Rusbult's Investment Model (AQA A Level Psychology): Revision Note

The key features of Rusbult's Investment Model

• Rusbult et al. (2011) argue that commitment in a relationship depends on three factors:

  • Satisfaction

  • Comparison with alternatives

  • Investment size

• The first two factors are drawn from Social Exchange Theory (SET)

  • Satisfaction is based on the concept of the comparison level (CL): a satisfying relationship is one where rewards exceed costs, judged against previous relationship experience and social norms

  • Comparison level for alternatives (CLalt) involves a partner asking whether their needs would be better met outside the current relationship

    • Alternatives include not just other relationships but having no relationship at all

• Investment size is the third, crucial factor added by the model

  • When satisfaction is high, alternatives are less attractive, and investment size is increasing, commitment to the relationship will follow

• RIM (like Social Exchange Theory and Equity Theory) is an economic theory of relationships, but  it attempts to refine and expand on some aspects of SET

Investment in relationships

• Investment refers to how much each person has brought to the relationship: quality as well as quantity

  • Investment size refers to the overall value of that investment

• As all financial advisors will tell potential investors, investments can lose value as well as increase over time, and this is particularly true of relationships

  • If the relationship ends, both partners are likely to lose out financially, emotionally, and materially

• There are two types of investment according to the model:

  • Intrinsic investment – this comprises everything that each individual has brought separately to the relationship, e.g.

    • money

    • possessions

    • time

    • energy

    • episodes of self-disclosure

  • Extrinsic investment – this comprises resources that previously did not feature in the relationship but are now closely associated with it, e.g.

    • children

    • possessions bought together

    • mutual friends acquired since the relationship began

    • shared memories

• If both partners have substantially invested in the relationship (by investing materially and/or emotionally), then the relationship is likely to survive, even if satisfaction is low at times (this has some relevance to the cognitive bias of the sunk-cost fallacy)

• RIM explains why some relationships can persist even when satisfaction levels are low and alternatives exist

  • Rusbult argues that this is due to commitment being more important overall than satisfaction in a relationship

Commitment in relationships

• Commitment describes the extent to which a couple is resolved to remain together and endure the challenges and hardships that arise in their relationship

• Rusbult et al. (2011) argue that the main psychological factor causing people to stay in a relationship is not satisfaction but commitment

  • This explains why dissatisfied partners may choose to stay: they are committed because they have made an investment they do not want to see go to waste, so they will work hard to maintain and repair a damaged relationship

• According to Rusbult, commitment helps to maintain a relationship; e.g., a couple will attempt to work through a ‘rough patch’ to repair the relationship as both of them have committed (even though this may, at times, be unpleasant or involve hard work)

• Strategies that RIM suggests to maintain commitment include:

  • Sacrifice on both sides – this means that each partner is willing to put their other half first rather than pursuing selfish motivations

  • Positive illusions created – this involves an unrealistic idealisation of each other, alongside 'ridiculing alternatives' - being negative about tempting alternatives and viewing other people's relationships as inferior to their own

  • Accommodation – this involves not engaging in petty point-scoring: the couple will do what they can to protect the relationship from harm

  • Forgiveness – even when this may be difficult, e.g., if one of the partners has an affair, for example

Research which investigates Rusbult’s Investment Model

• Le & Agnew (2003) – a meta-analysis of 52 studies (late 1970s–1999) comprising around 11,000 participants from five countries concluded that satisfaction, CLalt and investment size all predicted commitment; relationships with the greatest commitment were the most stable and longest-lasting

  • These findings were true for men and women, across cultures, and for homosexual as well as heterosexual couples, suggesting the model has some universal validity

• Impett et al. (2002) – a longitudinal study of 3,627 married couples, which found a significant positive correlation between satisfaction and commitment, with investment size also predicting commitment

• Rusbult & Martz (1995) – interviews with women living in a shelter for survivors of domestic abuse revealed that those who reported making the greatest investment in the relationship and having the fewest attractive alternatives were most likely to return to their abusive partner

  • This supports the model's claim that satisfaction alone does not determine whether someone stays; a victim of abuse does not have to be satisfied with the relationship to remain in it

Evaluation of Rusbult’s Investment Model

Strengths

• Research in this field, such as Le & Agnew (2003), used a large sample and quantitative data, which means that the findings are robust and able to withstand statistical analysis, which in turn increases their reliability

• Recognising that commitment is a key factor linked to investment size explains why someone would stay in an abusive relationship

• Much of the supporting research uses self-report methods, but this is appropriate for this model

  • It is the partner's perception of investment, satisfaction and alternatives that influences commitment, not the objective reality of these factors

Limitations

• It is difficult to separate the key components of RIM; e.g., intrinsic and extrinsic investments may overlap or be difficult to distinguish from each other

• The theory could be used to perpetuate abusive relationships by the abuser, i.e., knowing that the abused partner is committed to the relationship and has few alternatives could grant power to the abusive partner

• Much of the supporting research is correlational; strong correlations exist between satisfaction, CLalt, investment and commitment, but this does not show that these factors cause commitment

  • It could be that greater commitment leads to greater investment, the reverse of what the model predicts

Issues & Debates

• RIM has been used to explain why people remain in abusive relationships, such as in Rusbult & Martz (1995)

  • While this has real-world application, it is also socially sensitive, as it could be misused to justify or normalise staying in harmful situations, especially when commitment is based on high investment and lack of alternatives

  • Psychologists must consider the ethical implications of applying RIM in such contexts