SOLUTION: Please help me with this problem. A researcher conducts an experiment comparing three treatment conditions. The data consist of n =20 scores for each treatment condition. a.

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Question 1088675: Please help me with this problem.
A researcher conducts an experiment comparing three treatment conditions. The data consist of n =20 scores for each treatment condition.
a. If the researcher used an independent-measures design, then how many individuals were needed for the study and what are the df-values for the F-ratio? Explain in detail and show all formulas with symbols (and plug in numbers), steps, processes and calculations for all parts of the answers.
b. If the researcher used a repeated measures-design, then how many individuals were needed for the study and what are the df-values for the F-ratio? Explain in detail and show all formulas with symbols (and plug in numbers), steps, processes and calculations for all parts of the answers.

Answer by reviewermath(1029) (Show Source):
You can put this solution on YOUR website!
a)The independent-measures design F-ratio has df = ,
df(between treatments) = k-1 = 3 � 1 = 2
df(Total) = N-1 = 60 � 1 = 59
df(error) = df(Total) - df(between treatments) = 59 - 2 = 57
Hence, the independent-measures design F-ratio has df = 2, 57
60 individuals were needed for the study
b) The repeated-measures F-ratio has df = ,
df(between subjects) = n-1 = 20 � 1 = 19
df(within treatments) = Σ df inside each treatment = 19 + 19 + 19 = 57
df(between treatments) = k-1 = 3 � 1 = 2
df(error) = df(within treatments) - df(between subjects) = 57 - 19 = 38
Hence, the repeated-measures F-ratio has df = 2, 38
20 individuals were needed for the study (same subjects for each treatment)