# Confidence Interval for Standard Deviation

Listed below are (in micrograms per cubic meter, or mg/m3) in the air. An organization has established an air quality standard for lead of 1.5 mg/m3. The measurements shown below were recorded at a destroyed building on different days immediately following its destruction. Assume that this sample is a simple random sample obtained from a population with a normal distribution. Use the given value to construct an 80% confidence interval estimate of the standard deviation of the amounts of lead in the air. Is there anything about this data set that suggests that the confidence interval might not be very good?

4.93 1.15 0.54 0.76 0.44 1.15

See attachment.

© BrainMass Inc. brainmass.com June 4, 2020, 12:45 am ad1c9bdddfhttps://brainmass.com/statistics/confidence-interval/confidence-interval-estimate-standard-deviation-amounts-357856

#### Solution Preview

Please see the attachments.

Answer

The confidence interval estimate is 1.257 µg/m3 < σ < 3.011 µg/m3

80% confidence interval for the population standard deviation is ...

#### Solution Summary

The solution provides step by step method for the calculation of confidence interval for standard deviation. Formula for the calculation and Interpretations of the results are also included. Interactive excel sheet is included. The user can edit the inputs and obtain the complete results for a new set of data.