In: Statistics and Probability
Use the given information to find the number of degrees of freedom, the critical values chi Subscript Upper L Superscript 2 and chi Subscript Upper R Superscript 2, and the confidence interval estimate of sigma. It is reasonable to assume that a simple random sample has been selected from a population with a normal distribution. Nicotine in menthol cigarettes 90% confidence; nequals23, sequals0.25 mg.
We have given here,
Sample standard deviation=0.25
Sample size =23
Degree of freedom =n-1= 22
Level of significance given =1-0.90=0.1
Chi square critical value for lower tail=12.338
Chi square critical value for upper tail=33.924