College Statistics Quiz
20 questions · no time limit
0:00
DATA, VARIABLES & STUDY DESIGN
Question 1 of 20
No time limit
Current
Answered
Flagged
Not seen
A teacher wants to determine if a new educational app improves student performance. In her class of 30 students, she tells them about the app and makes it available for them to use. At the end of the unit, she compares the test scores of the 10 students who used the app most frequently with the 10 students who used it least. Why is the teacher's conclusion that the app improved scores for the high-use group likely to be flawed?
YOUR PROGRESS
20
QUESTIONS
Ready when you are
Answer in any order. Your progress shows here as you go.
QUESTIONS
KEYBOARD
Pick an answer ABCD
Next question ↵→
Previous ←
Flag for review F
Answers save as you go · flagged questions come back at the end