If you’re happy and you know it … send a Tweet? Researchers say that our word choices in social media reveal our emotions, and now they’ve used Twitter to map the country’s happiness.

A group of researchers at the Vermont Complex Systems Center ranked words in over 10 million tweets from 2011 on a happiness scale. Tweets with words such as “laughter,” “love,” “rainbow” and “smile” rank high on that scale, whereas “terrorist,” “ugly,” “cancer,” “die” and “fatal” come in at the bottom.

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Napa ranks as the happiness city in the United States using this method, and Beaumont, Texas, as the saddest.

As for states, “Hawaii emerges as the happiest state due to an abundance of relatively happy words such as ‘beach’ and food-related terms,” the authors wrote in the study published in PLoS ONE. “Louisiana is revealed as the saddest state, with a significant factor being an abundance of profanity relative to the other states.”

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The locations ranked unhappiest tend to feature more profanity in their Tweets, but they also correspond with other happiness predictors, like rates of poverty and how prone a place is to natural disasters.

To see Twitter’s happiest and saddest cities of the day, check out @geographyofhapp, a Twitter feed created by study co-author Christopher Danforth.

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