A group of nutritionists is hoping to prove that a new soy bean compound has more protein per gram than roast beef, which has a mean protein content of 20. A random sample of 5 batches of the soy compound have been tested, with the following results: Protein content: 15, 22, 17, 19, 23
What assumption(s) do we have to make in order to carry out a legitimate statistical test of the nutritionists’ claim?
1. We must assume that the observations come from a normally distributed population AND that the mean content of the sample follows the normal distribution
2. The variance of the population is known
3. The mean protein content of the 5 batches follows a normal distribution
4. The observations are from a normally distributed population
We must assume that the observations come from a normally distributed population AND that the mean content of the sample follows the normal distribution AND that the population variance is known.