@lautrec,
lautrec wrote:
The following is sample information. Test the hypothesis at the .05 significance level that the treatment means are equal.
Treatment 1 (9,7,11,9,12,10) Treatment 2 (13,20,14,13)
Treatment 3 (10,9,15,14,15)
a. State the null hypothesis and the alternate hypothesis.
b. What is the decision rule?
c. Compute SST, SSE, and SS total.
d. Complete an ANOVA table.
e. State your decision regarding the null hypothesis.
I'll get you started...
Assuming the data are from a completely randomized design:
a. Ho: The treatment means are equal, or u1=u2=u3
Ha: The treatment means are not all equal.
b. If your F-statistic falls in the upper 5% of the sampling distribution of F then reject Ho; otherwise do not reject Ho.
c. SSTest, SSError, and SStotal each have formula that you can use for your data. They are also known as Between Group (or Test), Within Group (or Error) and Total Sums of Squares.
d. The purpose of completing the ANOVA table is to derive F which is MeanSquare(Test)/MeanSquare(Error).
e. Once you have your F value take it to an F distribution table and find the proper row and column using the number of degrees of freedom for v1 (#groups - 1) and v2 (#groups(n-1)).