Exposure to Lead
A simple random sample of 22 full IQ scores for the group with medium exposure to lead was taken. The sample standard deviation of this sample is 14.3. Construct a 95% confidence interval estimate for the population standard deviation.
Requirements:
a) Simple random sample
b) Check normality
given data are:-
sample size (n ) = 22
sample sd (s) = 14.3
the chi square critical value table be:-
critical value | excel function | |
=CHISQ.INV.RT(0.025,21) | ||
=CHISQ.INV.RT(0.975,21) |
the 95% confidence interval for the population standard deviation be:-
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Exposure to Lead A simple random sample of 22 full IQ scores for the group with...
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