You are not logged in.
Pages: 1
18 people are randomly selected with a mean score of 550 and a std. dev. of 140. Find the 95% confidence interval for the population variance and std.
can you tell me how i find point estimates for population variance and standard deviation?
Thanks in advance.
Letter, number, arts and science
of living kinds, both are the eyes.
Offline
18 people are randomly selected with a mean score of 550 and a std. dev. of 140. Find the 95% confidence interval for the population variance and std.
can you tell me how i find point estimates for population variance and standard deviation?
Thanks in advance.
Prakash,
This sounds like you can use a Chi-Square Confidence interval. We have our Sample N = 18 and our confidence percentage of 95%. Since standard deviation is 140, squaring that gets us our variance of 19600.
Go here and plug those 3 in:
Chi-Square Confidence Interval for the Variance and Standard Deviation
This will show you every single line of math for how to determine both the variance and standard deviation confidence i nterval. Press either button to see the math work. You will notice about halfway down I provide a shortcut in Microsoft Excel for how to calculate some of the values on the fly if you ever need to.
Let me know if I can provide more assistance.
Last edited by mathceleb (2008-12-17 04:38:28)
Offline
Pages: 1