A woman decides to take seriously the claim that some shampoos will give hair more body. She buys five different shampoos and uses a different one each day. Each day, she randomly chooses six coworkers and asks them to rate her hair on a 10-point scale ( 10 being high). The ratings are shown in the table. Does kind of shampoo make a difference? \begin{tabular}{lllll} \hline A & B & C & D & E \\ \hline 7 & 6 & 8 & 7 & 6 \\ 7 & 6 & 7 & 8 & 8 \\ 7 & 6 & 7 & 8 & 6 \\ 6 & 7 & 7 & 6 & 7 \\ 8 & 5 & 7 & 7 & 7 \\ 7 & 6 & 6 & 5 & 6 \\ \hline \end{tabular}
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- Null hypothesis (\(H_0\)): The kind of shampoo does not make a difference in the ratings. - Alternative hypothesis (\(H_a\)): The kind of shampoo does make a difference in the ratings. Show more…
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