SOLUTION: A psychologist wants to estimate the standard deviation of IQ scores. It is widely believed that IQ scores follow a normal distribution. Her random sample of 16 IQ scores has a mea
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Question 1090844: A psychologist wants to estimate the standard deviation of IQ scores. It is widely believed that IQ scores follow a normal distribution. Her random sample of 16 IQ scores has a mean of 102
and a standard deviation of 13.3. Find the 95% confidence interval for the population standard deviation based on this sample.
Carry your intermediate computations to at least three decimal places. Round your answers to at least two decimal places.
What is the lower and upper limit of the 95% confidence interval? Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website! The interval is mean +/- t(df=15, 0.97 * s/sqrt(n), where t=2.131 and n=16
102+/- 2.131*13.3/4; the interval width is 7.086
(94.91, 109.09).
