> Simple science: you need a control group. While controlled experiments are the ideal for hypothesis testing, as someone who does stats for a living it's wort

> Simple science: you need a control group. While controlled experiments are the ideal for hypothesis testing, as someone who does stats for a living it's worth point out observational studies do exist. Entire fields, such as anthropology, depend entirely on observational statistics. The field has also come a tremendously long way in recent years with lots of very useful tools coming out of the Bayesian community (applying proper priors, multi-level modeling, inference on more complex models) and the causal inference community. McElreath's Statistical Rethinking is a great text that deals mostly with what I would consider the current state of the art in observational techniques. Highly recommended if isn't already on your bookshelf.