Levy, Chung and Slace $(2011)$ proposed that cultural representations could impact functional health. They predicted salient holidays, as a cultural representation would influence birth timing. They collected data about number of births on Halloween and Valentines days and recorded $4\%$ decrease and $6\%$ increase in births, respectively.

Levy, Chung and Slace's prediction on influence of salient holidays on birth timing is an example of which of the following?