Bags of a certain brand of tortilla chips claim to have a net weight of 14 oz.Net weights slightly vary from bag to bag.Assume net weights are Normally distributed.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: $\mu$ = 14 versus H_a: $\mu$

Question

Bags of a certain brand of tortilla chips claim to have a net weight of 14 oz.Net weights slightly vary from bag to bag.Assume net weights are Normally distributed.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: $\mu$ = 14 versus H_a: $\mu$ < 14.To do this,he selects 16 bags of tortilla chips of this brand at random and determines the net weight of each.He finds a sample mean of 13.88 oz with a standard deviation of s = 0.24 oz.Suppose we were not sure if the distribution of net weights were Normal.In which of the following circumstances would the t procedure not be robust in this problem?

Quizplus · Accepted Answer

The t procedure assumes that the data come from a Normal distribution. However, it is robust to departures from Normality if the sample size is large enough. Outliers can have a significant impact on the sample mean and standard deviation, leading to inaccurate results. Therefore, if there is a large outlier in the data, the t procedure may not be robust in this problem. Choices A, B, and D do not affect the robustness of the t procedure.

Bags of a Certain Brand of Tortilla Chips Claim to Have