Imagine We Were Interested in the Effect of Supporters Singing

Multiple Choice

Imagine we were interested in the effect of supporters singing on the number of goals scored by soccer teams.We took 10 groups of supporters of 10 different soccer teams and asked them to attend three home games,one at which they were instructed to sing in support of their team compare?

A) Positive singing vs.no singing
B) No singing vs.negative singing
C) Negative singing vs.positive singing
D) We cannot tell which groups the levels represent from this output.