Curbing street gang gun violence. Refer to the Journal of Quantitative Criminology (Mar. 2014) study of a program designed to curb street gang gun violence, Exercise 2.18

(p. 69).

After implementation of Boston’s Operation Ceasefire program, the researchers examined 80 shootings by members of a particular Boston street gang over the next five years.

Of these, only 18 involved shootings of non-gang members.

Use a 99% confidence interval to estimate the true proportion of shootings by members of this Boston street gang that involved non-gang members. Interpret the result.