Investment model

• Rusbult (2011) suggested that commitment and investment are both more important than satisfaction in determining the likelihood of a successful relationship. There are three factors which determine the level of commitment within a relationship:

  1. Satisfaction levels.
  2. Comparison with alternatives.
  3. Investment size.

  He argues that satisfaction occurs when each partner sees large profits and that there are fewer plausible or profitable alternatives, in which they can invest their resources.
• Categories of investment:

  1. Intrinsic - Resources put directly into the relationship. This includes money, time and efforts.
  2. Extrinsic - Resources that have come about as a result of the relationship. This includes a shared mortgage, memories and children.
• The size of the investment dictates how hard each partner will work to salvage their relationship, and thus demonstrate commitment. From an economic viewpoint, this commitment is almost selfish in that it is carried out purely not to lose the investment.
• Rusbult suggested that there are mechanisms which facilitate commitment:

  1. Ridiculing alternatives - Minimising the advantages of potential alternatives and viewing them in a negative light.
  2. Positive illusions - Being unrealistically positive about partner's qualities.
  3. Forgiveness - Willingness to forgive minor and major mistakes.
  4. Willingness to sacrifice - Putting partner's interests first.
  5. Accommodation - acting in a way that promotes relationships, rather than keeping a tally of costs and rewards.
• Strengths of the investment model:

  • High ecological validity - It can easily explain abusive relationships by shifting the focus from relationship satisfaction to that of investment and viable alternatives. Rusbult found that the predictions based off of the model can explain why ‘battered women’ often return to their abusive partners, and explained this in terms of making significant investments and having few alternative partners, rather than satisfaction. This shift of focus may be considered refreshing and a more valid explanation of abusive relationships compared to SET or equity theory.
• Strengths of the investment model:

  • Although self-report measures are usually criticised as lacking objectivity and creating qualitative data, this is not the case here. The key elements of his model focus on an individual’s perception of their investments, as opposed to a quantitative value. This has high ecological validity when considering that an individual’s own perception is often different to their partners in the instance of relationship breakdown. Therefore, Rusbult’s investment model has used the correct methodology to accurately reflect the subjective nature of the model’s features.
• Limitations of the investment model:

  • The Investment Model sees the motivation to continue with a relationship according to the investments, time and energy which an individual has contributed. BUT, the motivation to see a couple’s future plans may be a bigger predictor of relationship success, as opposed to initial investments which are often very low in the early stages of romantic relationships. This was suggested by Goodfriend and Agnew. Therefore, Rusbult’s model may have oversimplified the concept of investment and its future implications on the plans that couples make together.
• Limitations of the investment model:

  • Based on correlational research - Research studies show strong correlations between factors, but it does not follow that these factors cause commitment (e.g. perhaps commitment comes before investment). Therefore it is not clear that the model has identified the causes of commitment, rather the factors that are associated with it.