In a study of SAT scores, a researcher believes that students will score signifi
ID: 3219554 • Letter: I
Question
In a study of SAT scores, a researcher believes that students will
score significantly higher on their second attempt at the exam.
To test this claim, 9 students were randomly selected.
Their scores on the first and second attempts at the SAT exam are shown below:
Student | A B C D E F G H I
---------------------------------------------------------------------------------------
First SAT score | 480 510 530 540 550 560 600 620 660
Second SAT score | 490 520 550 530 580 580 610 640 690
What is the test statistic for this test?
.552
.0027
3.78
.294
.552
.0027
3.78
.294
Explanation / Answer
The statistical software output for this problem is:
Paired T hypothesis test:
D = 1 - 2 : Mean of the difference between Second SAT Score and First SAT Score
H0 : D = 0
HA : D > 0
Hypothesis test results:
Hence,
Test statistic = 3.78 [T-Stat in the table]
Option C is correct.
Difference Mean Std. Err. DF T-Stat P-value Second SAT Score - First SAT Score 15.555556 4.1201103 8 3.7755192 0.0027