For three weeks Mr. Gomez recorded the amount of homework his fourth grade students turned in. The ...

For three weeks Mr. Gomez recorded the amount of homework his fourth grade students turned in. The next three weeks he rewarded those who turned in homework with free playtime and recorded the turn-in rate for these three weeks. Mr. Gomez is using which design?
 
  a. Counterbalanced c. 3 1 3 factorial
  b. One-group time series d. Multiple single-subject design

Ques. 2

Indicate whether the following statements are true or false. Validity is a unitary concept, but with different types of evidence of score validity.
 
  a. true b. false

Ques. 3

The main disadvantage of a counterbalanced design is the lack of control for
 
  a. carry-over effect of treatment. c. preexisting differences.
  b. internal validity. d. pretest sensitization.