Unit F - Two - sample Hypothesis TestF. I - confidence Interval for Difference Between Two- sample Means

n ,= 100

I,= 450

S,= 20

Nz = 150

① ② I,= 410

Sz = 45

Step : check the assumptions

n ,= 100 330

Nz = 1507, 30 } ⇒ Z - CI is ok

6,= 62

T ←pop. Std of total

pop . standard den . points for traditionalof the total points students

for students in SWYS group

step : 959. CI ⇒ 2=0.05-

( I - E) ± ✓s÷ts÷ -

- 450-4101 I 1.96/2%+7%2I ¥ 40 I 8.2 = ( 31.8 , 48 . 2)

£0.025 = l.96

The 958 CI for the difference in the average total points forthese 2 methods is ( 31.8. 48.2) .