Gretchen Rubin's The Happiness Project and the Cheerfulness Facet
Gretchen Rubin spent a year testing whether happiness actually responds to deliberate effort, and The Happiness Project is the field report. Her headline finding, in a Barking Up The Wrong Tree interview, is that "it really is possible for most people to make themselves happier, just within the confines of the ordinary day." It takes no life overhaul, she found, just small daily moves. In the Big Five, your baseline level of that sunny feeling is one facet.
The baseline is the Cheerfulness facet
Cheerfulness (E6), under Extraversion, is your default supply of positive emotion, the tendency to feel joy and good spirits without much prompting. A high scorer runs warm and up by nature; a low scorer sits more neutral and has to work harder for the same lift. This is a set point, and it is fairly stable, which is exactly why Rubin's framing is careful: she is careful not to promise a rebuilt temperament, only a way to get the most out of the E6 you already have.
Her most useful trick is the one that sounds too simple to work. Rubin's rule is to act the way she wants to feel, and, as she put it in a LifeHack interview, "This 'fake it 'till you feel it' strategy isn't new, but I've been astounded by how effective it is." Force the smile and the mood often follows, a real behavioral-feedback effect. It also helps to separate two things people run together: low Cheerfulness (E6) is not the same as high Depression (N3). One is a quiet baseline, the other an active downward pull, and Rubin's habits are aimed at the first.
We cover the facet on its own in Cheerfulness (E6). The honest read on The Happiness Project is that it will not move your set point much, and it never claims to; what it does is wring the available happiness out of an ordinary Tuesday, which for most people is more than they are currently collecting.
Read the book: The Happiness Project by Gretchen Rubin.
See Where You Fall
Where do you actually fall? The 30-facet OCEAN personality test takes about 15 minutes and scores all five domains and the facets underneath them. Take the test
Research Citations
Rubin, G. (2009). The happiness project. Harper.
Lucas, R. E., Diener, E., Grob, A., Suh, E. M., & Shao, L. (2000). Cross-cultural evidence for the fundamental features of extraversion. Journal of Personality and Social Psychology, 79(3), 452-468.
Johnson, J. A. (2014). Measuring thirty facets of the Five Factor Model with a 120-item public domain inventory: Development of the IPIP-NEO-120. Journal of Research in Personality, 51, 78-89.
Costa, P. T., & McCrae, R. R. (1992). Revised NEO Personality Inventory (NEO-PI-R) professional manual. Psychological Assessment Resources.