Flyer International Happiness Scale Interval Study

International Happiness Scale Interval Study

Survey studies in your country have involved questions about happiness, such as:

Taking all together, how happy would you say you are these days?
– Very happy
– Fairly happy
– Not too happy

We want to know what difference people in your country see between such response options. How much more happiness is meant with ‘very happy’ than with ‘fairly happy’? How unhappy is ‘not too happy’?

You can help us by a answering some questions on the internet. This will take about 10 minutes.

Please go to………..

Log on with: codeword …………

The goal of this study is explained in more detail on the back of this page.

The principal investigator is professor Ruut Veenhoven of Erasmus University Rotterdam in The Netherlands and director of the World Database of Happiness. The co-investigator in your country is ………………                             

for which this study provides a solution

Survey questions on happiness
Happiness is ones subjective appreciation of life, in other words: how much one likes ones life. Since people know how they feel about their life, researchers can measure a person’s happiness by simply asking them how happy they are. Such questions are commonly used for large-scale survey studies throughout the world. A typical question in English would be:

Taking all things together, how happy would you would you say you are these days…?
– very happy
– quite happy
– not very happy
– not at all happy

Some people might think that this method is too simplistic, but the answers to such questions appear to be meaningful. We now know in which countries people are the happiest, and can explain why in some countries people are happier than others.

Limitations to comparability of answers
Yet researchers, in different studies, use slightly different questions, and this limits our ability to compare across countries and between studies. The following problems are involved.

Distance of response options
It is typically assumed that the distances between answer options are equal and on this basis responses are given numerical values, e.g. 1 for ‘not happy at all’ and 2 for ‘not very happy’, 3 for ‘quite happy’ and 4 for ‘very happy’. Is this assumption just? Is the difference between ‘very happy’ and ‘quite happy’ really the same as the difference between ‘quite happy’ and ‘not very happy?

Wording of response options
Questions differ in the words used for response options, e.g. ‘pretty happy’ instead of ‘quite happy’. Do such subtle differences in phrasing make a difference? And if so: How much difference?

Although in international studies often the same question is used in different countries, a problem remains. Can we be sure that verbal labels have exact equivalents in other languages? Does ‘happy’ in English mean exactly the same as ‘heureux’ in French or  ‘feliz’ in Spanish or does translation introduce subtle differences?

Solution: Estimation of numerical values for verbal response options

Many of these problems can be dealt with using Thurstone’s transformation technique, in which experts assign numerical values to verbal response options. In this study we use a variation of that technique. We show you some survey questions that have been used in your country in your language. Next to each question we present a 0 to10 line-scale. We ask you to divide the scale in ranges that correspond with the response options, e.g. which part of the scale denotes ‘very happy’. We will use your ratings for re-analysis of available data, from which we will calculate weighted means on range 0 to 10.

For more detail go to:

Back to World Database of Happiness, International Happiness Scale Interval Study