A hedonometer or hedonimeter is a device used to gauge happiness or pleasure. Conceived of at least as early as 1880,[1] the term was used in 1881 by the economist Francis Ysidro Edgeworth to describe "an ideally perfect instrument, a psychophysical machine, continually registering the height of pleasure experienced by an individual."[2]
More recently, it has been used to refer to a tool developed by Peter Dodds and Chris Danforth to gauge the valence of various corpora, including historical State of the Union addresses, song lyrics, and online tweets and blogs.[3][4][5] It is operated out of the University of Vermont (UVM), and has been in use since 2008.[6] A version of the tool is available at hedonometer.org, which they call a sort of "Dow Jones Index of Happiness",[7] and hope will be used by government officials in conjunction with other metrics as a gauge of the population's well-being.[8]
Computer scientists trained the hedonometer to recognize the emotion behind data as tweets with sentiment analysis techniques. Danforth preferred a lexicon approach, that measures the weight of a word, due to the energy required for neural nets.[9]
As of 2020, the hedonometer at UVM scrapes about 50 million tweets each day. Using sentiment analysis, the hedonometer takes the emotional temperature of the words published by users of various platforms.[6]