What kind of evidence is this?
6
In 2007, Belgian researchers surveyed 1,656 teenagers about their use of mobile
phones after lights-out, and found those who used a phone less than once per
week were more than twice as likely to be 'very tired" a year later as those who never
did. (from "The End of Night" by Rebecca Boyle)
Hypothetical
12
Analogy
Study
15
Expert opinion