Question: The recommended acidity levels for sweet white wines (e.g., certain Rieslings, Port, Eiswein, Muscat) is .70% to .85% (www.grapestompers.com/articles/measure_acidity.htm). A vintner (winemaker) takes three random samples of Riesling from casks that are 15, 20, and 25 years old, respectively, and measures the acidity of each sample. The sample results are given in the table below.
a. We are to test whether the mean acidity levels for all casks of Riesling are the same for the three different ages. Write the null and alternative hypotheses.
b. Show the rejection and nonrejection regions on the F distribution curve for α = .025.
c. Calculate SSB, SSW, and SST.
d. What are the degrees of freedom for the numerator and the denominator?
e. Calculate the between-samples and within-samples variances.
f. What is the critical value of F for α = .025?
g. What is the calculated value of the test statistic F?
h. Write the ANOVA table for this exercise.
i. Will you reject the null hypothesis stated in part a at a significance level of 2.5%?