Statistics Help
Question: A confidence interval estimate is determined from the weights of an SRS (simple random sample) of n students. Which of the following will result in a SMALLER confidence interval width?
I. A smaller sample size
II. A smaller sample standard deviation
III. A smaller confidence level
a) I only
b) II only
c) III only
d) II and III
e) I and III Edit
Answer: e) I and III
Because , margin of error=sigma/sqrt(n)*z_c
if n small and z_c large the margin of error large , so interval (x bar -me, x bar +me) will be large. Edit
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