08 STAT HWA a - Dr. Valerie R. Bencivenga Economics 329...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Dr. Valerie R. Bencivenga Economics 329 PRACTICE ASSIGNMENT #8A: RIGHT ANSWERS 1.a. i X = days of absenteeism of employee i Obs n ,..., 1 i , X i are iid   2 , N with 2 2 5   1 , 0 N ~ n X because the population is normal 1 n z X n z X C u u 96 . 1 Z of quantile 975 . z 05 . 10 n 5 3 . 6 X u 2 2 95 . 10 5 96 . 1 3 . 6 10 5 96 . 1 3 . 6 C (full credit answer)   95 . 4 . 9 2 . 3 C b. 1 n z X n z X C u u      9604 n 98 96 . 1 2 2 . 5 n 2 . n 5 96 . 1 2 2 . n z 2 Length u 2.a. i X = interest rate charged on loan i Obs n ,..., 1 i , X i are iid   2 , N 1 n t ~ n s X because the population is normal (and the population variance is unknown) 1 n t X n t X C u u ) t using ( 75 . 2 t of quantile 995 . t 01 . 36 n 21 s 85 X 30 35 u (Use the table value for the closest degrees of freedom to 35, here either 30 or 40) 99 . 36 21 75 . 2 85 36 21 75 . 2 85 C (full credit answer)   99 . 625 . 94 375 . 75 C b.   2 1 n 2 2 ~ s 1 n because the population is normal 1 s ) 1 n ( s ) 1 n ( C 2 l 2 2 2 u 2 with 01 . ) using ( 67 . 53 of quantile 995 . and 79 . 13 of quantile 005 . 2 30 2 35 2 u 2 35 2 l (Use table values for closest degrees of freedom to 35, here either 30 or 40.) 99 . 79 . 13 21 ) 35 ( 67 . 53 21 ) 35 ( C 2 2 2 (full credit answer)   99 . 3 . 1119 6 . 287 C 2
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
3.a. i X = fees applied to account i n ,..., 1 i , X i are iid ) , ( N 2 1 n t ~ n s X because the population is normal (and the population variance is unknown) 05 . , 60 s , 7 . 197 X , 34 n 2 2 1 n s t X n s t X C u u Here u t = 97.5 th percentile of 33 t . Use the 97.5 th percentile of 30 t = 2.042, the closest table value 95 . 34 60 042 . 2 7 . 197 34 60 042 . 2 7 . 197 C (full credit answer)   95 . 71 . 218 69 . 176 C b. 2 1 n 2 2 ~ s ) 1 n ( because the population is normal 05 . , 60 s , 34 n 2 2 1 s ) 1 n ( s ) 1 n ( C 2 l 2 2 2 u 2 Here 2 l = 2.5 th percentile of 2 33 , and 2 u = 97.5 th percentile of 2 33 . Use the 2.5 th and 97.5 th percentiles of
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 02/26/2012 for the course ECONOMICS 329 taught by Professor Bencivenga during the Spring '12 term at University of Texas at Austin.

Page1 / 6

08 STAT HWA a - Dr. Valerie R. Bencivenga Economics 329...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online