Part 1: Comparing responses to different survey questions on the same topic -- Problems and conventional solutions -- chap. 1 Diversity in survey items and the comparability problem -- Part 2: Innovation 1: The happiness scale interval study -- chap. 2 The happiness scale interval study -- chap. 3 Use of happiness scale interval studies in this book -- chap. 4 Equivalence of rating scales using different keywords -- chap. 5 ‘Very Happy’ is not always equally happy -- chap. 6 A change in response scale comes with another interpretation of the labels: the japanese case (pm) -- Part 3: Innovation 2: The continuum approach -- chap. 7 The continuum approach -- Part 4 Innovation 3: The reference distribution method -- chap. 8 The reference distribution method -- chap. 9 Stability of the boundaries between response options for different countries -- chap. 10 Analyses of differences in trends among the happy few and the unhappy few -- chap. 11 Combining and pooling time series on life satisfaction in Japan and The Netherlands -- chap. 12 Directions for further research -- Appendices.This book describes why conventional methods fall short to solve the comparability problem and introduces three successive innovations to overcome these shortcomings. Comparability of results from different surveys using different items for the same topic is greatly hampered by the differences in response scales used. This reduces our accumulation of knowledge and has challenged researchers in the field of survey research for long to develop appropriate methods to transform ratings on different scales to attain comparable results and to correct for effects of changes in measurements and other influencing factors. The three innovations described in this volume are applied to data on happiness and life satisfaction, show better comparability of the survey results concerning the perceptions and opinions of people over time and across nations and at an increased opportunity for meta-analysis on these results. .