A researcher is interested in studying the effects of using a dress code in middle schools on students' feelings of safety. Three schools are identified as having roughly the same size, racial composition, income levels, and disciplinary problems. The researcher randomly assigns a type of dress code to each school and implements it in the beginning of the school year. In the first school (A), no formal dress code is required. In the second school (B), a limited dress code is used with restrictions on the colors and styles of clothing. In the third school (C), school uniforms are required. Six months later, five students at each school are randomly selected and given a survey on fear of crime at school. The higher the score, the safer the student feels. Test the hypothesis that feelings of safety do not differ depending on school dress codes. (
α
=
0.05
; follow the 12 steps to conduct an ANOVA).

Fear-of-crime Scores

School A School B School C
3 2 4
3 2 4
3 2 3
4 1 4
4 3 3
1) State the
H
0
and
H
1
, expressed in words and mathematical terms.

2) Find the mean for each sample.

3) Find the sum of scores, sum of squared scores, number of subjects, and mean for all groups combined.

A