extent of the measurement effect between modes in MM surveys is a key step for evaluating the severity of the problem in individual MM survey, designing strategies to minimize the measurement effect between modes and for factoring them in the final survey estimates.
The aim of this master’s thesis is to estimate the measurement effects between modes in the MM consumer confidence survey conducted by the Slovenian Statistics Office, in which a combination of web and telephone modes is used to collect data. In this setting, two hypotheses were examined. The first one relates to the presence of a measurement effect between modes and the second one to its direction. Given the nature of data available, we applied the backdoor method and the comparative sample method.
Results show that both hypotheses can be confirmed by both methods. As anticipated, we also found differences between the two methods owing directly to their specific characteristics. In this context, the backdoor method shows weaker measurement effect between modes but is potentially more advantageous due to its practicality and low costs, especially if improved.