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• Ruut Veenhoven (2009)
  International scale interval study: Improving the comparability of responses to survey questions about happiness
  in: Valerie Moller & Dennis Huschka (Eds.) ‘Quality of life and the millennium challenge: Advances in quality-of-life studies, theory and research’, Social Indicators Research Series vol. 35, Springer, e-ISBN 978-1-4020-8569-7, pp. 45-58
  
  
• Wim Kalmijn (2010)
  Quantification of happiness inequality
  PhD dissertation, Erasmus University Rotterdam, The Netherlands, 2-12-2010
  
  
• Kalmijn, W.M., Arends, L.R. & Veenhoven, R. (2011)
  Happiness Scale Interval Study: Methodological considerations
  Social Indicators Research 102(3) 497-515, DOI 10.1007/s11205-010-9688-2
  
  
• DeJonge, T. Arends, L. & Veenhoven, R. (2014)
  Homogenizing responses to different survey questions on the same topic: Proposal of a scale homogenization method using a reference distribution
  Social Indicators Research,117: 275–300 DOI 10.1007s11205-013-0335-6.
  
  
• DeJonge, T. (2015)
  Different survey questions on the same topic: How to make responses comparable?
  Doctoral dissertation Erasmus University Rotterdam
  
  
• DeJonge, T. Arends, L., Kalwijn, W., Moonen, L., VanBeuningen, J. & Veenhoven, R.(2016)
  Pooling time series based on slightly different questions about the same topic: Forty years of survey research on happiness and life-satisfaction in the Netherlands
  Social Indicators Research, 126 (2) 863-891, DOI: 10.1007/s11205-015-0898-5 Open Access
  
  
• DeJonge, T. Arends, L, Kalmijn, W . & Veenhoven, R. (2016)
  Conversion of verbal response scales: Robustness across demographic categories
  Social Indicators Research, 126(1), 331-358, DOI: 10.1007/s11205-015-0879-6 Open Access
  
  
• DeJonge, T. (2017)
  Methods to Increase the Comparability in Cross-National Surveys, Highlight on the Scale Interval Method and the Reference Distribution Method
  In Brule, G. & Maggino, F. (2017) Metrics of Subjective well-being: Limits and Improvements, pp 237-262. DOI – 10.1007/978-3-319-61810-4_12

• DeJonge, T., Kalmijn, W . & Veenhoven, R. (2017) Diversity in survey questions on the same topic: Techniques for improving comparability
  Social Indicators Research Book Series. Volume 68, ISBN: 978-3-319-53260-8 (Print) 978-3-319-53261-5 (Online)

• De Jonge, T., Kamasaka, A. & Veenhoven, R. (2019)
  Have the Japanese become happier over the last 50 years? Healing broken time-series data EHERO working paper 2019-3

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