Rusbult's Investment Model

• Investment Model


  Developed by Rusbult as a development of SET and its limitations. Suggests that commitment depends on three factors:

  • Satisfaction level
  • Comparison with alternatives
  • Investment size
• Factor 1 : Satisfaction


  Based on the concept of comparison level, where a satisfying relationship is judged by comparing rewards and costs, and is profitable if rewards outweigh costs. Each partner is satisfied if they are getting more from the relationship than they expected.
• Factor 2 : Comparison with alternatives


  A partner identifies whether their needs could be better met outside of the relationship, even if the alternative is no relationship.
• Factor 3 : Investment Size


  = the extent and importance of resources associated with the relationship

  • Intrinsic - any resource we put directly into the relationship, can be tangible (furniture) or intangible (energy)
  • Extrinsic - resources that are now associated with the relationship, can be tangible (possessions bought together, children) or intangible (shared memories)
• When satisfaction is high, alternatives are less attractive and the investment size is large, we can predict partners will be committed to the relationship .
• Satisfaction vs Commitment


  Rusbult argued the main psychological factor for people staying in relationships is commitment, with satisfaction as a contributor. This explains why dissatisfied partners may choose to stay in a relationship, because they are committed.

  They've made an investment they do not want to go to wast and so will work hard to maintain and repair a damaged relationship.
• Relationship Maintenance Mechanisms


  Commitment expresses itself in everyday behaviours:

  • Accommodation - acting to promote the relationship
  • Willingness to sacrifice
  • Forgiveness

  Cognitive:

  • Positive illusions - about partner
  • Ridiculing alternatives- negative about alternatives and other people's relationships
• Eval : Strength


  Le and Agnew did a meta-analysis of 52 studies with 11,000 participants from 5 countries and found that satisfaction, comparison with alternatives and investment size all predicated relationship commitment. Adds validity to the model.
• Eval : Strength


  Rusbult and Martz studied women in abuse shelters and found those most likely to return to their abusive partners reported making the greatest investment and having fewer alternatives. Suggests an explanation for why victims stay in abusive relationships and can help to support them.
• Eval : Weakness


  Goodfriend and Agnew say there is more to investment than just resources, as in the early stages there will be little investments. They extend the model to include the investment partners make in their future plans, and commit to each other to see the plans work out. Suggests the original model is a limited explanation and too simplistic.