Question

Alcohol in wine. The alcohol content of wine depends on the grape variety, the way in which the wine is produced from the grapes, the weather, and other influences. The percent of alcohol in wine produced from the same grape variety in the same year by 18 winemakers in the same region of Italy had a mean alcohol content of 13.15 and standard deviation of 1.53. Is the mean alcohol content significantly different at the α = 0.05 level from 12%?

1. (a) What is the research hypothesis?

2. (b) Give the null and alternative statistical hypotheses.

3. (c) Compute t

4. (d) The p-value of computed t is:

5. (e) Decision:rejectorfailtorejectH0

6. (f) Conclusion: What does this mean with regard to the research hypothesis?

Answer 1

A. Research Hypothesis: There is no significant affect of grape variety, weather and other influences on the alcohol content in wine

B.

Null Hypothesis, Ho: The mean alcohol content in wine is 12 i.e.

Alternative Hypothesis, H1: The mean alcohol content in wine is significantly different from 12 i.e.

C.

Test-Statistics: Under Ho,

So,   

D.

Using t-tables,

E. Decision: Since p-value = 0.000657 < alpha = 0.05 so we reject Ho at 5% level of significance

F. Conclusion: We conclude that the mean alcohol content in wine is significantly different from 12%