Notice: the WebSM website has not been updated since the beginning of 2018.

Web Survey Bibliography

Title The numeric values of rating scales: A comparison of their impact in mail surveys and telephone interviews
Author Schwarz, N., Hippler, H. J.
Year 1994
Access date 13.05.2013

PDF (540 kb)


This article presents a study which compared the impact of numeric values of rating scales in mail surveys and telephone interviews. The specific numeric values presented as part of a rating scale may change the meaning of the scale's verbal endpoints, essentially resulting in responses to different questions. The authors provide a conceptual replication of this finding in a different content domain and compared the relative strength of the impact of numeric values under telephone and mail survey conditions. The data are drawn from a larger experimental survey conducted with a systematic random sample of 412 adults (18 years or older), selected from the telephone directories for Mannheim and Heidelberg, Germany, in November and December 1991. The findings of the study replicate the phenomenon observed by Norbert Schwarz et al. in a different content domain and across two administration modes. Respondents use formal features of the questionnaire to determine the exact meaning of a question. Hence, combining a verbal label with a negative numeric value suggests a more negative interpretation of the verbal scale anchor and results in more positive responses along the scale. The findings indicate that the numeric values do not need to be presented in a visual format to receive sufficient attention.

Access/Direct link

Homepage (Abstract)

Year of publication1995
Bibliographic typeJournal article