Rusbults model

• An extension of SET

  • Investment model developed SET and suggests that commitment depends on satisfaction level , CLalt + investment size
• Commitment to a relationship depends on :

  • Satisfaction level = extent of rewards outweighing costs
  • Comparison level with alternatives = judgement if different relationship would increase satisfaction levels
  • Investment size = resources associated with a romantic relationship
  • Formula : commitment = satisfaction - alternatives + investment
  • Commitment strengthened by Satisfaction + Investment
  • Commitment is weakened by Presence of alternatives
• Two types of investment :

  • Intrinsic : resources put directly in relationship E.g: money ,SD
  • Extrinsic : resources outside relationship that become strongly connected e.g memories , friends
• Relationship maintenance mechanisms

  Used to keep relationship going :

  1. Accomodation = promoting relationship
  2. Willingness to sacrifice = putting partners interest 1st
  3. Forgiveness
  4. Positive illusions = be unrealistically pos abt partner
  5. Derogation of alts = partner may be neg abt tempting alts
• Strength of Rusbults model : P: explains why ppl stay in abusive relationships 


  • E: Rusbult found that women who reported making the greatest investment + has the fewest attractive alternatives were more likely to return to abusive partner
  • E: Model can be applied to a wide range of relationships
  • L: SET + Equity Theory fail to explain
• Strength of rusbults model : research support

  • Satisfaction, comparison with alternatives + investment greatly contributed to commitment.
  • E: Results true for men + women in either hetero/ homosexual relationships
  • Increases the reliability + validity of the model - factors are universally important
• Limitation of Rusbults model : P: oversimplifies investment 


  • E: Goodfriend argue theres more to investment than resources already put in , e.g plans for the future
  • E: partners will be committed to staying in relationships as they want to see these plans become a reality
  • L: Investment in romantic relationships is a complex phenomenon as consists of many different factors =model reductionist