A little while back, we told you about the Science of Happiness experiment run by British psychologist Richard Wiseman. The goal was to get a large sample of people to sign up for the experiment and then figure out what makes people happy. More than 26,000 people took part, and preliminary results are in.
The findings? It looks like the best way to boost your mood is to think about something good that happened to you the day before.
As Wiseman writes on his blog:

The result show that spending just a few moments thinking about one thing that went well yesterday is a surprisingly effectively way of boosting happiness. Compared to those in the control group, this procedure resulted in a 15 percent boost in reported happiness.

Other mood-improving techniques proved effective as well. Participants who spent time thinking of something they were grateful for improved their mood 9 percent more than a control group, while those who spent time deliberately smiling improved their happiness 8 percent more than those who didn’t.
Here’s the really interesting thing, though: Members of a group that was asked to perform small acts of kindness each day during the week also improved their mood—but 9 percent less than the control group did, a result that Wiseman says baffled him.
Both before and after the experiments, Wiseman surveyed 2,000 people in Britain to see how cheerful they felt. He wanted to see whether the national mood would change during the time of his mood-boosting study. In other words, whether happiness is contagious.
He found:

Around 50 percent of the population described themselves as cheerful, and about 30 percent of people as uncheerful (20 percent were undecided). Interestingly, the results revealed a 7 percent increase in cheerfulness after the experiment. Obviously, it is impossible to say if this rise was due to the happiness project as it might be caused by many different factors, including world events or changes in the weather.