PAL PSYU3349 Week 4

Which of the following best describes 1) Independent variables of interest and 2) Covariates

• 1) Any IV in the model

  2) Any IV not included in the model

• 1) An IV whose relationship with the DV we are mainly interested in

  2) IVs we want to control for

• 1) An IV we want to control for

  2) An IV whose relationship with the DV we are mainly interested in

• 1) An IV (only categorical) whose relationship with the DV we are mainly interested in

  2) IVs (only numeric) in the model we want to control for

Match the definitions to the correct terms:

1) An interaction

2) A causal association (only from longitudinal data)

3) The association between an IV and DV is partly attributable to another variable

• 1) Moderation

  2) Mediation

  3) Confounding

• 1) Moderation

  2) Mediation

  3) Confounding

• 1) Mediation

  2) Moderation

  2) Confounding

• 1) Mediation

  2) Confounding

  2) Moderation

What do the following scatterplots reveal?

• Confounding

• Mediation

• Suppression

What do the following scatterplots reveal?

• Confounding

• Mediation

• Suppression

If X describes a numeric/continuous IV and Z describes dummy variables for a categorical IV (with 3 levels), which of the following would be the prediction equation for an Interaction Model?

•  $E\left[Y\right]\ =\alpha+βX+β_1Z_1+β_2Z_2+β_3XZ_1+β_4XZ_2$ 

• $E\left[Y\right]=α+βX+β_1Z_1+β_2Z_2+β_3Z_3$

• $E\left[Y\right]=\alpha+\beta_1+\beta_2+\beta_3$

• 
   $E[Y]=α+β_1XZ_1+β_2XZ_2$ 
  

What does adding "c." in front of an IV in STATA do?

• Tells STATA to create dummy variables

• Tells STATA to centre the IV

• Tells STATA to treat the IV as a continuous/numeric variable

• Tells STATA to treat the IV as a covariate in the model