A(n) _______________ threat is any factor that leads to ...

[viki]

A(n) _______________ threat is any factor that leads to differences between the groups at the start of the study.
 
  Fill in the blank(s) with correct word

Question 2

Which of the following is a disadvantage of using a within subjects design?
 
  a. the variability due to participants cannot be estimated statistically
  b. treatment order may have an effect on the dependent variable
  c. a large number of participants is required
  d. the experimental and control groups may not be equivalent to one another

[raili21]

Answer to Question 1

selection

Answer to Question 2

B

[viki]

Excellent

[nguyenhoanhat]

Gracias!