When: The Scientific Secrets of Perfect Timing

by Daniel H. Pink

Positive affect—language revealing that tweeters felt active, engaged, and hopeful—generally rose in the morning, plummeted in the afternoon, and climbed back up again in the early evening. Whether a tweeter was North American or Asian, Muslim or atheist, black or white or brown, didn’t matter. “The temporal affective pattern is similarly shaped across disparate cultures and geographic locations,”

The main point – that our mood changes in a predictable way over the course of a day – is interesting. But so is the methodology. One of the promises of Big Data is that it allows us to see patterns like this – which are invisible to the eye but reveal important patterns lurking beneath the surface.