WASHINGTON -- Twitter confirms it: People tend to wake up in a good mood and are happiest on weekends.
The fast-paced forum is offering scientists a peek at real-time, presumably little-filtered human behavior and thoughts. Cornell University researchers turned to the microblog to study mood and found a pretty consistent pattern.
The researchers analyzed English-language tweets from 2.4 million people in 84 countries, more than 500 million of the brief, conversation-like exchanges sent over two years. A computer program searched for words indicating positive mood -- happy, enthusiastic, brilliant -- or negative mood -- sad, anxious, fear.
What they found: Unless you're a night owl, a positive attitude peaks early in the morning and again near midnight, but starts to dip midmorning before rising again in the evening.
Aha, you might think, going to work and hassles like traffic explain that. After all, there was more positive tweeting on the weekend, even though the morning peak of happy tweets occurred two hours later, probably because people slept late.
Not quite. Work-related stress may play some role but it can't explain why that same midday dip occurs on the weekend, too, said lead researcher Scott Golder, a Cornell graduate student.
Instead, the pattern probably is due to the effects of sleep and our 24-hour biological clock, the circadian rhythms that signal when it's time to sleep and to wake, Golder and Cornell sociologist Michael Macy reported. Their study appears in today's edition of the journal Science.
In tweets in the United Arab Emirates, where Friday and Saturday are considered the weekend, the researchers found the same patterns, daily and weekend, even though the workday tends to begin earlier there than in the West, and the same weekend pattern.