{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

409Quiz3Eans - Decision The value of the test statistic is...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
STAT 409 Fall 2011 Version E Name ANSWERS . Quiz 3 (10 points) Be sure to show all your work; your partial credit might depend on it. No credit will be given without supporting work. 1. Last season, a baseball player’s performance was as follows: Day Games Night Games At bat, n i ( “attempts” ) 240 160 Base hits, Y i ( “successes” ) 72 56 a) (5) Test H 0 : p Day = 0.34 vs. H 1 : p Day < 0.34 at a 10% level of significance. Y = 72. n = 240. 240 72 Y ˆ = = n p = 0.30. Test Statistic: Z = ( ) 240 66 . 0 34 . 0 34 . 0 30 . 0 1 0 0 0 ˆ - = - - n p p p p = 1.31 . P-value: Left – tailed. P-value = P( Z 1.31 ) = 0.0951 . Decision: P-value < α = 0.10. Reject H 0 at α = 0.10. OR Rejection Region: Reject H 0 if Z < – z α z 0.10 = – 1.282.
Background image of page 1

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

View Full Document Right Arrow Icon
Background image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Decision: The value of the test statistic is in the Rejection Region. Reject H at α = 0.10. b) (5) The player claims that he hits better during night games than during day games. Find the p-value of the test H : p Day = p Night vs. H 1 : p Day < p Night . 240 72 Y 1 1 1 ˆ = = n p = 0.30. 160 56 Y 2 2 2 ˆ = = n p = 0.35. 32 . ˆ 400 128 160 240 56 72 Y Y 2 1 2 1 = = + + = + + = n n p . Test Statistic: Z = +-⋅ ⋅ 160 1 240 1 68 . 32 . 35 . 30 . = – 1.05 . P-value: Left – tailed. P-value = ( area of the left tail ) = P( Z ≤ – 1.05 ) = 0.1469 ....
View Full Document

{[ snackBarMessage ]}

Page1 / 2

409Quiz3Eans - Decision The value of the test statistic is...

This preview shows document pages 1 - 2. Sign up to view the full document.

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