Mediation, Moderation, & Third-Variables (Content Activity #4)

Indicate whether each statement below is describing a mediation hypothesis, a third-variable argument, or a moderator result. First, state the key bivariate relationship, then identify the moderator, mediator, or third variable.

Remember:

• Moderation tells us about the strength of a relationship or under what conditions (e.g., for who, when) a relationship between X and Y can be found.
• Mediation tells us why a relationship between two variables exists. Mediation features temporal precedence, i.e., X is related to Y by way of a mediator, M, which must appear in the middle.
• A third-variable is a confound. In these relationships, variables X and Y may seem to be related on their own, but another variable really explains the connection between them.

1. Playing violent videogames is associated with aggressive behavior because temperamentally aggressive children enjoy more violent videogames.

1. Playing violent videogames is associated with aggressive behavior very strongly among teenagers, but less strongly among young adults.

1. Having a cognitively demanding job is associated with cognitive benefits in later years because people who are highly educated take cognitively demanding jobs.

1. Having a cognitively demanding job is associated with cognitive benefits in later years, but only for certain occupations, not all occupations.

1. Having a cognitively demanding job is associated with cognitive benefits in later years because cognitive challenge builds lasting connections in the brain.