7. theories: rusbults investment model

what is the model

commitment depends on three factors

1. satisfaction 

2. comparison with alternatives 

3. investment 

because the investment model is a development of SET, two factors are similar to SET 

satisfaction

satisfaction = extent to which romantic partners feel the rewards of a relationship exceed the costs 

• based on the CL 

• a satisfying relationship is judged by comparing rewards and costs is seen to be profitable if it has many rewards and few costs 

comparison with alternatives

• alternatives include other partners or being single

investment

investment = resources associated with a romantic relationship which partners would lose if their relationships were to end

there are two types

1. intrinsic

2. extrinsic

intrinsic

• resources put directly into the relationship 

tangible - money, possessions 

intangible - energy, emotion and self disclosures 

extrinsic 

• resources that previously did not feature in the relationship but are now closely associated

tangible - possessions bought together ie a car, mutual friends and children

intangible - shared memories

combination of factors

if partners experience high levels of satisfaction (due to more rewards and few costs) and the alternatives are less attractive and the sizes of their investment are increasing you can confidently predict partners will be committed to the relationship

satisfaction versus commitment

rusbalt et al argued commitment is the main psychological factor that causes people to stay in romantic relationships, with satisfaction a contributory factor 

relationship maintenance mechanisms

• accommodation - dont engage in tit for tat retaliation

• willingness to sacrifice - put partners interests first 

• forgiveness - forgive for serious transgressions 

• positive illusions - unrealistically positive about their partner 

• ridicule alternatives - negative about alternatives and others relationships

evaluation

1. explains abusive relationships

2. research support (& counterpoint)

3. oversimplifies

explains abusive relationships

• model helps explain why people stay in abusive relationships

• rusbult found women in abusive relationships were more likely to stay if they had high investment and few alternatives - shows even when satisfaction is low, high investment and lack of alternatives can maintain commitment

• shows model has real world application in understanding maladaptive behaviours

research support

• supported by strong empirical evidence

• meta analysis by le et al reviewed 52 studies with 11,000 participants and found satisfaction, investment and comparison with alternatives were all linked to relationship commitment and longevity

• as meta analysis, findings are more reliable and shows model applies across different relationship types (hetero/homosexual)

• increases scientific credibility and validity of the model as a robust explanation of relationship commitment

counterpoint

• correlational data

• studies show correlations between investment and commitment but do not manipulate variables experimentally - cannot establish causation

• weakens explanatory power of the model as cannot conclusively explain why commitment develops

oversimplifies

• model may oversimplify what “investment” means

• argues model does not fully consider future-orientated investments such as shared plans so focusing mainly on past investments ignores how future goals influence commitment

• suggests model lacks depth reducing ability to fully explain relationship commitment