Ex post facto research is less convincing than experimental ...

[fahad]

Ex post facto research is less convincing than experimental research because
 
  a. there is no control over the dependent variables.
  b. differences in the independent variable were present before the start of the study.
  c. differences in the dependent variable were present before the start of the study.
  d. the independent variable preceded the dependent variable in time.
  e. b and c

Question 2

The internal validity threat that randomization eliminates in an experimental study is
 
  a. selection bias. c. instrumentation.
  b. subject effects. d. history.

[matt]

Answer to Question 1

B

Answer to Question 2

A

[fahad]

Excellent

[AmberC1996]

Gracias!