Bags of a certain brand of tortilla chips claim to have a ne

Bags of a certain brand of tortilla chips claim to have a net weight of 14 ounces. Net weights actually vary slightly from bag to bag and are normally distributed with mean . A representative of a consumer advocate group wishes to see if there is any evidence that the mean net weight is less than advertised and so intends to test the hypotheses H0: = 14, Ha: < 14. To do this, he selects 16 bags of this brand at random and determines the net weight of each. He finds the sample mean to be r2-1.png?_&d2lSessionVal=CQFJW51QOMKYwD5 = 13.88 and the sample standard deviation to be s = 0.24. Reference: Ref 7-2 Suppose we were not sure if the distribution of net weights was normal. In which of the following circumstances would we not be safe using a t procedure in this problem? Question options: A. The mean and median of the data are nearly equal. B. A histogram of the data shows moderate skewness. C. A stemplot of the data has a large outlier. D. The sample standard deviation is large.

Solution

It would be

OPTION C: A stemplot of the data has a large outlier. [ANSWER]

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This could affect the distribution of our sample mean adversely, because we only have n = 16 sample size here. As much as possible, we do not want outliers at this small sample size.