2013 - STA1000S Handin tutorial week 9 answers

5 a b upper bound lower bound c the

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: a) , ( ) ( ) b) Upper bound – Lower bound c) ( ), √ √ , √ The professor can the 68.26% confident that the estimated mean is within 3 units from the population mean. d) Increase the sample size 1 days, ants, ̅ a) Hypotheses: Level of significance: 6. days, days against days ̅ Test statistic: √ √ Critical region: Reject is | | Therefore, reject the null hypothesis, and conclude that the lifetimes of the ants are significantly different at the 1% level of significance. b) ∑ ̅ weeks, ̅ Hypotheses: Level of significance: weeks days against days ̅ Test statistic: √ √ Critical region: Reject is | | Therefore, reject the null hypothesis, and conclude that the lifetimes of the ants are significantly different at the 1% level of significance. 7. a) Significance level: 5% Rejection region: ̅ Test statistic: √ √ Do not reject , the evidence is not sufficient to accept that the analyst’s portfolio provides superior returns b) No, companies are from the same sector and subsequently, their earnings will share many common market forces. 8. Let be the mass (in grams) of a bag of potato chips. We are given that ( ) a) b) c) ( ) and ̅ ( ) ( ( ). ) then the 95% confidence interval is √ which is equivalent to ( ). d) We have 95% confidence in our method that the true population mean will be contained in the specified interval. e) That the mean filling amount is not 100g since ( ). f) Pick a bigger level of significance, e.g. for we’d have a 90% confidence interval or increase the number of observations. 2...
View Full Document

This document was uploaded on 03/19/2014.

Ask a homework question - tutors are online