for their helpful feedback and comments. The usual caveat applies, perhaps more strongly than in most cases. The views expressed herein are those of the authors and do not necessarily reflect the views of the National Bureau of Economic Research. NBER working papers are circulated for discussion and comment purposes. They have not been peerreviewed or been subject to the review by the NBER Board of Directors that accompanies official NBER publications.

, Sciences Po and Stanford for helpful comments and suggestions. The usual caveat applies. The views expressed herein are those of the authors and do not necessarily reflect the views of the National Bureau of Economic Research. NBER working papers are circulated for discussion and comment purposes. They have not been peerreviewed or been subject to the review by the NBER Board of Directors that accompanies official NBER publications.

We show that, without strong auxiliary assumptions, it is impossible to rank groups by average happiness using survey data with a few potential responses. The categories represent intervals along some continuous distribution. The implied CDFs of these distributions will (almost) always cross when estimated using large samples. Therefore some monotonic transformation of the utility function will reverse the ranking. We provide several examples and a formal proof. Whether Moving-toOpportunity increases happiness, men have become happier relative to women, and an Easterlin paradox exists depends on whether happiness is distributed normally or log-normally. We discuss restrictions that may permit such comparisons.

In recent years, the gut microbiome has become a focal point of interest with growing recognition that a well-balanced gut microbiota composition is highly relevant to an individual’s health status and well-being. Its profile can be modulated by a number of dietary factors, although few publications have focused on the effects of what we drink. The present review performed a systematic review of trials and mechanistic studies examining the effects of tea consumption, its associated compounds and their effects on the gut microbiome. Registered articles were searched up to 10th September 2019, in the PubMed and Cochrane library databases along with references of original articles. Human trials were graded using the Jadad scale to assess quality. Altogether 24 publications were included in the main review—six were human trials and 18 mechanistic studies. Of these, the largest body of evidence related to green tea with up to 1000 mL daily (4–5 cups) reported to increase proportions of Bifidobacterium. Mechanistic studies also show promise suggesting that black, oolong, Pu-erh and Fuzhuan teas (microbially fermented ‘dark tea’) can modulate microbial diversity and the ratio of Firmicutes to Bacteroidetes. These findings appear to support the hypothesis that tea ingestion could favourably regulate the profile of the gut microbiome and help to offset dysbiosis triggered by obesity or high-fat diets. Further well-designed human trials are now required to build on provisional findings.

We estimate whether students update their college application portfolios in response to large, unanticipated information shocks generated by the release of SAT scores -a primary component of admissions decisions. Exploiting new population data on the timing of college selection and a policy that induces students to choose colleges prior to taking exam, we find that the release of scores causes students to update their portfolios in terms of selectivity, tuition, and sector. However, the magnitude of updating is too modest to significantly reduce unexplained variation across students, suggesting that non-academic factors may be the dominant determinants of college choice.