I would take it with a sizeable grain of salt but that's what a recent Gallup poll claims:
Among other questions, the survey asks respondents whether they had recently experienced emotions such as enjoyment, physical pain, worry, stress or anger, and whether they had recently smiled or laughed a lot.
This does fit the sterotype for orderly, well-managed, authoritarian Singapore -- a country that has gone to some pretty bizarre lengths in an effort to get citizens to have more sex.
Not surprisingly, Singaporeans don't seem to worked up about this. The Guardian rounds up some bemused tweets including "Singapore ranked most emotionless country in the world – not sure how to feel about that" and "That [poll] is a lie. I use many emoticons to express how satisfied I am." Going only on stereotypes, it's little more surprising to see the country that brought us Tchaikovsky, Tolstoy, and vodka at number four.
Who are the world's most emotional people? It's those soap opera-loving Filipinos followed by basically the whole Western Hemisphere and a couple of Gulf states:
Make of this what you will.