In his book The 4-Hour Workweek, author and entrepreneur Timothy Ferriss argues that "Happiness can be bought with a bottle of wine and has become ambiguous through overuse." In addition to suffering overuse in popular culture, happiness is ambiguous for at least two reasons: Happiness has many definitions, from the profound to the mundane, and the development of any happiness index will necessarily suffer from the inclusion of either too few or too many sources of happiness, depending on perspectives. In addition, happiness is a relative phenomenon: The same absolute score on a dimension of happiness (for example, monetary resources) can make one person feel happy and another person feel miserable, depending on comparisons with other people's standing on the same dimension. For example, Carol Graham, in Happiness Around the World: The Paradox of Happy Peasants and Miserable Millionaires, explains why poor Hondurans are happier than poor Chileans, even though the former live in a poorer country than that of the latter. "Because average country income levels do not matter to happiness, but relative distances from the average do, the poor Honduran is happier because their distance from the mean income is smaller." In other words, poor Hondurans feel better than poor Chileans because poor Hondurans' incomes are closer to middle-class incomes in their country than poor Chileans' incomes are—a relative happiness effect.

Interestingly, the relativity of happiness is also a within-person phenomenon. When asked how happy a person feels today, the person could anchor his or her judgment relative to the experiences of other people, much as Carol Graham suggests, or the person could anchor judgments relative to the person's own experiences over time. For example, the person may feel "very happy" today in comparison with a week ago when the person had the flu. Or the person may hope to feel happier in the future if some event occurs, such as finding a better job. Thus, the measurement of happiness over time requires both an understanding of how people feel in a social context and how they feel over time. Interestingly, research on construal level theory, first developed by Nira Liberman and Yaacov Trope, shows that a distant time horizon results in abstract construal, whereas a near time horizon results in concrete construal. For example, a person may agree to do a job due to start three months from today, because the person is thinking about the work abstractly (he or she will do the job and receive pay). When the time comes near to do the job, the person may regret taking the job, because now he or she is thinking about the work concretely, in terms of all the incomplete tasks up until now that will interfere with the new work, for example. In terms of happiness, people may overestimate how happy they will feel in the future and exaggerate how happy they felt at some point in the distant past, because distant experiences tend to be devoid of concrete information.

Ferriss's comment that "happiness can be bought with a bottle of wine" suggests that some sources of happiness are more superficial than others. In addition to citing wine, Ferriss could have mentioned boxes of chocolate, sugary drinks, inauthentic praise, and any other relatively inexpensive intervention that raises levels of momentary cheerfulness. Along those lines, companies have begun to use happiness consistently to promote short-term boosts in mood or cheerfulness. Nestlé's claims that "Happiness is as easy as Nesquik." Clinique is marketing Clinique Happy perfume spray, and Boss Orange claims to be "the fragrance of happiness." Dunkin Donuts encourages consumers to open a "Box of Happiness," whereas Nivea Body Lotion promotes "Happy Sensations."

A happiness index that relates consistently to a firm's strategic branding and long-term customer-loyalty efforts requires identification of enduring sources of happiness or sources beyond those that result merely in momentary cheerfulness. Coca-Cola's long-standing happiness branding incorporates deeper social-emotional definitions of happiness, including generosity and time spent with family and friends, even though the core product design is clearly to raise happiness only momentarily through learned taste preferences for sugar and dopaminergic pathways in the brain (example of a viral Coca-Cola video: https://www.youtube.com/watch?v=lqT_dPApj9U).

Similarly, Yahoo!'s "Purple Acts of Kindness" campaign encouraged users to engage in small acts of prosocial behavior, a branded community campaign that likely generated long-term brand value for Yahoo!, as the analysis in future reports in this series will show.